Midi interface

Archiver

Howdy stampers.

I'm wondering if anyone has built a stamp interface to a MIDI device. I
messed with MIDI programming back in the 80's, so I'm somewhat familiar
with the protocol, but I've never actually built an inteface. I found a
schematic that seems to be a very simple op-amp circuit tagged "TTL to
midi". Has anyone done something like this with a stamp?

Thanks!

Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
email: lamont@a... WWW: http://www.serv.net
"...There's no moral, it's just a lot of stuff that happens". - H. Simpson

Archiver

Hi,

I'm also interested in this. Concerning MIDI Out, you just need two
resistors....
This web page should answer your question:
http://www.interaccess.org/arg/arg-knowledge/MIDI.BS2

Concerning MIDI IN, you need more circuitry but unfortunately, it's not really
possible with the stamp because there are no interrupts to warn you that new
MIDI data has arrived, and the serial port is unbuffered, so you will loose
information. Even by adding a buffer, I'm not sure it's possible because the
Stamp is too slow...

Tell me if you find something interesting for the MIDI IN....

Nicolas




>>> "Sean T. Lamont .lost." <lamont@a...> 12/10/00 02:34PM >>>

Howdy stampers.

I'm wondering if anyone has built a stamp interface to a MIDI device. I
messed with MIDI programming back in the 80's, so I'm somewhat familiar
with the protocol, but I've never actually built an inteface. I found a
schematic that seems to be a very simple op-amp circuit tagged "TTL to
midi". Has anyone done something like this with a stamp?

Thanks!

Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
email: lamont@a... WWW: http://www.serv.net
"...There's no moral, it's just a lot of stuff that happens". - H. Simpson

Archiver

On Mon, 11 Dec 2000, Nicolas Fournel wrote:

> I'm also interested in this. Concerning MIDI Out, you just need two
resistors....
> This web page should answer your question:
> http://www.interaccess.org/arg/arg-knowledge/MIDI.BS2

I found a spec at http://www.art.net/~troika/schematic.html ;

This seems peculiar because they invert the output (why not just use the
inverted bits?) and use a NPN transistor, but I have no idea why. The
stamp2 should be able to natively do 31.25 kilobaud.

> Concerning MIDI IN, you need more circuitry but unfortunately, it's not
>really possible with the stamp because there are no interrupts to warn
>you that new MIDI data has arrived, and the serial port is unbuffered, so
>you will loose information. Even by adding a buffer, I'm not sure it's
>possible because the Stamp is too slow...

I don't really need it, but it seems to me that the stamp could pull 31
baud data. Especially since a large amount of midi is very low-bandwidth
(note on and off). The only thing which consumes lots of bandwidth is
wheel modulation and timing information. You'd basically have to have a
dedicated stamp to midi in, though.


> Tell me if you find something interesting for the MIDI IN....


Check out that schematic...

Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
email: lamont@a... WWW: http://www.serv.net
"...There's no moral, it's just a lot of stuff that happens". - H. Simpson

Archiver

By the way, it's in the midi spec that the devices are optoisolated from
each other, which is why the schematic at art.net has an optotriac (I
think that's what that is...)

On Mon, 11 Dec 2000, Nicolas Fournel wrote:

> Hi,
>
> I'm also interested in this. Concerning MIDI Out, you just need two
resistors....
> This web page should answer your question:
> http://www.interaccess.org/arg/arg-knowledge/MIDI.BS2
>
> Concerning MIDI IN, you need more circuitry but unfortunately, it's not really
possible with the stamp because there are no interrupts to warn you that new
MIDI data has arrived, and the serial port is unbuffered, so you will loose
information. Even by adding a buffer, I'm not sure it's possible because the
Stamp is too slow...
>
> Tell me if you find something interesting for the MIDI IN....
>
> Nicolas
>
>
>
>
> >>> "Sean T. Lamont .lost." <lamont@a...> 12/10/00 02:34PM >>>
>
> Howdy stampers.
>
> I'm wondering if anyone has built a stamp interface to a MIDI device. I
> messed with MIDI programming back in the 80's, so I'm somewhat familiar
> with the protocol, but I've never actually built an inteface. I found a
> schematic that seems to be a very simple op-amp circuit tagged "TTL to
> midi". Has anyone done something like this with a stamp?
>
> Thanks!
>
> Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
> Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
> email: lamont@a... WWW: http://www.serv.net
> "...There's no moral, it's just a lot of stuff that happens". - H. Simpson
>
>
>
>
>
>

Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
email: lamont@a... WWW: http://www.serv.net
"...There's no moral, it's just a lot of stuff that happens". - H. Simpson

Archiver

Hi,

Yes, this is part of the MIDI spec.
I found the web site below very interesting:

http://devices.sapp.org/program/stamp/


It explains pretty well the speed and buffering problems and you can see a few
nice sample programs.

Nicolas



>>> "Sean T. Lamont .lost." <lamont@a...> 12/11/00 07:42PM >>>

By the way, it's in the midi spec that the devices are optoisolated from
each other, which is why the schematic at art.net has an optotriac (I
think that's what that is...)

On Mon, 11 Dec 2000, Nicolas Fournel wrote:

> Hi,
>
> I'm also interested in this. Concerning MIDI Out, you just need two
resistors....
> This web page should answer your question:
> http://www.interaccess.org/arg/arg-knowledge/MIDI.BS2
>
> Concerning MIDI IN, you need more circuitry but unfortunately, it's not really
possible with the stamp because there are no interrupts to warn you that new
MIDI data has arrived, and the serial port is unbuffered, so you will loose
information. Even by adding a buffer, I'm not sure it's possible because the
Stamp is too slow...
>
> Tell me if you find something interesting for the MIDI IN....
>
> Nicolas
>
>
>
>
> >>> "Sean T. Lamont .lost." <lamont@a...> 12/10/00 02:34PM >>>
>
> Howdy stampers.
>
> I'm wondering if anyone has built a stamp interface to a MIDI device. I
> messed with MIDI programming back in the 80's, so I'm somewhat familiar
> with the protocol, but I've never actually built an inteface. I found a
> schematic that seems to be a very simple op-amp circuit tagged "TTL to
> midi". Has anyone done something like this with a stamp?
>
> Thanks!
>
> Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
> Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
> email: lamont@a... WWW: http://www.serv.net
> "...There's no moral, it's just a lot of stuff that happens". - H. Simpson
>
>
>
>
>
>

Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
email: lamont@a... WWW: http://www.serv.net
"...There's no moral, it's just a lot of stuff that happens". - H. Simpson

Archiver

I actually did it without the optoisolation - I know why it's spec'd to be
optoisolated, it's because musicians end up cabling them together,
potentially with large voltage amounts flowing down it. For a stamp, it
just doesn't matter. As per another schematic , I did it with two 220 ohm
resistors at 31.25 kilobaud, and it worked just fine. I had my stamp
acting as a little drum machine. [noparse]:)[/noparse]



On Tue, 12 Dec 2000, Nicolas Fournel wrote:

> Hi,
>
> Yes, this is part of the MIDI spec.
> I found the web site below very interesting:
>
> http://devices.sapp.org/program/stamp/
>
>
> It explains pretty well the speed and buffering problems and you can see a few
nice sample programs.
>
> Nicolas
>
>
>
> >>> "Sean T. Lamont .lost." <lamont@a...> 12/11/00 07:42PM >>>
>
> By the way, it's in the midi spec that the devices are optoisolated from
> each other, which is why the schematic at art.net has an optotriac (I
> think that's what that is...)
>
> On Mon, 11 Dec 2000, Nicolas Fournel wrote:
>
> > Hi,
> >
> > I'm also interested in this. Concerning MIDI Out, you just need two
resistors....
> > This web page should answer your question:
> > http://www.interaccess.org/arg/arg-knowledge/MIDI.BS2
> >
> > Concerning MIDI IN, you need more circuitry but unfortunately, it's not
really possible with the stamp because there are no interrupts to warn you that
new MIDI data has arrived, and the serial port is unbuffered, so you will loose
information. Even by adding a buffer, I'm not sure it's possible because the
Stamp is too slow...
> >
> > Tell me if you find something interesting for the MIDI IN....
> >
> > Nicolas
> >
> >
> >
> >
> > >>> "Sean T. Lamont .lost." <lamont@a...> 12/10/00 02:34PM >>>
> >
> > Howdy stampers.
> >
> > I'm wondering if anyone has built a stamp interface to a MIDI device. I
> > messed with MIDI programming back in the 80's, so I'm somewhat familiar
> > with the protocol, but I've never actually built an inteface. I found a
> > schematic that seems to be a very simple op-amp circuit tagged "TTL to
> > midi". Has anyone done something like this with a stamp?
> >
> > Thanks!
> >
> > Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
> > Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
> > email: lamont@a... WWW: http://www.serv.net
> > "...There's no moral, it's just a lot of stuff that happens". - H. Simpson
> >
> >
> >
> >
> >
> >
>
> Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
> Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
> email: lamont@a... WWW: http://www.serv.net
> "...There's no moral, it's just a lot of stuff that happens". - H. Simpson
>
>
>
>
>
>

Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
email: lamont@a... WWW: http://www.serv.net
"...There's no moral, it's just a lot of stuff that happens". - H. Simpson

Archiver

Hello all,
I've recently acquired the pedal board to an old electric organ that
I would like to MIDIfy. I've found a few resources online
(http://www.audiomulch.com/midipic/ mainly) that lead me to believe
this could be done with a BASIC Stamp. I haven't worked with these
before, but I've done some programming and learn relatively fast. I
think this project seems like a good first with the Stamps.

The page I mentioned earlier (http://www.audiomulch.com/midipic/)
talks mainly about creating a MIDI control-signal sending device. I
want to be able to hook up about 26 switches or contacts from the
pedals and send MIDI note on/off info. I might be able to modify the
source code (http://www.interaccess.org/arg/arg-knowledge/MIDI.BS2)
that was provided to work with the switches/contacts I speak of
rather than analog inputs (potentometers, etc) which it currently
does. I could likely work the software end if I could have a little
help hooking up the switches. I know the BASIC Stamp II only has 16
pins, but could I hook up more inputs? There are 26 pedals, and I
would like to utilize them all, if possible. The Stamp II seems the
Stamp most in my working price range, but if it doesn't fit the bill,
I would consider something with more capabilities.

I guess I'm just a little fuzzy about how inputs and such interface
with the pins on the controller and then the software. If anyone has
any advice or expertise they can offer, I would appreciate it. If
anyone has attempted a MIDI pedalboard/keyboard type controller,
their wisdom would be immensely helpful.

Thanks!
~Sam

P.S. I think if this works, I might try to salvage the rest of this
organ... I guess it works fine except some idiotic kids bashed up all
the keys. I was thinking maybe a MIDI-in device so I could run the
thing from an external MIDI keyboard. Maybe something else is in line
there, though.

Archiver

Yes, you can do MIDI with the BASIC Stamp. Here's a couple N&V
resources that should help:

http://www.parallax.com/dl/docs/cols/nv/vol4/col/94.pdf
http://www.parallax.com/dl/docs/cols/nv/vol4/col/95.pdf

-- Jon Williams
-- Parallax

---

Original Message

---

From: captaink1234 [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=mmfkGp5yWP9bUOBKgf_X9i26kVjwgUMJpOkck6ZSzMXJ3qPiHjn8pOU419XAW7chw3fpy4vGt8nNMGGes4Y]captaink1234@y...[/url
Sent: Thursday, March 04, 2004 11:10 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] MIDI Interface


Hello all,
I've recently acquired the pedal board to an old electric organ that
I would like to MIDIfy. I've found a few resources online
(http://www.audiomulch.com/midipic/ mainly) that lead me to believe
this could be done with a BASIC Stamp. I haven't worked with these
before, but I've done some programming and learn relatively fast. I
think this project seems like a good first with the Stamps.

The page I mentioned earlier (http://www.audiomulch.com/midipic/)
talks mainly about creating a MIDI control-signal sending device. I
want to be able to hook up about 26 switches or contacts from the
pedals and send MIDI note on/off info. I might be able to modify the
source code (http://www.interaccess.org/arg/arg-knowledge/MIDI.BS2)
that was provided to work with the switches/contacts I speak of
rather than analog inputs (potentometers, etc) which it currently
does. I could likely work the software end if I could have a little
help hooking up the switches. I know the BASIC Stamp II only has 16
pins, but could I hook up more inputs? There are 26 pedals, and I
would like to utilize them all, if possible. The Stamp II seems the
Stamp most in my working price range, but if it doesn't fit the bill,
I would consider something with more capabilities.

I guess I'm just a little fuzzy about how inputs and such interface
with the pins on the controller and then the software. If anyone has
any advice or expertise they can offer, I would appreciate it. If
anyone has attempted a MIDI pedalboard/keyboard type controller,
their wisdom would be immensely helpful.

Thanks!
~Sam

P.S. I think if this works, I might try to salvage the rest of this
organ... I guess it works fine except some idiotic kids bashed up all
the keys. I was thinking maybe a MIDI-in device so I could run the
thing from an external MIDI keyboard. Maybe something else is in line
there, though.

Archiver

MIDI needs something like 31.8k baud, I don't think you'll get there
with these devices. 9600 is tops for a BS2, it looks like the BS2SX
might do double that. You'll need to go to micro controller that
doesn't do the language interpretation, that usually means learning
assembly or something more difficult than P Basic.



--- captaink1234 <captaink1234@y...> wrote:
> Hello all,
> I've recently acquired the pedal board to an old electric organ that
> I would like to MIDIfy. I've found a few resources online
> (http://www.audiomulch.com/midipic/ mainly) that lead me to believe
> this could be done with a BASIC Stamp. I haven't worked with these
> before, but I've done some programming and learn relatively fast. I
> think this project seems like a good first with the Stamps.
>
> The page I mentioned earlier (http://www.audiomulch.com/midipic/)
> talks mainly about creating a MIDI control-signal sending device. I
> want to be able to hook up about 26 switches or contacts from the
> pedals and send MIDI note on/off info. I might be able to modify the
> source code (http://www.interaccess.org/arg/arg-knowledge/MIDI.BS2)
> that was provided to work with the switches/contacts I speak of
> rather than analog inputs (potentometers, etc) which it currently
> does. I could likely work the software end if I could have a little
> help hooking up the switches. I know the BASIC Stamp II only has 16
> pins, but could I hook up more inputs? There are 26 pedals, and I
> would like to utilize them all, if possible. The Stamp II seems the
> Stamp most in my working price range, but if it doesn't fit the bill,
>
> I would consider something with more capabilities.
>
> I guess I'm just a little fuzzy about how inputs and such interface
> with the pins on the controller and then the software. If anyone has
> any advice or expertise they can offer, I would appreciate it. If
> anyone has attempted a MIDI pedalboard/keyboard type controller,
> their wisdom would be immensely helpful.
>
> Thanks!
> ~Sam
>
> P.S. I think if this works, I might try to salvage the rest of this
> organ... I guess it works fine except some idiotic kids bashed up all
>
> the keys. I was thinking maybe a MIDI-in device so I could run the
> thing from an external MIDI keyboard. Maybe something else is in line
>
> there, though.
>
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject
> and Body of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>


__________________________________
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Yahoo! Search - Find what you’re looking for faster
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Archiver

I want to completely disagree with this.

Please reference the following url:

http://www.zenchemical.com/burningman/lightwave/

This was a project I put together that was at number of art events ; the
most recently was a little over year ago at the string cheese incident
show in san franscisco. The fundamental basis for it is converting
optical / electrical signals into midi. The conversion boxes are
completely based on BS2.

What I would recommend for the original poster is that he figure out some
way of multiplexing the inputs. (shift registers or something) The midi
output should be very straightforward. For your reference, instead of
using 31.25 kbaud, which is the spec, I had to use "32768" baud on the
BS2. I'm not precisely sure why, but there it is.

On Fri, 5 Mar 2004, John Remington wrote:

> MIDI needs something like 31.8k baud, I don't think you'll get there
> with these devices. 9600 is tops for a BS2, it looks like the BS2SX
> might do double that. You'll need to go to micro controller that
> doesn't do the language interpretation, that usually means learning
> assembly or something more difficult than P Basic.
>
>
>
> --- captaink1234 <captaink1234@y...> wrote:
> > Hello all,
> > I've recently acquired the pedal board to an old electric organ that
> > I would like to MIDIfy. I've found a few resources online
> > (http://www.audiomulch.com/midipic/ mainly) that lead me to believe
> > this could be done with a BASIC Stamp. I haven't worked with these
> > before, but I've done some programming and learn relatively fast. I
> > think this project seems like a good first with the Stamps.
> >
> > The page I mentioned earlier (http://www.audiomulch.com/midipic/)
> > talks mainly about creating a MIDI control-signal sending device. I
> > want to be able to hook up about 26 switches or contacts from the
> > pedals and send MIDI note on/off info. I might be able to modify the
> > source code (http://www.interaccess.org/arg/arg-knowledge/MIDI.BS2)
> > that was provided to work with the switches/contacts I speak of
> > rather than analog inputs (potentometers, etc) which it currently
> > does. I could likely work the software end if I could have a little
> > help hooking up the switches. I know the BASIC Stamp II only has 16
> > pins, but could I hook up more inputs? There are 26 pedals, and I
> > would like to utilize them all, if possible. The Stamp II seems the
> > Stamp most in my working price range, but if it doesn't fit the bill,
> >
> > I would consider something with more capabilities.
> >
> > I guess I'm just a little fuzzy about how inputs and such interface
> > with the pins on the controller and then the software. If anyone has
> > any advice or expertise they can offer, I would appreciate it. If
> > anyone has attempted a MIDI pedalboard/keyboard type controller,
> > their wisdom would be immensely helpful.
> >
> > Thanks!
> > ~Sam
> >
> > P.S. I think if this works, I might try to salvage the rest of this
> > organ... I guess it works fine except some idiotic kids bashed up all
> >
> > the keys. I was thinking maybe a MIDI-in device so I could run the
> > thing from an external MIDI keyboard. Maybe something else is in line
> >
> > there, though.
> >
> >
> >
> >
> > To UNSUBSCRIBE, just send mail to:
> > basicstamps-unsubscribe@yahoogroups.com
> > from the same email address that you subscribed. Text in the Subject
> > and Body of the message will be ignored.
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
>
>
> __________________________________
> Do you Yahoo!?
> Yahoo! Search - Find what you’re looking for faster
> http://search.yahoo.com
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and Body
of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>
>

Sean T. Lamont, Chief Mad Scientist |-- lamont@a...
Zen Chemical Productions |-- http://www.zenchemical.com
Fabricators of Unnecessary Amazement

Archiver

Where in the world did you get that 9600 baud is tops for a BS2?
Perhaps one of our competitors.... When in doubt, consult the Help
file. We put it there so you'd have the facts at your fingertips.

The BS2 can handle MIDI with no trouble at all; BASIC Stamps are used by
artists and musicians quite frequently.

-- Jon Williams
-- Applications Engineer, Parallax
-- Dallas Office

---

Original Message

---

From: John Remington [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=IflTtZzVr0mfO8UH9W6d3iXi8xt6ztCw-Ujp1remJutFlAq_7AAszNX1TvWWlOW8n5Hx7kCohw]jrem123@y...[/url
Sent: Friday, March 05, 2004 1:45 PM
To: basicstamps@yahoogroups.com
Subject: Re: [noparse][[/noparse]basicstamps] MIDI Interface


MIDI needs something like 31.8k baud, I don't think you'll get there
with these devices. 9600 is tops for a BS2, it looks like the BS2SX
might do double that. You'll need to go to micro controller that
doesn't do the language interpretation, that usually means learning
assembly or something more difficult than P Basic.

Archiver

I would also argue that the 'language' interpretation is irrelevant in
this case. When you're sending data bits out, you're not interpreting any
more, you're (presumably) in a tightly-coded assembler routine to do
serial output, and it would very much surprise me if this were any slower
on a stamp than on an equivalent PIC or assembler-based microcontroller.

On Fri, 5 Mar 2004, John Remington wrote:

> MIDI needs something like 31.8k baud, I don't think you'll get there
> with these devices. 9600 is tops for a BS2, it looks like the BS2SX
> might do double that. You'll need to go to micro controller that
> doesn't do the language interpretation, that usually means learning
> assembly or something more difficult than P Basic.
>
>
>

Sean T. Lamont, Chief Mad Scientist |-- lamont@a...
Zen Chemical Productions |-- http://www.zenchemical.com
Fabricators of Unnecessary Amazement

Archiver

I perceived that info from page 297 of the 2.0 ref manual (the serout
baud rate table), not from one of your competitors. I guess I don't
understand what "open baud networking" means. But I'm willing to
listen and learn . . .



--- Jon Williams <jwilliams@p...> wrote:
> Where in the world did you get that 9600 baud is tops for a BS2?
> Perhaps one of our competitors.... When in doubt, consult the Help
> file. We put it there so you'd have the facts at your fingertips.
>
> The BS2 can handle MIDI with no trouble at all; BASIC Stamps are used
> by
> artists and musicians quite frequently.
>
> -- Jon Williams
> -- Applications Engineer, Parallax
> -- Dallas Office
>
>
>

---

Original Message

---

> From: John Remington [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=UCIBG7-aDa820o7rsbjkIEl8u8pMrVaDTYf7lE8P7jqGwM_tUk33LMjM-SNTkktdfMGo5Vy-h8Zr]jrem123@y...[/url
> Sent: Friday, March 05, 2004 1:45 PM
> To: basicstamps@yahoogroups.com
> Subject: Re: [noparse][[/noparse]basicstamps] MIDI Interface
>
>
> MIDI needs something like 31.8k baud, I don't think you'll get there
> with these devices. 9600 is tops for a BS2, it looks like the BS2SX
> might do double that. You'll need to go to micro controller that
> doesn't do the language interpretation, that usually means learning
> assembly or something more difficult than P Basic.
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject
> and Body of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>


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Do you Yahoo!?
Yahoo! Search - Find what you’re looking for faster
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Archiver

then why is the minimum delay in serout 1ms?

--- "Sean T. Lamont .lost." <lamont@a...> wrote:
>
> I would also argue that the 'language' interpretation is irrelevant
> in
> this case. When you're sending data bits out, you're not interpreting
> any
> more, you're (presumably) in a tightly-coded assembler routine to do
> serial output, and it would very much surprise me if this were any
> slower
> on a stamp than on an equivalent PIC or assembler-based
> microcontroller.
>
> On Fri, 5 Mar 2004, John Remington wrote:
>
> > MIDI needs something like 31.8k baud, I don't think you'll get
> there
> > with these devices. 9600 is tops for a BS2, it looks like the
> BS2SX
> > might do double that. You'll need to go to micro controller that
> > doesn't do the language interpretation, that usually means learning
> > assembly or something more difficult than P Basic.
> >
> >
> >
>
> Sean T. Lamont, Chief Mad Scientist |--
> lamont@a...
> Zen Chemical Productions |--
> http://www.zenchemical.com
> Fabricators of Unnecessary Amazement
>
>
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject
> and Body of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>


__________________________________
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Yahoo! Search - Find what you’re looking for faster
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Archiver

You'll notice that the label on the chart is "common baud rates" -- the
key being common. Turn back a few pages to the quick facts table and
you'll see that the BS2 has a baud range of 243 baud to 50 kBaud.

-- Jon Williams
-- Applications Engineer, Parallax
-- Dallas Office

---

Original Message

---

From: John Remington [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=G_G570moz1G4mf36A8Za_zfD2LbgUMwPS69y024VHnHtP70d3-IdyqzF2B4oPOrcUDS8TnBfmWR0]jrem123@y...[/url
Sent: Friday, March 05, 2004 7:14 PM
To: basicstamps@yahoogroups.com
Subject: RE: [noparse][[/noparse]basicstamps] MIDI Interface


I perceived that info from page 297 of the 2.0 ref manual (the serout
baud rate table), not from one of your competitors. I guess I don't
understand what "open baud networking" means. But I'm willing to listen
and learn . . .



--- Jon Williams <jwilliams@p...> wrote:
> Where in the world did you get that 9600 baud is tops for a BS2?
> Perhaps one of our competitors.... When in doubt, consult the Help
> file. We put it there so you'd have the facts at your fingertips.
>
> The BS2 can handle MIDI with no trouble at all; BASIC Stamps are used
> by artists and musicians quite frequently.
>
> -- Jon Williams
> -- Applications Engineer, Parallax
> -- Dallas Office
>
>
>

---

Original Message

---

> From: John Remington [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=G_G570moz1G4mf36A8Za_zfD2LbgUMwPS69y024VHnHtP70d3-IdyqzF2B4oPOrcUDS8TnBfmWR0]jrem123@y...[/url
> Sent: Friday, March 05, 2004 1:45 PM
> To: basicstamps@yahoogroups.com
> Subject: Re: [noparse][[/noparse]basicstamps] MIDI Interface
>
>
> MIDI needs something like 31.8k baud, I don't think you'll get there
> with these devices. 9600 is tops for a BS2, it looks like the BS2SX
> might do double that. You'll need to go to micro controller that
> doesn't do the language interpretation, that usually means learning
> assembly or something more difficult than P Basic.
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject
> and Body of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>


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Yahoo! Search - Find what you're looking for faster
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To UNSUBSCRIBE, just send mail to:
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This message has been scanned by WebShield. Please report SPAM to
abuse@p....

Archiver

The only delay involved in the routines is the fetch and setup time from
EEPROM; on the order to 150 microseconds, depending on the Stamp version
and instruction (for those that are interested, Dr. Tracy Allen has done
a study on instruction execution speeds).

Sean was right, however, once SEROUT (or any other PBASIC instruction)
is loaded and running, assembly code is what is doing the work. This is
why instructions like PULSOUT and PULSIN can have a resolution of 2
microseconds -- that would not be possible without assembly code speed.

-- Jon Williams
-- Applications Engineer, Parallax
-- Dallas Office

---

Original Message

---

From: John Remington [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=ImCBsClj2Vi2Od6fR0gN4w2ZQoJ78V7Xni2QN-zTdTW95-33JLUYqCAthiVwty5ZIkyr8sscawRddpY]jrem123@y...[/url
Sent: Friday, March 05, 2004 7:17 PM
To: basicstamps@yahoogroups.com
Subject: Re: [noparse][[/noparse]basicstamps] MIDI Interface


then why is the minimum delay in serout 1ms?

--- "Sean T. Lamont .lost." <lamont@a...> wrote:
>
> I would also argue that the 'language' interpretation is irrelevant in
> this case. When you're sending data bits out, you're not interpreting
> any
> more, you're (presumably) in a tightly-coded assembler routine to do
> serial output, and it would very much surprise me if this were any
> slower
> on a stamp than on an equivalent PIC or assembler-based
> microcontroller.
>
> On Fri, 5 Mar 2004, John Remington wrote:
>
> > MIDI needs something like 31.8k baud, I don't think you'll get
> there
> > with these devices. 9600 is tops for a BS2, it looks like the
> BS2SX
> > might do double that. You'll need to go to micro controller that
> > doesn't do the language interpretation, that usually means learning
> > assembly or something more difficult than P Basic.
> >
> >
> >
>
> Sean T. Lamont, Chief Mad Scientist |--
> lamont@a...
> Zen Chemical Productions |--
> http://www.zenchemical.com
> Fabricators of Unnecessary Amazement

Archiver

The open baud modes will only drive the serial line in one direction and
require a pull-up/pull-down to move the line in the other direction (the
BASIC Stamp pin floats at this point to allow the pull-up/pull-down to
do its job). This is very useful when you want to connect a bunch of
devices to the same serial line.

If, for example, you use an open, non-inverted baud mode. This would
require a pull-up on the serial line since the BASIC Stamp (and other
compliant devices) will pull the line low for state 0, let the line
float (under control of the pull-up) for state 1. Even if two devices
try to talk at the same time they will not be conflicting with each
other since they can only pull the line low.

But, if you were using a driven baud where the Stamp and other devices
drive both directions, the possibility exists that one device could
drive the serial line high while the other drives it low -- this would
create a conflict [noparse][[/noparse]direct short] and damage a device.

-- Jon Williams
-- Applications Engineer, Parallax
-- Dallas Office

---

Original Message

---

From: John Remington [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=uh4MJxkqzDgQbhMUFIjlAeMcCzxYHvYjJqzhC3PxPyhIEISRaU5EY0QktRiVRPh_90V5W76UyC7zDA]jrem123@y...[/url
Sent: Friday, March 05, 2004 7:14 PM
To: basicstamps@yahoogroups.com
Subject: RE: [noparse][[/noparse]basicstamps] MIDI Interface


I perceived that info from page 297 of the 2.0 ref manual (the serout
baud rate table), not from one of your competitors. I guess I don't
understand what "open baud networking" means. But I'm willing to listen
and learn . . .



--- Jon Williams <jwilliams@p...> wrote:
> Where in the world did you get that 9600 baud is tops for a BS2?
> Perhaps one of our competitors.... When in doubt, consult the Help
> file. We put it there so you'd have the facts at your fingertips.
>
> The BS2 can handle MIDI with no trouble at all; BASIC Stamps are used
> by artists and musicians quite frequently.
>
> -- Jon Williams
> -- Applications Engineer, Parallax
> -- Dallas Office
>
>
>

---

Original Message

---

> From: John Remington [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=uh4MJxkqzDgQbhMUFIjlAeMcCzxYHvYjJqzhC3PxPyhIEISRaU5EY0QktRiVRPh_90V5W76UyC7zDA]jrem123@y...[/url
> Sent: Friday, March 05, 2004 1:45 PM
> To: basicstamps@yahoogroups.com
> Subject: Re: [noparse][[/noparse]basicstamps] MIDI Interface
>
>
> MIDI needs something like 31.8k baud, I don't think you'll get there
> with these devices. 9600 is tops for a BS2, it looks like the BS2SX
> might do double that. You'll need to go to micro controller that
> doesn't do the language interpretation, that usually means learning
> assembly or something more difficult than P Basic.

Archiver

Fair enough, I learn something every day.

--- Jon Williams <jwilliams@p...> wrote:
> The open baud modes will only drive the serial line in one direction
> and
> require a pull-up/pull-down to move the line in the other direction
> (the
> BASIC Stamp pin floats at this point to allow the pull-up/pull-down
> to
> do its job). This is very useful when you want to connect a bunch of
> devices to the same serial line.
>
> If, for example, you use an open, non-inverted baud mode. This would
> require a pull-up on the serial line since the BASIC Stamp (and other
> compliant devices) will pull the line low for state 0, let the line
> float (under control of the pull-up) for state 1. Even if two
> devices
> try to talk at the same time they will not be conflicting with each
> other since they can only pull the line low.
>
> But, if you were using a driven baud where the Stamp and other
> devices
> drive both directions, the possibility exists that one device could
> drive the serial line high while the other drives it low -- this
> would
> create a conflict [noparse][[/noparse]direct short] and damage a device.
>
> -- Jon Williams
> -- Applications Engineer, Parallax
> -- Dallas Office
>
>
>

---

Original Message

---

> From: John Remington [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=sFZzXAgygPCzAcyRx2JtX01N52oMELXa8w_3D5hkGbDafaQieR0ol7QkNllzOOMfjpMhY-qhhGCnww]jrem123@y...[/url
> Sent: Friday, March 05, 2004 7:14 PM
> To: basicstamps@yahoogroups.com
> Subject: RE: [noparse][[/noparse]basicstamps] MIDI Interface
>
>
> I perceived that info from page 297 of the 2.0 ref manual (the serout
> baud rate table), not from one of your competitors. I guess I don't
> understand what "open baud networking" means. But I'm willing to
> listen
> and learn . . .
>
>
>
> --- Jon Williams <jwilliams@p...> wrote:
> > Where in the world did you get that 9600 baud is tops for a BS2?
> > Perhaps one of our competitors.... When in doubt, consult the Help
>
> > file. We put it there so you'd have the facts at your fingertips.
> >
> > The BS2 can handle MIDI with no trouble at all; BASIC Stamps are
> used
> > by artists and musicians quite frequently.
> >
> > -- Jon Williams
> > -- Applications Engineer, Parallax
> > -- Dallas Office
> >
> >
> >

---

Original Message

---

> > From: John Remington [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=sFZzXAgygPCzAcyRx2JtX01N52oMELXa8w_3D5hkGbDafaQieR0ol7QkNllzOOMfjpMhY-qhhGCnww]jrem123@y...[/url
> > Sent: Friday, March 05, 2004 1:45 PM
> > To: basicstamps@yahoogroups.com
> > Subject: Re: [noparse][[/noparse]basicstamps] MIDI Interface
> >
> >
> > MIDI needs something like 31.8k baud, I don't think you'll get
> there
> > with these devices. 9600 is tops for a BS2, it looks like the
> BS2SX
> > might do double that. You'll need to go to micro controller that
> > doesn't do the language interpretation, that usually means learning
>
> > assembly or something more difficult than P Basic.
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject
> and Body of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>


__________________________________
Do you Yahoo!?
Yahoo! Search - Find what you’re looking for faster
http://search.yahoo.com

Archiver

'Open' baud modes give you what used to be
called a 'wired-or' buss. This gives a
multi-master communication line. As long as
only one 'talker' is talking at a time,
multiple 'listeners' can listen on the line
and get the data.

You CAN have multiple talkers without damage,
but the data will be garbled if two talk at
the same time. Your protocol will have to
provide some way around this -- typically,
a sync byte at the start, and a checksum
at the end.

--- In basicstamps@yahoogroups.com, "Jon Williams" <jwilliams@p...>
wrote:
> The open baud modes will only drive the serial line in one
direction and
> require a pull-up/pull-down to move the line in the other direction
(the
> BASIC Stamp pin floats at this point to allow the pull-up/pull-down
to
> do its job). This is very useful when you want to connect a bunch
of
> devices to the same serial line.
>
> If, for example, you use an open, non-inverted baud mode. This
would
> require a pull-up on the serial line since the BASIC Stamp (and
other
> compliant devices) will pull the line low for state 0, let the line
> float (under control of the pull-up) for state 1. Even if two
devices
> try to talk at the same time they will not be conflicting with each
> other since they can only pull the line low.
>
> But, if you were using a driven baud where the Stamp and other
devices
> drive both directions, the possibility exists that one device could
> drive the serial line high while the other drives it low -- this
would
> create a conflict [noparse][[/noparse]direct short] and damage a device.
>
> -- Jon Williams
> -- Applications Engineer, Parallax
> -- Dallas Office
>
>
>

---

Original Message

---

> From: John Remington [noparse][[/noparse]mailto:jrem123@y...]
> Sent: Friday, March 05, 2004 7:14 PM
> To: basicstamps@yahoogroups.com
> Subject: RE: [noparse][[/noparse]basicstamps] MIDI Interface
>
>
> I perceived that info from page 297 of the 2.0 ref manual (the
serout
> baud rate table), not from one of your competitors. I guess I don't
> understand what "open baud networking" means. But I'm willing to
listen
> and learn . . .
>
>
>
> --- Jon Williams <jwilliams@p...> wrote:
> > Where in the world did you get that 9600 baud is tops for a BS2?
> > Perhaps one of our competitors.... When in doubt, consult the
Help
> > file. We put it there so you'd have the facts at your fingertips.
> >
> > The BS2 can handle MIDI with no trouble at all; BASIC Stamps are
used
> > by artists and musicians quite frequently.
> >
> > -- Jon Williams
> > -- Applications Engineer, Parallax
> > -- Dallas Office
> >
> >
> >

---

Original Message

---

> > From: John Remington [noparse][[/noparse]mailto:jrem123@y...]
> > Sent: Friday, March 05, 2004 1:45 PM
> > To: basicstamps@yahoogroups.com
> > Subject: Re: [noparse][[/noparse]basicstamps] MIDI Interface
> >
> >
> > MIDI needs something like 31.8k baud, I don't think you'll get
there
> > with these devices. 9600 is tops for a BS2, it looks like the
BS2SX
> > might do double that. You'll need to go to micro controller that
> > doesn't do the language interpretation, that usually means
learning
> > assembly or something more difficult than P Basic.

Archiver

"What I would recommend for the original poster is that he figure out some
way of multiplexing the inputs. (shift registers or something)"

I think that's what I'm looking for... The 26 pedals/keys cannot be
connected completely individually, correct? So, by "shift registers",
do you mean to have each key trigger one of twelve inputs for the
correct note name and then simultaneously switch the correct octave to
play? This wouldn't do very well with polyphony, but I think it could
work. Of course, if you meant something entirely different, share
that, too :-)

Now, before I buy one of these seemingly wonderful microcontrollers, I
want to understand how it would work in conjunction with what I'm
looking to do. I'm looking at the BS2 which has 24 pins. To have a
"switch" type event, would I simply connect one wire to one pin, and
another to a ground pin, and upon contact of the two wires the program
could read it? How many of these switcherthingies could I have on one
BS2? Would I need any fancy resistors or anything between the switches
and pins?

Right now, the only experience I have with these Stamps is very
limited contact with the BS2sx in an IFI Robotics Isaac 16 Robot
Controller (http://www.ifirobotics.com) and that seems to read all the
neat little inputs it has set up for me with great ease. I became
interested in the Stamps upon realizing what was inside so many of
these killing machines that we trusted our very lives to.

Well, thanks again,
~Sam Kronick


--- In basicstamps@yahoogroups.com, "Sean T. Lamont .lost."
<lamont@a...> wrote:
>
> I want to completely disagree with this.
>
> Please reference the following url:
>
> http://www.zenchemical.com/burningman/lightwave/
>
> This was a project I put together that was at number of art events ; the
> most recently was a little over year ago at the string cheese incident
> show in san franscisco. The fundamental basis for it is converting
> optical / electrical signals into midi. The conversion boxes are
> completely based on BS2.
>
> What I would recommend for the original poster is that he figure out
some
> way of multiplexing the inputs. (shift registers or something) The midi
> output should be very straightforward. For your reference, instead of
> using 31.25 kbaud, which is the spec, I had to use "32768" baud on the
> BS2. I'm not precisely sure why, but there it is.
>
> On Fri, 5 Mar 2004, John Remington wrote:
>
> > MIDI needs something like 31.8k baud, I don't think you'll get there
> > with these devices. 9600 is tops for a BS2, it looks like the BS2SX
> > might do double that. You'll need to go to micro controller that
> > doesn't do the language interpretation, that usually means learning
> > assembly or something more difficult than P Basic.
> >
> >
> >
> > --- captaink1234 <captaink1234@y...> wrote:
> > > Hello all,
> > > I've recently acquired the pedal board to an old electric organ that
> > > I would like to MIDIfy. I've found a few resources online
> > > (http://www.audiomulch.com/midipic/ mainly) that lead me to believe
> > > this could be done with a BASIC Stamp. I haven't worked with these
> > > before, but I've done some programming and learn relatively fast. I
> > > think this project seems like a good first with the Stamps.
> > >
> > > The page I mentioned earlier (http://www.audiomulch.com/midipic/)
> > > talks mainly about creating a MIDI control-signal sending device. I
> > > want to be able to hook up about 26 switches or contacts from the
> > > pedals and send MIDI note on/off info. I might be able to modify the
> > > source code (http://www.interaccess.org/arg/arg-knowledge/MIDI.BS2)
> > > that was provided to work with the switches/contacts I speak of
> > > rather than analog inputs (potentometers, etc) which it currently
> > > does. I could likely work the software end if I could have a little
> > > help hooking up the switches. I know the BASIC Stamp II only has 16
> > > pins, but could I hook up more inputs? There are 26 pedals, and I
> > > would like to utilize them all, if possible. The Stamp II seems the
> > > Stamp most in my working price range, but if it doesn't fit the
bill,
> > >
> > > I would consider something with more capabilities.
> > >
> > > I guess I'm just a little fuzzy about how inputs and such interface
> > > with the pins on the controller and then the software. If anyone has
> > > any advice or expertise they can offer, I would appreciate it. If
> > > anyone has attempted a MIDI pedalboard/keyboard type controller,
> > > their wisdom would be immensely helpful.
> > >
> > > Thanks!
> > > ~Sam
> > >
> > > P.S. I think if this works, I might try to salvage the rest of this
> > > organ... I guess it works fine except some idiotic kids bashed
up all
> > >
> > > the keys. I was thinking maybe a MIDI-in device so I could run the
> > > thing from an external MIDI keyboard. Maybe something else is in
line
> > >
> > > there, though.
> > >
> > >
> > >
> > >
> > > To UNSUBSCRIBE, just send mail to:
> > > basicstamps-unsubscribe@yahoogroups.com
> > > from the same email address that you subscribed. Text in the
Subject
> > > and Body of the message will be ignored.
> > >
> > > Yahoo! Groups Links
> > >
> > >
> > >
> > >
> > >
> >
> >
> > __________________________________
> > Do you Yahoo!?
> > Yahoo! Search - Find what you're looking for faster
> > http://search.yahoo.com
> >
> >
> > To UNSUBSCRIBE, just send mail to:
> > basicstamps-unsubscribe@yahoogroups.com
> > from the same email address that you subscribed. Text in the
Subject and Body of the message will be ignored.
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
>
> Sean T. Lamont, Chief Mad Scientist |-- lamont@a...
> Zen Chemical Productions |--
http://www.zenchemical.com
> Fabricators of Unnecessary Amazement

Archiver

There are many ways to multiplex I/O. I haven't worked extensively with
shift registers, but basically they allow input and output states to
transmit using TTL pulses over a single I/O line. You could also use octal
latches, which allow you to view switches a bank of 8 at a time (I used a
BS2 and 8 octal latches to multiplex 64 I/O lines off of the 16 I/O
pins...)

Another thing that might be pretty useful to consider is looking at a PS2
driver and hacking a standard keyboard for the 110 switches. You're
unlikely to be able to get velocity or poly-pressure data for any of these
things.

I'm sort of curious why you want to recreate a cheap MIDI keyboard,
though. MIDI is much more interesting to play with, I find, when you're
building devices that are uncommon.


On Tue, 9 Mar 2004, captaink1234 wrote:

> "What I would recommend for the original poster is that he figure out some
> way of multiplexing the inputs. (shift registers or something)"
>
> I think that's what I'm looking for... The 26 pedals/keys cannot be
> connected completely individually, correct? So, by "shift registers",
> do you mean to have each key trigger one of twelve inputs for the
> correct note name and then simultaneously switch the correct octave to
> play? This wouldn't do very well with polyphony, but I think it could
> work. Of course, if you meant something entirely different, share
> that, too :-)
>
> Now, before I buy one of these seemingly wonderful microcontrollers, I
> want to understand how it would work in conjunction with what I'm
> looking to do. I'm looking at the BS2 which has 24 pins. To have a
> "switch" type event, would I simply connect one wire to one pin, and
> another to a ground pin, and upon contact of the two wires the program
> could read it? How many of these switcherthingies could I have on one
> BS2? Would I need any fancy resistors or anything between the switches
> and pins?
>
> Right now, the only experience I have with these Stamps is very
> limited contact with the BS2sx in an IFI Robotics Isaac 16 Robot
> Controller (http://www.ifirobotics.com) and that seems to read all the
> neat little inputs it has set up for me with great ease. I became
> interested in the Stamps upon realizing what was inside so many of
> these killing machines that we trusted our very lives to.
>
> Well, thanks again,
> ~Sam Kronick
>
>
> --- In basicstamps@yahoogroups.com, "Sean T. Lamont .lost."
> <lamont@a...> wrote:
> >
> > I want to completely disagree with this.
> >
> > Please reference the following url:
> >
> > http://www.zenchemical.com/burningman/lightwave/
> >
> > This was a project I put together that was at number of art events ; the
> > most recently was a little over year ago at the string cheese incident
> > show in san franscisco. The fundamental basis for it is converting
> > optical / electrical signals into midi. The conversion boxes are
> > completely based on BS2.
> >
> > What I would recommend for the original poster is that he figure out
> some
> > way of multiplexing the inputs. (shift registers or something) The midi
> > output should be very straightforward. For your reference, instead of
> > using 31.25 kbaud, which is the spec, I had to use "32768" baud on the
> > BS2. I'm not precisely sure why, but there it is.
> >
> > On Fri, 5 Mar 2004, John Remington wrote:
> >
> > > MIDI needs something like 31.8k baud, I don't think you'll get there
> > > with these devices. 9600 is tops for a BS2, it looks like the BS2SX
> > > might do double that. You'll need to go to micro controller that
> > > doesn't do the language interpretation, that usually means learning
> > > assembly or something more difficult than P Basic.
> > >
> > >
> > >
> > > --- captaink1234 <captaink1234@y...> wrote:
> > > > Hello all,
> > > > I've recently acquired the pedal board to an old electric organ that
> > > > I would like to MIDIfy. I've found a few resources online
> > > > (http://www.audiomulch.com/midipic/ mainly) that lead me to believe
> > > > this could be done with a BASIC Stamp. I haven't worked with these
> > > > before, but I've done some programming and learn relatively fast. I
> > > > think this project seems like a good first with the Stamps.
> > > >
> > > > The page I mentioned earlier (http://www.audiomulch.com/midipic/)
> > > > talks mainly about creating a MIDI control-signal sending device. I
> > > > want to be able to hook up about 26 switches or contacts from the
> > > > pedals and send MIDI note on/off info. I might be able to modify the
> > > > source code (http://www.interaccess.org/arg/arg-knowledge/MIDI.BS2)
> > > > that was provided to work with the switches/contacts I speak of
> > > > rather than analog inputs (potentometers, etc) which it currently
> > > > does. I could likely work the software end if I could have a little
> > > > help hooking up the switches. I know the BASIC Stamp II only has 16
> > > > pins, but could I hook up more inputs? There are 26 pedals, and I
> > > > would like to utilize them all, if possible. The Stamp II seems the
> > > > Stamp most in my working price range, but if it doesn't fit the
> bill,
> > > >
> > > > I would consider something with more capabilities.
> > > >
> > > > I guess I'm just a little fuzzy about how inputs and such interface
> > > > with the pins on the controller and then the software. If anyone has
> > > > any advice or expertise they can offer, I would appreciate it. If
> > > > anyone has attempted a MIDI pedalboard/keyboard type controller,
> > > > their wisdom would be immensely helpful.
> > > >
> > > > Thanks!
> > > > ~Sam
> > > >
> > > > P.S. I think if this works, I might try to salvage the rest of this
> > > > organ... I guess it works fine except some idiotic kids bashed
> up all
> > > >
> > > > the keys. I was thinking maybe a MIDI-in device so I could run the
> > > > thing from an external MIDI keyboard. Maybe something else is in
> line
> > > >
> > > > there, though.
> > > >
> > > >
> > > >
> > > >
> > > > To UNSUBSCRIBE, just send mail to:
> > > > basicstamps-unsubscribe@yahoogroups.com
> > > > from the same email address that you subscribed. Text in the
> Subject
> > > > and Body of the message will be ignored.
> > > >
> > > > Yahoo! Groups Links
> > > >
> > > >
> > > >
> > > >
> > > >
> > >
> > >
> > > __________________________________
> > > Do you Yahoo!?
> > > Yahoo! Search - Find what you're looking for faster
> > > http://search.yahoo.com
> > >
> > >
> > > To UNSUBSCRIBE, just send mail to:
> > > basicstamps-unsubscribe@yahoogroups.com
> > > from the same email address that you subscribed. Text in the
> Subject and Body of the message will be ignored.
> > >
> > > Yahoo! Groups Links
> > >
> > >
> > >
> > >
> > >
> > >
> >
> > Sean T. Lamont, Chief Mad Scientist |-- lamont@a...
> > Zen Chemical Productions |--
> http://www.zenchemical.com
> > Fabricators of Unnecessary Amazement
>
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and Body
of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>
>

Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
email: lamont@a... WWW: http://www.serv.net
"Do not fear mistakes, There Are None" - Miles Davis

Archiver

If you look back at the original thread, I'm not looking to build a
MIDI keyboard exactly, but a controller based on the pedal board of an
electric organ. I know it's similar, and judging by your projects on
your website, the "uncommon" devices you speak of are laser harps and
such, but I think I'll start somewhere simple. I just think it would
be neat to have some bass tones that I could play and jam along with
while playing guitar or the like. There are MIDI pedals out there, but
I believe they are quite out of my spending range, and to DIY is
always more fun :-)

Based on the application I'm looking at, polyphony would be nice,
velocity sensitivity completely unneccessary. Monophony would be
entirely acceptable if I could reliably play the pedals without
accidentally hitting one on either side of the tone I wished to play.
I'm sure I could program it to not play just the last pedal pressed,
but the last pedal pressed that is still being held down. Due to the
potential complexity of such a system and the number of times it would
need be duplicated, TTL pulses and such seems out of the question. I
would need a device/circuit that would create the right pulse for each
of the pedals, correct? In that case, I think octal latches might be
the best way to go. Judging from your math, I could hook up 8
independent switches at a time on the 16 IO pins. Does that mean there
is no way to have a common ground? If I wanted to represent all 12
tones, I would have to think in "registers" more than octaves, for a
third of an octave would actually be one register higher, if you
follow. I could develop a system with only 8 tones per octave (major
scale) and transpose that to the correct key, as long as all the notes
stayed in that key.

But now I'm just brainstorming in front of all of you. Maybe someone
could help me decide what kind of system to use from the above ideas.
If all this seems a little far-reaching, I can go to my backup plan of
wiring this board to one of my two allmighty Casio SK-1's. An un-bent
unit wouldn't produce tones low enough for what I want, but this is no
un-bent unit... No, my friends, this beast is your new savior.

But that is neither here nor there. Thanks a lot!
~Sam Kronick


--- In basicstamps@yahoogroups.com, "Sean T. Lamont .lost."
<lamont@a...> wrote:
>
> There are many ways to multiplex I/O. I haven't worked extensively with
> shift registers, but basically they allow input and output states to
> transmit using TTL pulses over a single I/O line. You could also use
octal
> latches, which allow you to view switches a bank of 8 at a time (I
used a
> BS2 and 8 octal latches to multiplex 64 I/O lines off of the 16 I/O
> pins...)
>
> Another thing that might be pretty useful to consider is looking at
a PS2
> driver and hacking a standard keyboard for the 110 switches. You're
> unlikely to be able to get velocity or poly-pressure data for any of
these
> things.
>
> I'm sort of curious why you want to recreate a cheap MIDI keyboard,
> though. MIDI is much more interesting to play with, I find, when you're
> building devices that are uncommon.
>
>
> On Tue, 9 Mar 2004, captaink1234 wrote:
>
> > "What I would recommend for the original poster is that he figure
out some
> > way of multiplexing the inputs. (shift registers or something)"
> >
> > I think that's what I'm looking for... The 26 pedals/keys cannot be
> > connected completely individually, correct? So, by "shift registers",
> > do you mean to have each key trigger one of twelve inputs for the
> > correct note name and then simultaneously switch the correct octave to
> > play? This wouldn't do very well with polyphony, but I think it could
> > work. Of course, if you meant something entirely different, share
> > that, too :-)
> >
> > Now, before I buy one of these seemingly wonderful microcontrollers, I
> > want to understand how it would work in conjunction with what I'm
> > looking to do. I'm looking at the BS2 which has 24 pins. To have a
> > "switch" type event, would I simply connect one wire to one pin, and
> > another to a ground pin, and upon contact of the two wires the program
> > could read it? How many of these switcherthingies could I have on one
> > BS2? Would I need any fancy resistors or anything between the switches
> > and pins?
> >
> > Right now, the only experience I have with these Stamps is very
> > limited contact with the BS2sx in an IFI Robotics Isaac 16 Robot
> > Controller (http://www.ifirobotics.com) and that seems to read all the
> > neat little inputs it has set up for me with great ease. I became
> > interested in the Stamps upon realizing what was inside so many of
> > these killing machines that we trusted our very lives to.
> >
> > Well, thanks again,
> > ~Sam Kronick
> >
> >
> > --- In basicstamps@yahoogroups.com, "Sean T. Lamont .lost."
> > <lamont@a...> wrote:
> > >
> > > I want to completely disagree with this.
> > >
> > > Please reference the following url:
> > >
> > > http://www.zenchemical.com/burningman/lightwave/
> > >
> > > This was a project I put together that was at number of art
events ; the
> > > most recently was a little over year ago at the string cheese
incident
> > > show in san franscisco. The fundamental basis for it is converting
> > > optical / electrical signals into midi. The conversion boxes are
> > > completely based on BS2.
> > >
> > > What I would recommend for the original poster is that he figure out
> > some
> > > way of multiplexing the inputs. (shift registers or something)
The midi
> > > output should be very straightforward. For your reference,
instead of
> > > using 31.25 kbaud, which is the spec, I had to use "32768" baud
on the
> > > BS2. I'm not precisely sure why, but there it is.
> > >
> > > On Fri, 5 Mar 2004, John Remington wrote:
> > >
> > > > MIDI needs something like 31.8k baud, I don't think you'll get
there
> > > > with these devices. 9600 is tops for a BS2, it looks like the
BS2SX
> > > > might do double that. You'll need to go to micro controller that
> > > > doesn't do the language interpretation, that usually means
learning
> > > > assembly or something more difficult than P Basic.
> > > >
> > > >
> > > >
> > > > --- captaink1234 <captaink1234@y...> wrote:
> > > > > Hello all,
> > > > > I've recently acquired the pedal board to an old electric
organ that
> > > > > I would like to MIDIfy. I've found a few resources online
> > > > > (http://www.audiomulch.com/midipic/ mainly) that lead me to
believe
> > > > > this could be done with a BASIC Stamp. I haven't worked with
these
> > > > > before, but I've done some programming and learn relatively
fast. I
> > > > > think this project seems like a good first with the Stamps.
> > > > >
> > > > > The page I mentioned earlier
(http://www.audiomulch.com/midipic/)
> > > > > talks mainly about creating a MIDI control-signal sending
device. I
> > > > > want to be able to hook up about 26 switches or contacts
from the
> > > > > pedals and send MIDI note on/off info. I might be able to
modify the
> > > > > source code
(http://www.interaccess.org/arg/arg-knowledge/MIDI.BS2)
> > > > > that was provided to work with the switches/contacts I speak of
> > > > > rather than analog inputs (potentometers, etc) which it
currently
> > > > > does. I could likely work the software end if I could have a
little
> > > > > help hooking up the switches. I know the BASIC Stamp II only
has 16
> > > > > pins, but could I hook up more inputs? There are 26 pedals,
and I
> > > > > would like to utilize them all, if possible. The Stamp II
seems the
> > > > > Stamp most in my working price range, but if it doesn't fit the
> > bill,
> > > > >
> > > > > I would consider something with more capabilities.
> > > > >
> > > > > I guess I'm just a little fuzzy about how inputs and such
interface
> > > > > with the pins on the controller and then the software. If
anyone has
> > > > > any advice or expertise they can offer, I would appreciate
it. If
> > > > > anyone has attempted a MIDI pedalboard/keyboard type controller,
> > > > > their wisdom would be immensely helpful.
> > > > >
> > > > > Thanks!
> > > > > ~Sam
> > > > >
> > > > > P.S. I think if this works, I might try to salvage the rest
of this
> > > > > organ... I guess it works fine except some idiotic kids bashed
> > up all
> > > > >
> > > > > the keys. I was thinking maybe a MIDI-in device so I could
run the
> > > > > thing from an external MIDI keyboard. Maybe something else is in
> > line
> > > > >
> > > > > there, though.
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > To UNSUBSCRIBE, just send mail to:
> > > > > basicstamps-unsubscribe@yahoogroups.com
> > > > > from the same email address that you subscribed. Text in the
> > Subject
> > > > > and Body of the message will be ignored.
> > > > >
> > > > > Yahoo! Groups Links
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > >
> > > >
> > > > __________________________________
> > > > Do you Yahoo!?
> > > > Yahoo! Search - Find what you're looking for faster
> > > > http://search.yahoo.com
> > > >
> > > >
> > > > To UNSUBSCRIBE, just send mail to:
> > > > basicstamps-unsubscribe@yahoogroups.com
> > > > from the same email address that you subscribed. Text in the
> > Subject and Body of the message will be ignored.
> > > >
> > > > Yahoo! Groups Links
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > >
> > > Sean T. Lamont, Chief Mad Scientist |-- lamont@a...
> > > Zen Chemical Productions |--
> > http://www.zenchemical.com
> > > Fabricators of Unnecessary Amazement
> >
> >
> >
> >
> > To UNSUBSCRIBE, just send mail to:
> > basicstamps-unsubscribe@yahoogroups.com
> > from the same email address that you subscribed. Text in the
Subject and Body of the message will be ignored.
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
>
> Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
> Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma -
Bremerton
> email: lamont@a... WWW: http://www.serv.net
> "Do not fear mistakes, There Are None" - Miles Davis

Archiver

On Fri, 12 Mar 2004, captaink1234 wrote:

>
> Based on the application I'm looking at, polyphony would be nice,
> velocity sensitivity completely unneccessary. Monophony would be
> entirely acceptable if I could reliably play the pedals without
> accidentally hitting one on either side of the tone I wished to play.
> I'm sure I could program it to not play just the last pedal pressed,
> but the last pedal pressed that is still being held down. Due to the
> potential complexity of such a system and the number of times it would
> need be duplicated, TTL pulses and such seems out of the question. I
> would need a device/circuit that would create the right pulse for each
> of the pedals, correct? In that case, I think octal latches might be

I think you should probably look into shift registers further, it may
serve your purpose. Remember that midi itself is just a TTL stream at
31.25 Kbaud, and it seems to handle a fairly large degree of complexity.

> the best way to go. Judging from your math, I could hook up 8
> independent switches at a time on the 16 IO pins. Does that mean there
> is no way to have a common ground? If I wanted to represent all 12

It is a common ground, the way latching works is, you have, say 8 toggles
and 8 input states on 8 latches. When you toggle the special 'latch' bit
on the latch, the information stored on the latches flows into the 8
inputs, so you have sort of a register/offset approach where you can view
groups of 8 I/O lines in subgroups of 8 at a time.

> tones, I would have to think in "registers" more than octaves, for a
> third of an octave would actually be one register higher, if you
> follow. I could develop a system with only 8 tones per octave (major
> scale) and transpose that to the correct key, as long as all the notes
> stayed in that key.

You always play without accidentals? [noparse]:)[/noparse]

>
> But now I'm just brainstorming in front of all of you. Maybe someone
> could help me decide what kind of system to use from the above ideas.
> If all this seems a little far-reaching, I can go to my backup plan of
> wiring this board to one of my two allmighty Casio SK-1's. An un-bent
> unit wouldn't produce tones low enough for what I want, but this is no
> un-bent unit... No, my friends, this beast is your new savior.
>
> But that is neither here nor there. Thanks a lot!
> ~Sam Kronick
>
>
> --- In basicstamps@yahoogroups.com, "Sean T. Lamont .lost."
> <lamont@a...> wrote:
> >
> > There are many ways to multiplex I/O. I haven't worked extensively with
> > shift registers, but basically they allow input and output states to
> > transmit using TTL pulses over a single I/O line. You could also use
> octal
> > latches, which allow you to view switches a bank of 8 at a time (I
> used a
> > BS2 and 8 octal latches to multiplex 64 I/O lines off of the 16 I/O
> > pins...)
> >
> > Another thing that might be pretty useful to consider is looking at
> a PS2
> > driver and hacking a standard keyboard for the 110 switches. You're
> > unlikely to be able to get velocity or poly-pressure data for any of
> these
> > things.
> >
> > I'm sort of curious why you want to recreate a cheap MIDI keyboard,
> > though. MIDI is much more interesting to play with, I find, when you're
> > building devices that are uncommon.
> >
> >
> > On Tue, 9 Mar 2004, captaink1234 wrote:
> >
> > > "What I would recommend for the original poster is that he figure
> out some
> > > way of multiplexing the inputs. (shift registers or something)"
> > >
> > > I think that's what I'm looking for... The 26 pedals/keys cannot be
> > > connected completely individually, correct? So, by "shift registers",
> > > do you mean to have each key trigger one of twelve inputs for the
> > > correct note name and then simultaneously switch the correct octave to
> > > play? This wouldn't do very well with polyphony, but I think it could
> > > work. Of course, if you meant something entirely different, share
> > > that, too :-)
> > >
> > > Now, before I buy one of these seemingly wonderful microcontrollers, I
> > > want to understand how it would work in conjunction with what I'm
> > > looking to do. I'm looking at the BS2 which has 24 pins. To have a
> > > "switch" type event, would I simply connect one wire to one pin, and
> > > another to a ground pin, and upon contact of the two wires the program
> > > could read it? How many of these switcherthingies could I have on one
> > > BS2? Would I need any fancy resistors or anything between the switches
> > > and pins?
> > >
> > > Right now, the only experience I have with these Stamps is very
> > > limited contact with the BS2sx in an IFI Robotics Isaac 16 Robot
> > > Controller (http://www.ifirobotics.com) and that seems to read all the
> > > neat little inputs it has set up for me with great ease. I became
> > > interested in the Stamps upon realizing what was inside so many of
> > > these killing machines that we trusted our very lives to.
> > >
> > > Well, thanks again,
> > > ~Sam Kronick
> > >
> > >
> > > --- In basicstamps@yahoogroups.com, "Sean T. Lamont .lost."
> > > <lamont@a...> wrote:
> > > >
> > > > I want to completely disagree with this.
> > > >
> > > > Please reference the following url:
> > > >
> > > > http://www.zenchemical.com/burningman/lightwave/
> > > >
> > > > This was a project I put together that was at number of art
> events ; the
> > > > most recently was a little over year ago at the string cheese
> incident
> > > > show in san franscisco. The fundamental basis for it is converting
> > > > optical / electrical signals into midi. The conversion boxes are
> > > > completely based on BS2.
> > > >
> > > > What I would recommend for the original poster is that he figure out
> > > some
> > > > way of multiplexing the inputs. (shift registers or something)
> The midi
> > > > output should be very straightforward. For your reference,
> instead of
> > > > using 31.25 kbaud, which is the spec, I had to use "32768" baud
> on the
> > > > BS2. I'm not precisely sure why, but there it is.
> > > >
> > > > On Fri, 5 Mar 2004, John Remington wrote:
> > > >
> > > > > MIDI needs something like 31.8k baud, I don't think you'll get
> there
> > > > > with these devices. 9600 is tops for a BS2, it looks like the
> BS2SX
> > > > > might do double that. You'll need to go to micro controller that
> > > > > doesn't do the language interpretation, that usually means
> learning
> > > > > assembly or something more difficult than P Basic.
> > > > >
> > > > >
> > > > >
> > > > > --- captaink1234 <captaink1234@y...> wrote:
> > > > > > Hello all,
> > > > > > I've recently acquired the pedal board to an old electric
> organ that
> > > > > > I would like to MIDIfy. I've found a few resources online
> > > > > > (http://www.audiomulch.com/midipic/ mainly) that lead me to
> believe
> > > > > > this could be done with a BASIC Stamp. I haven't worked with
> these
> > > > > > before, but I've done some programming and learn relatively
> fast. I
> > > > > > think this project seems like a good first with the Stamps.
> > > > > >
> > > > > > The page I mentioned earlier
> (http://www.audiomulch.com/midipic/)
> > > > > > talks mainly about creating a MIDI control-signal sending
> device. I
> > > > > > want to be able to hook up about 26 switches or contacts
> from the
> > > > > > pedals and send MIDI note on/off info. I might be able to
> modify the
> > > > > > source code
> (http://www.interaccess.org/arg/arg-knowledge/MIDI.BS2)
> > > > > > that was provided to work with the switches/contacts I speak of
> > > > > > rather than analog inputs (potentometers, etc) which it
> currently
> > > > > > does. I could likely work the software end if I could have a
> little
> > > > > > help hooking up the switches. I know the BASIC Stamp II only
> has 16
> > > > > > pins, but could I hook up more inputs? There are 26 pedals,
> and I
> > > > > > would like to utilize them all, if possible. The Stamp II
> seems the
> > > > > > Stamp most in my working price range, but if it doesn't fit the
> > > bill,
> > > > > >
> > > > > > I would consider something with more capabilities.
> > > > > >
> > > > > > I guess I'm just a little fuzzy about how inputs and such
> interface
> > > > > > with the pins on the controller and then the software. If
> anyone has
> > > > > > any advice or expertise they can offer, I would appreciate
> it. If
> > > > > > anyone has attempted a MIDI pedalboard/keyboard type controller,
> > > > > > their wisdom would be immensely helpful.
> > > > > >
> > > > > > Thanks!
> > > > > > ~Sam
> > > > > >
> > > > > > P.S. I think if this works, I might try to salvage the rest
> of this
> > > > > > organ... I guess it works fine except some idiotic kids bashed
> > > up all
> > > > > >
> > > > > > the keys. I was thinking maybe a MIDI-in device so I could
> run the
> > > > > > thing from an external MIDI keyboard. Maybe something else is in
> > > line
> > > > > >
> > > > > > there, though.
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > > To UNSUBSCRIBE, just send mail to:
> > > > > > basicstamps-unsubscribe@yahoogroups.com
> > > > > > from the same email address that you subscribed. Text in the
> > > Subject
> > > > > > and Body of the message will be ignored.
> > > > > >
> > > > > > Yahoo! Groups Links
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > >
> > > > >
> > > > > __________________________________
> > > > > Do you Yahoo!?
> > > > > Yahoo! Search - Find what you're looking for faster
> > > > > http://search.yahoo.com
> > > > >
> > > > >
> > > > > To UNSUBSCRIBE, just send mail to:
> > > > > basicstamps-unsubscribe@yahoogroups.com
> > > > > from the same email address that you subscribed. Text in the
> > > Subject and Body of the message will be ignored.
> > > > >
> > > > > Yahoo! Groups Links
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > >
> > > > Sean T. Lamont, Chief Mad Scientist |-- lamont@a...
> > > > Zen Chemical Productions |--
> > > http://www.zenchemical.com
> > > > Fabricators of Unnecessary Amazement
> > >
> > >
> > >
> > >
> > > To UNSUBSCRIBE, just send mail to:
> > > basicstamps-unsubscribe@yahoogroups.com
> > > from the same email address that you subscribed. Text in the
> Subject and Body of the message will be ignored.
> > >
> > > Yahoo! Groups Links
> > >
> > >
> > >
> > >
> > >
> > >
> >
> > Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
> > Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma -
> Bremerton
> > email: lamont@a... WWW: http://www.serv.net
> > "Do not fear mistakes, There Are None" - Miles Davis
>
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and Body
of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>
>

Sean T. Lamont, Chief Mad Scientist |-- lamont@a...
Zen Chemical Productions |-- http://www.zenchemical.com
Fabricators of Unnecessary Amazement

Archiver

If I am not mistaken, using a shift register system would require
additional hardware, no? It would also likely require more advanced
programming of the Stamp than I wish to do. I'm thinking simple right now.

Let me know if the following plan has any flaws or if there is a
better way to do the same thing without much more complexity:
I've got 25 or 26 pedals. The BASIC Stamp II has 16 IO pins. Each
pedal would act as a simple switch when depressed. The bottom of the
pedal would contact with the base, completing two circuit. One would
run from one of 12 IO pins (representing the pitch) to the ground pin.
The other circuit that would be completed would run from one of 3 IO
pins (representing the octave) to the ground pin. From the two
complete circuits, the PBASIC program would recieve two switch "on"
signals. It would use these (pitch and octave) to generate the correct
MIDI instruction and send it via SEROUT on the remaining IO pin. If I
figure correctly, I would get three full octaves of 12 notes apiece,
giving me 36 possible pedals. I could, theoretically, program and wire
the extra inputs to generate MIDI control signals.

Once again, thank you for the time you take to answer my questions. I
may not be describing my ideas with complete clarity, but I hope
they're getting across.

Thanks!
~Sam Kronick


--- In basicstamps@yahoogroups.com, "Sean T. Lamont .lost."
<lamont@a...> wrote:
> On Fri, 12 Mar 2004, captaink1234 wrote:
>
> >
> > Based on the application I'm looking at, polyphony would be nice,
> > velocity sensitivity completely unneccessary. Monophony would be
> > entirely acceptable if I could reliably play the pedals without
> > accidentally hitting one on either side of the tone I wished to play.
> > I'm sure I could program it to not play just the last pedal pressed,
> > but the last pedal pressed that is still being held down. Due to the
> > potential complexity of such a system and the number of times it would
> > need be duplicated, TTL pulses and such seems out of the question. I
> > would need a device/circuit that would create the right pulse for each
> > of the pedals, correct? In that case, I think octal latches might be
>
> I think you should probably look into shift registers further, it may
> serve your purpose. Remember that midi itself is just a TTL stream at
> 31.25 Kbaud, and it seems to handle a fairly large degree of complexity.
>
> > the best way to go. Judging from your math, I could hook up 8
> > independent switches at a time on the 16 IO pins. Does that mean there
> > is no way to have a common ground? If I wanted to represent all 12
>
> It is a common ground, the way latching works is, you have, say 8
toggles
> and 8 input states on 8 latches. When you toggle the special 'latch' bit
> on the latch, the information stored on the latches flows into the 8
> inputs, so you have sort of a register/offset approach where you can
view
> groups of 8 I/O lines in subgroups of 8 at a time.
>
> > tones, I would have to think in "registers" more than octaves, for a
> > third of an octave would actually be one register higher, if you
> > follow. I could develop a system with only 8 tones per octave (major
> > scale) and transpose that to the correct key, as long as all the notes
> > stayed in that key.
>
> You always play without accidentals? [noparse]:)[/noparse]
>
> >
> > But now I'm just brainstorming in front of all of you. Maybe someone
> > could help me decide what kind of system to use from the above ideas.
> > If all this seems a little far-reaching, I can go to my backup plan of
> > wiring this board to one of my two allmighty Casio SK-1's. An un-bent
> > unit wouldn't produce tones low enough for what I want, but this is no
> > un-bent unit... No, my friends, this beast is your new savior.
> >
> > But that is neither here nor there. Thanks a lot!
> > ~Sam Kronick
> >
> >
> > --- In basicstamps@yahoogroups.com, "Sean T. Lamont .lost."
> > <lamont@a...> wrote:
> > >
> > > There are many ways to multiplex I/O. I haven't worked
extensively with
> > > shift registers, but basically they allow input and output states to
> > > transmit using TTL pulses over a single I/O line. You could also use
> > octal
> > > latches, which allow you to view switches a bank of 8 at a time (I
> > used a
> > > BS2 and 8 octal latches to multiplex 64 I/O lines off of the 16 I/O
> > > pins...)
> > >
> > > Another thing that might be pretty useful to consider is looking at
> > a PS2
> > > driver and hacking a standard keyboard for the 110 switches. You're
> > > unlikely to be able to get velocity or poly-pressure data for any of
> > these
> > > things.
> > >
> > > I'm sort of curious why you want to recreate a cheap MIDI keyboard,
> > > though. MIDI is much more interesting to play with, I find, when
you're
> > > building devices that are uncommon.
> > >
> > >
> > > On Tue, 9 Mar 2004, captaink1234 wrote:
> > >
> > > > "What I would recommend for the original poster is that he figure
> > out some
> > > > way of multiplexing the inputs. (shift registers or something)"
> > > >
> > > > I think that's what I'm looking for... The 26 pedals/keys
cannot be
> > > > connected completely individually, correct? So, by "shift
registers",
> > > > do you mean to have each key trigger one of twelve inputs for the
> > > > correct note name and then simultaneously switch the correct
octave to
> > > > play? This wouldn't do very well with polyphony, but I think
it could
> > > > work. Of course, if you meant something entirely different, share
> > > > that, too :-)
> > > >
> > > > Now, before I buy one of these seemingly wonderful
microcontrollers, I
> > > > want to understand how it would work in conjunction with what I'm
> > > > looking to do. I'm looking at the BS2 which has 24 pins. To have a
> > > > "switch" type event, would I simply connect one wire to one
pin, and
> > > > another to a ground pin, and upon contact of the two wires the
program
> > > > could read it? How many of these switcherthingies could I have
on one
> > > > BS2? Would I need any fancy resistors or anything between the
switches
> > > > and pins?
> > > >
> > > > Right now, the only experience I have with these Stamps is very
> > > > limited contact with the BS2sx in an IFI Robotics Isaac 16 Robot
> > > > Controller (http://www.ifirobotics.com) and that seems to read
all the
> > > > neat little inputs it has set up for me with great ease. I became
> > > > interested in the Stamps upon realizing what was inside so many of
> > > > these killing machines that we trusted our very lives to.
> > > >
> > > > Well, thanks again,
> > > > ~Sam Kronick
> > > >
> > > >
> > > > --- In basicstamps@yahoogroups.com, "Sean T. Lamont .lost."
> > > > <lamont@a...> wrote:
> > > > >
> > > > > I want to completely disagree with this.
> > > > >
> > > > > Please reference the following url:
> > > > >
> > > > > http://www.zenchemical.com/burningman/lightwave/
> > > > >
> > > > > This was a project I put together that was at number of art
> > events ; the
> > > > > most recently was a little over year ago at the string cheese
> > incident
> > > > > show in san franscisco. The fundamental basis for it is
converting
> > > > > optical / electrical signals into midi. The conversion boxes are
> > > > > completely based on BS2.
> > > > >
> > > > > What I would recommend for the original poster is that he
figure out
> > > > some
> > > > > way of multiplexing the inputs. (shift registers or something)
> > The midi
> > > > > output should be very straightforward. For your reference,
> > instead of
> > > > > using 31.25 kbaud, which is the spec, I had to use "32768" baud
> > on the
> > > > > BS2. I'm not precisely sure why, but there it is.
> > > > >
> > > > > On Fri, 5 Mar 2004, John Remington wrote:
> > > > >
> > > > > > MIDI needs something like 31.8k baud, I don't think you'll get
> > there
> > > > > > with these devices. 9600 is tops for a BS2, it looks like the
> > BS2SX
> > > > > > might do double that. You'll need to go to micro
controller that
> > > > > > doesn't do the language interpretation, that usually means
> > learning
> > > > > > assembly or something more difficult than P Basic.
> > > > > >
> > > > > >
> > > > > >
> > > > > > --- captaink1234 <captaink1234@y...> wrote:
> > > > > > > Hello all,
> > > > > > > I've recently acquired the pedal board to an old electric
> > organ that
> > > > > > > I would like to MIDIfy. I've found a few resources online
> > > > > > > (http://www.audiomulch.com/midipic/ mainly) that lead me to
> > believe
> > > > > > > this could be done with a BASIC Stamp. I haven't worked with
> > these
> > > > > > > before, but I've done some programming and learn relatively
> > fast. I
> > > > > > > think this project seems like a good first with the Stamps.
> > > > > > >
> > > > > > > The page I mentioned earlier
> > (http://www.audiomulch.com/midipic/)
> > > > > > > talks mainly about creating a MIDI control-signal sending
> > device. I
> > > > > > > want to be able to hook up about 26 switches or contacts
> > from the
> > > > > > > pedals and send MIDI note on/off info. I might be able to
> > modify the
> > > > > > > source code
> > (http://www.interaccess.org/arg/arg-knowledge/MIDI.BS2)
> > > > > > > that was provided to work with the switches/contacts I
speak of
> > > > > > > rather than analog inputs (potentometers, etc) which it
> > currently
> > > > > > > does. I could likely work the software end if I could have a
> > little
> > > > > > > help hooking up the switches. I know the BASIC Stamp II only
> > has 16
> > > > > > > pins, but could I hook up more inputs? There are 26 pedals,
> > and I
> > > > > > > would like to utilize them all, if possible. The Stamp II
> > seems the
> > > > > > > Stamp most in my working price range, but if it doesn't
fit the
> > > > bill,
> > > > > > >
> > > > > > > I would consider something with more capabilities.
> > > > > > >
> > > > > > > I guess I'm just a little fuzzy about how inputs and such
> > interface
> > > > > > > with the pins on the controller and then the software. If
> > anyone has
> > > > > > > any advice or expertise they can offer, I would appreciate
> > it. If
> > > > > > > anyone has attempted a MIDI pedalboard/keyboard type
controller,
> > > > > > > their wisdom would be immensely helpful.
> > > > > > >
> > > > > > > Thanks!
> > > > > > > ~Sam
> > > > > > >
> > > > > > > P.S. I think if this works, I might try to salvage the rest
> > of this
> > > > > > > organ... I guess it works fine except some idiotic kids
bashed
> > > > up all
> > > > > > >
> > > > > > > the keys. I was thinking maybe a MIDI-in device so I could
> > run the
> > > > > > > thing from an external MIDI keyboard. Maybe something
else is in
> > > > line
> > > > > > >
> > > > > > > there, though.
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > > >
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in the
> > > > Subject
> > > > > > > and Body of the message will be ignored.
> > > > > > >
> > > > > > > Yahoo! Groups Links
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > >
> > > > > >
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> > > > > >
> > > > >
> > > > > Sean T. Lamont, Chief Mad Scientist |-- lamont@a...
> > > > > Zen Chemical Productions |--
> > > > http://www.zenchemical.com
> > > > > Fabricators of Unnecessary Amazement
> > > >
> > > >
> > > >
> > > >
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> > > > Yahoo! Groups Links
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > >
> > > Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc.
(ServNet)
> > > Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma -
> > Bremerton
> > > email: lamont@a... WWW: http://www.serv.net
> > > "Do not fear mistakes, There Are None" - Miles Davis
> >
> >
> >
> >
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> >
> >
>
> Sean T. Lamont, Chief Mad Scientist |-- lamont@a...
> Zen Chemical Productions |--
http://www.zenchemical.com
> Fabricators of Unnecessary Amazement