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Need more pots

ArchiverArchiver Posts: 46,084
edited 2003-03-09 18:26 in General Discussion
Hello ,I am Corne, a new basicstamp-freak

i am building a midi-controller , and have 1 question.????

who knows how I can use more pots with stamp2

I have already a lot of knobs and leds with the use of 74hc165/74hc595 , now
I need more pots and faders for my midi-mixer.

already ports in use:
3 in for knobs
3 out for leds
1 out for midi out

I can use the other 9 for pots or faders but wanted more faders/pots ????


thanks !!!!!!!!!!!!!! CORNE


[noparse][[/noparse]Non-text portions of this message have been removed]

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2003-03-09 13:43
    Possibilities:
    1. ADC0831 is an 8-pin dip, reads one 0..5V signal,
    needs 2 Stamp pins, has 8-bit resolution (255 steps)
    2. ADC0832 is same package, reads two 0..5V signals,
    same 2 Stamp pins.
    3. The ADC08xx family does have a package which has
    8 A/D converters in it, same 2 Stamp pins.
    4. Any other off the shelf A/D converter which supports
    'SPI' (serial peripheral interface).

    Or:
    You can use the RCTime command, with a capacitor
    for each channel -- see the manual, but this takes
    one I/O pin per Analog signal.


    --- In basicstamps@yahoogroups.com, "Schijndel197"
    <schijndel197@z...> wrote:
    > Hello ,I am Corne, a new basicstamp-freak
    >
    > i am building a midi-controller , and have 1 question.????
    >
    > who knows how I can use more pots with stamp2
    >
    > I have already a lot of knobs and leds with the use of
    74hc165/74hc595 , now
    > I need more pots and faders for my midi-mixer.
    >
    > already ports in use:
    > 3 in for knobs
    > 3 out for leds
    > 1 out for midi out
    >
    > I can use the other 9 for pots or faders but wanted more
    faders/pots ????
    >
    >
    > thanks !!!!!!!!!!!!!! CORNE
    >
    >
    > [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2003-03-09 14:51
    Corne,

    The easiest way is to get an A/D converter with as many inputs as possible.
    Look at the Maxim website, they make lots of A/Ds, and I know they have one
    with 8 channels at least. Each A/D will take two pins from your Stamp.

    Hope this helps,

    Jonathan

    www.madlabs.info

    Original Message
    From: "Schijndel197" <schijndel197@z...>
    To: <basicstamps@yahoogroups.com>
    Sent: Sunday, March 09, 2003 5:25 AM
    Subject: [noparse][[/noparse]basicstamps] NEED MORE POTS


    > Hello ,I am Corne, a new basicstamp-freak
    >
    > i am building a midi-controller , and have 1 question.????
    >
    > who knows how I can use more pots with stamp2
    >
    > I have already a lot of knobs and leds with the use of 74hc165/74hc595 ,
    now
    > I need more pots and faders for my midi-mixer.
    >
    > already ports in use:
    > 3 in for knobs
    > 3 out for leds
    > 1 out for midi out
    >
    > I can use the other 9 for pots or faders but wanted more faders/pots ????
    >
    >
    > thanks !!!!!!!!!!!!!! CORNE
    >
    >
    > [noparse][[/noparse]Non-text portions of this message have been removed]
    >
    >
    > 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.
    >
    >
    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    >
    >
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2003-03-09 15:57
    Corne,
    You already have the basic knowledge tools you need to make
    a simple multiplexing scheme for multiple POTS. You stated your
    use of a 74165 which is an 8-bit input P2S. Reverse of that, what
    you can use is a 74164 which is an 8-bit output S2P. Now here is
    where I'm going with this... Looking at one of the BS2 pdf
    manuals on using POTS you basically have a circuit as follows....

    220
    I/O >---/\/\---o
    .1uF | 10K
    +5V >----||----o----/\/\----o
    |
    o
    < GND

    ...Now, imagine what it would take to multiplex this circuit,
    consider two identical circuits

    220
    I/O >---/\/\---o
    .1uF | 10K
    +5V >----||----o----/\/\----o
    |
    o
    < GND
    |
    +5V >----||----o----/\/\----o
    .1uF | 10K
    I/O >---/\/\---o
    220


    ...The idea is to look for COMMON nodes that can be "broken" and
    tied into a 74164 for individual control. Now you say, but I don't
    want a separate 220 Ohm resistor and a capacitor for each POT I want
    to instantiate. Fine, you can simplify this circuit into using only
    one 220 Ohm, one Capacitor, up to 8 pots, and one 74164 IC with the
    addition of one diode per POT (maximum 8 diodes)

    220
    I/O >---/\/\---o
    .1uF | 10K
    +5V >----||----o----/\/\----o
    | | D1
    | o
    >|
    < 74164 Output 1
    |
    | 10K
    o----/\/\----o
    | | D2
    | o
    >|
    < 74164 Output 2
    |
    | 10K
    o----/\/\----o
    | | D3
    | o
    >|
    < 74164 Output 3
    |
    | 10K
    o----/\/\----o
    | | D4
    | o
    >|
    < 74164 Output 4
    |
    | 10K
    o----/\/\----o
    | | D5
    | o
    >|
    < 74164 Output 5
    |
    | 10K
    o----/\/\----o
    | | D6
    | o
    >|
    < 74164 Output 6
    |
    | 10K
    o----/\/\----o
    | | D7
    | o
    >|
    < 74164 Output 7
    |
    | 10K
    o----/\/\----o
    | D8
    o
    >|
    < 74164 Output 8

    D1-D8 generic (Rat-Shack 50 pack)

    Design Note:
    If you have long leads (> 6 inches) between 74164 and POTS,
    use twisted pair with one connection tied to ground, keeping
    diodes close to POT. Keep 220 Ohm resistor and .1uF CAP close
    to BS2 I/O. Also use twisted pair from here to POTS and
    connect one terminal of the twisted pair to ground if POTS are
    more that 6 inches away.

    Program Note:
    The only thing you need to be aware of in "code" is to ensure
    that ONLY one output of the 74164 is LOW at a time before you
    read the POT, otherwise for each pin of the 74164 that is LOW,
    you will be reading a combination of those POTS in parallel.
    ....However that could be a desired effect dependign on your
    application.

    Have fun!!

    Beau Schwabe











    > Corne,
    >
    > The easiest way is to get an A/D converter with as many inputs as
    possible.
    > Look at the Maxim website, they make lots of A/Ds, and I know they
    have one
    > with 8 channels at least. Each A/D will take two pins from your Stamp.
    >
    > Hope this helps,
    >
    > Jonathan
    >
    > www.madlabs.info
    >
    >
    Original Message
    > From: "Schijndel197" <schijndel197@z...>
    > To: <basicstamps@yahoogroups.com>
    > Sent: Sunday, March 09, 2003 5:25 AM
    > Subject: [noparse][[/noparse]basicstamps] NEED MORE POTS
    >
    >
    > > Hello ,I am Corne, a new basicstamp-freak
    > >
    > > i am building a midi-controller , and have 1 question.????
    > >
    > > who knows how I can use more pots with stamp2
    > >
    > > I have already a lot of knobs and leds with the use of
    74hc165/74hc595 ,
    > now
    > > I need more pots and faders for my midi-mixer.
    > >
    > > already ports in use:
    > > 3 in for knobs
    > > 3 out for leds
    > > 1 out for midi out
    > >
    > > I can use the other 9 for pots or faders but wanted more
    faders/pots ????
    > >
    > >
    > > thanks !!!!!!!!!!!!!! CORNE
    > >
    > >
    > > [noparse][[/noparse]Non-text portions of this message have been removed]
    > >
    > >
    > > 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.
    > >
    > >
    > > Your use of Yahoo! Groups is subject to
    http://docs.yahoo.com/info/terms/
    > >
    > >
    > >
    > >
  • ArchiverArchiver Posts: 46,084
    edited 2003-03-09 16:21
    I use a TLC2543 ADC. 12 bit with 11 inputs. using SPI - 4 pins for one ADC
    but as you add more ADCs they each only need one pin. Din, Dout, and clock
    can be shared, only CS needs a seperate pin per ADC.

    My 'lectronic Newb site http://members.shaw.ca/pmeloy/
    Original Message
    From: "Jonathan Peakall" <jpeakall@m...>
    To: <basicstamps@yahoogroups.com>
    Sent: Sunday, March 09, 2003 6:51 AM
    Subject: Re: [noparse][[/noparse]basicstamps] NEED MORE POTS


    > Corne,
    >
    > The easiest way is to get an A/D converter with as many inputs as
    possible.
    > Look at the Maxim website, they make lots of A/Ds, and I know they have
    one
    > with 8 channels at least. Each A/D will take two pins from your Stamp.
    >
    > Hope this helps,
    >
    > Jonathan
    >
    > www.madlabs.info
    >
    >
    Original Message
    > From: "Schijndel197" <schijndel197@z...>
    > To: <basicstamps@yahoogroups.com>
    > Sent: Sunday, March 09, 2003 5:25 AM
    > Subject: [noparse][[/noparse]basicstamps] NEED MORE POTS
    >
    >
    > > Hello ,I am Corne, a new basicstamp-freak
    > >
    > > i am building a midi-controller , and have 1 question.????
    > >
    > > who knows how I can use more pots with stamp2
    > >
    > > I have already a lot of knobs and leds with the use of 74hc165/74hc595 ,
    > now
    > > I need more pots and faders for my midi-mixer.
    > >
    > > already ports in use:
    > > 3 in for knobs
    > > 3 out for leds
    > > 1 out for midi out
    > >
    > > I can use the other 9 for pots or faders but wanted more faders/pots
    ????
    > >
    > >
    > > thanks !!!!!!!!!!!!!! CORNE
    > >
    > >
    > > [noparse][[/noparse]Non-text portions of this message have been removed]
    > >
    > >
    > > 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.
    > >
    > >
    > > Your use of Yahoo! Groups is subject to
    http://docs.yahoo.com/info/terms/
    > >
    > >
    > >
    > >
    >
    >
    > 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.
    >
    >
    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2003-03-09 18:26
    Corne,
    I noticed the ASCII Art did not go through correctly on my last post,
    so here is a link to a schematic for an 8-POT 3-I/O design....

    http://www.angelfire.com/wizard/y2kbc/schematic/8P3IO.gif

    ...have fun!

    Beau Schwabe


    >
    > > Corne,
    > >
    > > The easiest way is to get an A/D converter with as many inputs as
    > possible.
    > > Look at the Maxim website, they make lots of A/Ds, and I know they
    > have one
    > > with 8 channels at least. Each A/D will take two pins from your Stamp.
    > >
    > > Hope this helps,
    > >
    > > Jonathan
    > >
    > > www.madlabs.info
    > >
    > >
    Original Message
    > > From: "Schijndel197" <schijndel197@z...>
    > > To: <basicstamps@yahoogroups.com>
    > > Sent: Sunday, March 09, 2003 5:25 AM
    > > Subject: [noparse][[/noparse]basicstamps] NEED MORE POTS
    > >
    > >
    > > > Hello ,I am Corne, a new basicstamp-freak
    > > >
    > > > i am building a midi-controller , and have 1 question.????
    > > >
    > > > who knows how I can use more pots with stamp2
    > > >
    > > > I have already a lot of knobs and leds with the use of
    > 74hc165/74hc595 ,
    > > now
    > > > I need more pots and faders for my midi-mixer.
    > > >
    > > > already ports in use:
    > > > 3 in for knobs
    > > > 3 out for leds
    > > > 1 out for midi out
    > > >
    > > > I can use the other 9 for pots or faders but wanted more
    > faders/pots ????
    > > >
    > > >
    > > > thanks !!!!!!!!!!!!!! CORNE
    > > >
    > > >
    > > > [noparse][[/noparse]Non-text portions of this message have been removed]
    > > >
    > > >
    > > > 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.
    > > >
    > > >
    > > > Your use of Yahoo! Groups is subject to
    > http://docs.yahoo.com/info/terms/
    > > >
    > > >
    > > >
    > > >
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