Control 150 leds
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Posts: 46,084
Hello,
I have a huge problem,,, I have to control with one
BS2 more than 120 LEDS Independitly. For example I
want to turn on the last (120) led at the same time
the first led (1), then I want to turn on all leds,,,
then the odds, then even, etc...etc... I need to have
control of each led independiently.
I have used a 8 bit binary serial driver (from allegro
UCN5821A that I think is similar to the 74HC595
Shiftregister) but you know I have to use 3 pins of
the BS2 for clock,data and strobe,,,, so with 16 pins
I only have control of 5 5821 with a total of 40 leds.
PLEASE HELP ME!!
Regards,
Alejandro Vazque
__________________________________________________
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Yahoo! Sports - live college hoops coverage
http://sports.yahoo.com/
I have a huge problem,,, I have to control with one
BS2 more than 120 LEDS Independitly. For example I
want to turn on the last (120) led at the same time
the first led (1), then I want to turn on all leds,,,
then the odds, then even, etc...etc... I need to have
control of each led independiently.
I have used a 8 bit binary serial driver (from allegro
UCN5821A that I think is similar to the 74HC595
Shiftregister) but you know I have to use 3 pins of
the BS2 for clock,data and strobe,,,, so with 16 pins
I only have control of 5 5821 with a total of 40 leds.
PLEASE HELP ME!!
Regards,
Alejandro Vazque
__________________________________________________
Do You Yahoo!?
Yahoo! Sports - live college hoops coverage
http://sports.yahoo.com/
Comments
Actually, with this setup, you can control 112 LEDs. Here's why:
The clock and data lines are on the 3-wire bus; all devices can share
the clock and data lines. The chip select's however need to go to the
individual devices. You can use 2 stamp pins for DATA and CLOCK.
Connect all of the data pins on the shift registers to the same stamp
pin (DATA). Connect all of the clock pins on the shift registers to
the same stamp pin (CLOCK). The remaining 14 stamp pins can then
connect to each shift registers CS pin. (Then you can control 14x8 or
112 LEDs). You use shiftout as you normally would; just make sure to
use the correct CS to activate the shift register you need.
That gets you closer, but still leaves you a little short.... You
could use something like a MAX349 and cascade the last two devices
together. The datasheet (page16, available at http://www.maxim-
ic.com) shows how this is done. You would still have the same DATA
and CLOCK, as well as the 14 CS lines. The only difference would be
that the last MUX would be daisy chained together. That would give
you the extra 8, for a total of 120.
Hope this helps....
--Jeff
Add a RTC, 256k EEPROM and an I2C buss to your BS2, e, sx or p!
http://www.high-techgarage.com/products/timekeeper3.php
--- In basicstamps@y..., Alejandro Vazquez <alexvazquez@y...> wrote:
> Hello,
>
> I have a huge problem,,, I have to control with one
> BS2 more than 120 LEDS Independitly. For example I
> want to turn on the last (120) led at the same time
> the first led (1), then I want to turn on all leds,,,
> then the odds, then even, etc...etc... I need to have
> control of each led independiently.
>
> I have used a 8 bit binary serial driver (from allegro
> UCN5821A that I think is similar to the 74HC595
> Shiftregister) but you know I have to use 3 pins of
> the BS2 for clock,data and strobe,,,, so with 16 pins
> I only have control of 5 5821 with a total of 40 leds.
>
>
> PLEASE HELP ME!!
> Regards,
> Alejandro Vazque
>
> __________________________________________________
> Do You Yahoo!?
> Yahoo! Sports - live college hoops coverage
> http://sports.yahoo.com/
I've made large arrays where I controlled individual LEDs using the Toshiba
TB62706BN. I get them through Marktech Opto but they may be available
elsewhere.
http://www.marktechopto.com/PDFs/Toshiba/ACF7BE.pdf
These series of drivers (TB62706, TB62708, etc) have a serial output and
can work with one data line, one clock line and signal latch line so you
can have all the LEDs change together. You don't need limiting resistors
with this driver and can set the current through a single current
programming resistor to the chip. The remainder of the series can be
found here:
http://www.marktechopto.com/catalog/Catalog.cfm?Drill_Level=Series&DeptID=2100&S\
eriesID=1286
Good luck,
Mike
At 11:56 AM 3/14/2002 -0800, you wrote:
>Hello,
>
>I have a huge problem,,, I have to control with one
>BS2 more than 120 LEDS Independitly. For example I
>want to turn on the last (120) led at the same time
>the first led (1), then I want to turn on all leds,,,
>then the odds, then even, etc...etc... I need to have
>control of each led independiently.
>
>I have used a 8 bit binary serial driver (from allegro
>UCN5821A that I think is similar to the 74HC595
>Shiftregister) but you know I have to use 3 pins of
>the BS2 for clock,data and strobe,,,, so with 16 pins
>I only have control of 5 5821 with a total of 40 leds.
>
>
>PLEASE HELP ME!!
>Regards,
>Alejandro Vazque
>
>__________________________________________________
>Do You Yahoo!?
>Yahoo! Sports - live college hoops coverage
>http://sports.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.
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
_________________________________
Mike Walsh
walsh@c...
California Institute of Technology
Biology Electronics Shop
MS 216-76
Pasadena, CA 91125
626-395-6825 , FAX 626-584-1654
237 Beckman Behavioral Biology Bldg.
[noparse][[/noparse]Non-text portions of this message have been removed]
After reading Gene's suggestion (which is much, much simpler than
what I originally proposed), I remembered Maxim's MAX7219/MAX7221.
This device can control up to 8 7-segment LEDs or 64 individual LEDs.
This would only require 3 stamp pins (Data, clock and CS). Page 13 of
the data sheet shows how they can be cascaded. You can probably get
samples of this chip from Maxim's website.
If you need help with the software, I have a tutorial for the MAX7221
at: http://www.high-techgarage.com/tutorial/max7221.php. You will
also find a link to the datasheet there.
Good luck,
--Jeff
A RTC, 128k EEPROM and an I2C bus in a tiny SIP package!
http://www.high-techgarage.com/products/mightymite.php
--- In basicstamps@y..., Alejandro Vazquez <alexvazquez@y...> wrote:
> Hello,
>
> I have a huge problem,,, I have to control with one
> BS2 more than 120 LEDS Independitly. For example I
> want to turn on the last (120) led at the same time
> the first led (1), then I want to turn on all leds,,,
> then the odds, then even, etc...etc... I need to have
> control of each led independiently.
>
> I have used a 8 bit binary serial driver (from allegro
> UCN5821A that I think is similar to the 74HC595
> Shiftregister) but you know I have to use 3 pins of
> the BS2 for clock,data and strobe,,,, so with 16 pins
> I only have control of 5 5821 with a total of 40 leds.
>
>
> PLEASE HELP ME!!
> Regards,
> Alejandro Vazque
>
> __________________________________________________
> Do You Yahoo!?
> Yahoo! Sports - live college hoops coverage
> http://sports.yahoo.com/
Maybe the MM5451? Last time I tried, I couldn't find them anywhere. Are
they still available?
Mike
At 01:33 PM 3/14/2002 -0800, you wrote:
>I don't recall the chip number off the top of my head, but Natsemi makes a
>7 segment display driver that will drive 33 individual LEDS via a 3 wire
>SPI interface. They can be daisy chained to accomodate your requirement.
>
>g.
_________________________________
Mike Walsh
walsh@c...
California Institute of Technology
Biology Electronics Shop
MS 216-76
Pasadena, CA 91125
626-395-6825 , FAX 626-584-1654
237 Beckman Behavioral Biology Bldg.
[noparse][[/noparse]Non-text portions of this message have been removed]
7 segment display driver that will drive 33 individual LEDS via a 3 wire
SPI interface. They can be daisy chained to accomodate your requirement.
g.
On Thu, 14 Mar 2002, Alejandro Vazquez wrote:
> Hello,
>
> I have a huge problem,,, I have to control with one
> BS2 more than 120 LEDS Independitly. For example I
> want to turn on the last (120) led at the same time
> the first led (1), then I want to turn on all leds,,,
> then the odds, then even, etc...etc... I need to have
> control of each led independiently.
>
> I have used a 8 bit binary serial driver (from allegro
> UCN5821A that I think is similar to the 74HC595
> Shiftregister) but you know I have to use 3 pins of
> the BS2 for clock,data and strobe,,,, so with 16 pins
> I only have control of 5 5821 with a total of 40 leds.
>
>
> PLEASE HELP ME!!
> Regards,
> Alejandro Vazque
>
> __________________________________________________
> Do You Yahoo!?
> Yahoo! Sports - live college hoops coverage
> http://sports.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.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>
--
"I'm not crazy, I'm plausibly off-nominal!"
http://www.f15sim.com - The only one of its kind.
>Hello,
>
>I have a huge problem,,, I have to control with one
>BS2 more than 120 LEDS Independitly. For example I
>want to turn on the last (120) led at the same time
>the first led (1), then I want to turn on all leds,,,
>then the odds, then even, etc...etc... I need to have
>control of each led independiently.
>
>I have used a 8 bit binary serial driver (from allegro
>UCN5821A that I think is similar to the 74HC595
>Shiftregister) but you know I have to use 3 pins of
>the BS2 for clock,data and strobe,,,, so with 16 pins
>I only have control of 5 5821 with a total of 40 leds.
How fast do the LEDs have to update? How much current are you operating
the LEDs at?
If the update rate is slow and you are operating the LEDs at 5 to 10 mA,
you can use a string of 74HC595 shift registers. 3 wires from the Stamp is
all that is required. If you need more current than the hc595s can sink,
use TPIC6C595 (same pinout as hc595) or TPIC6595. These are good for up to
100 mA or 250 mA respectively. Use sinking mode for the LEDs: anode to
Vled via the current limit resistor, cathode to the SR pin. I generally
use about 4 Vdc as the LED supply - you may want to reduce that to 3.3V to
reduce the total power dissipation. Be sure to run the HC595s from the 5V
supply - they need 5V or higher to ensure the output FET drivers are fully
enhanced.
If you need more speed, split the chain into as many serial streams as
required. You can share the clock and latch lines for all streams, with a
separate data line for each stream. But if you are trying to get really
fast update rates, the stamp is not the right tool for the job.
I drive 2 streams of 128 LEDs on one of our Pyro controllers with an update
rate of 5 milliseconds (not by a stamp, though). I could have gone longer
if I needed - 256 LEDs in 1 data stream is no problem at all.
dwayne
Dwayne Reid <dwayner@p...>
Trinity Electronics Systems Ltd Edmonton, AB, CANADA
(780) 489-3199 voice (780) 487-6397 fax
Celebrating 18 years of Engineering Innovation (1984 - 2002)
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`-' `-' `-' `-' `-' `-' `-' `-' `-'
Do NOT send unsolicited commercial email to this email address.
This message neither grants consent to receive unsolicited
commercial email nor is intended to solicit commercial email.
> After reading Gene's suggestion (which is much, much simpler than
> what I originally proposed), I remembered Maxim's MAX7219/MAX7221.
> This device can control up to 8 7-segment LEDs or 64 individual LEDs.
> This would only require 3 stamp pins (Data, clock and CS). Page 13 of
> the data sheet shows how they can be cascaded. You can probably get
> samples of this chip from Maxim's website.
>
That's a neat part Jeff. Thanks for the info. What I don't get is how
they can drive 64 LEDs from a 24 pin chip. The National part I'm thinking
of is a 40 pin package and only drives 33 (or 35, I don't recall
exactly) LEDs. Are they tieing all the cathodes together or something?
g.
--
"I'm not crazy, I'm plausibly off-nominal!"
http://www.f15sim.com - The only one of its kind.
> Gene,
> Maybe the MM5451? Last time I tried, I couldn't find them anywhere. Are
> they still available?
> Mike
>
YEs, that's the one. They're also made by another company (548?) and I
recently bought a bunch of them from Pioneer. I'm at work so I don't have
any of my notes handy.
g.
control 64 separate LED's (or 8 - 7 segment displays). I have not used it
this way. You could use 2 chips for 128 LEDs or 3 for 192 LEDs. You just need
4 I/O lines for 2 chips and 5 lines for 3 chips (or get fancy and 4 lines and
a NAND gate for 3 chips)
I am not near a data sheet (on the road) so I cant help anymore until next
week.
Alan Bradford
Plasma Technologies
be driven from the same data line. It has a data out pin. The spec sheet
shows this. That way 3 I/O pins are all you need
Alan Bradford
Plasma Technologies
> What I don't get is how they can drive 64 LEDs from a 24 pin chip.
The MAX7219 can control 64 LEDs because there are essentially 8
segments in a 7-segment display (the 8th is the decimal point). The
chip can control 8 digits. Therefore, there are 8 discrete LEDs per
digit, or 64 discrete LED's than can be lit.
-A-
F| |B
-G-
E| |C .DP
-D-
The datasheet for the MAX7219 explains this concept in a little more
detail. (You can download a copy from the "support" section of our
website, or go to www.maxim-ic.com and search for MAX7219).
--Jeff
Check out our Basic Stamp tutorials:
http://www.high-techgarage.com/tutorial/
On Thu, 14 Mar 2002, bs2web wrote:
> Hi Gene,
>
> > What I don't get is how they can drive 64 LEDs from a 24 pin chip.
>
> The MAX7219 can control 64 LEDs because there are essentially 8
> segments in a 7-segment display (the 8th is the decimal point). The
> chip can control 8 digits. Therefore, there are 8 discrete LEDs per
> digit, or 64 discrete LED's than can be lit.
>
> -A-
> F| |B
> -G-
> E| |C .DP
> -D-
>
> The datasheet for the MAX7219 explains this concept in a little more
> detail. (You can download a copy from the "support" section of our
> website, or go to www.maxim-ic.com and search for MAX7219).
>
> --Jeff
>
> Check out our Basic Stamp tutorials:
> http://www.high-techgarage.com/tutorial/
>
>
> To UNSUBSCRIBE, just send mail to:
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of the message will be ignored.
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>
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>
>
>
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
The part you most definitely need is the Allegro UCN5833. It's a serially
controlled 32-bit shift register that's about $6, and couldn't be simpler to
communicate with. You can chain multiple units together. I used it in one
of my recent projects, in which I had to control 8 7 segment scoreboard
digits:
http://www.weatherstamp.com/parnelleng/images/scbddrvr01.jpg
The additional chips on this board are Allegro 2940s, which are used to sink
the additional current required by each segment. Each "segment" consists of
3 100 mA 14V bulbs.
The datasheet for the UCN5833 is here:
http://www.allegromicro.com/sf/5833/
Matt Parnell
mail@w...
Parnell Engineering, LLC Main: 734 464 0150
http://www.weatherstamp.com Fax: 734 432 9866
37637 Five Mile Rd., #198 Pager: 517 251 7674
Livonia, MI 48154-2634 USA Cell: 734 347 3998
Original Message
From: Alejandro Vazquez [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=kG5UaTRVdludSb3M53XDTVZ-KwXerjGk4Ol78JSoLknRscbpgFjZMF1FjpPgs_V6RpX5BtXeWMtKbKUG90w0]alexvazquez@y...[/url
Sent: Thursday, March 14, 2002 2:57 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Control 150 leds
Hello,
I have a huge problem,,, I have to control with one
BS2 more than 120 LEDS Independitly. For example I
want to turn on the last (120) led at the same time
the first led (1), then I want to turn on all leds,,,
then the odds, then even, etc...etc... I need to have
control of each led independiently.
I have used a 8 bit binary serial driver (from allegro
UCN5821A that I think is similar to the 74HC595
Shiftregister) but you know I have to use 3 pins of
the BS2 for clock,data and strobe,,,, so with 16 pins
I only have control of 5 5821 with a total of 40 leds.
PLEASE HELP ME!!
Regards,
Alejandro Vazque
__________________________________________________
Do You Yahoo!?
Yahoo! Sports - live college hoops coverage
http://sports.yahoo.com/
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Plus with the right words they'll send you some samples too.
A6276ELW is a 16 output serial input driver.
UCN5832A and UCN5833A are both 32 output serial in/out drivers. Easy to
cascade these.
They also have a bunch of other drivers 7 bit and 8 bit outputs, et cetera
as well.
The 32 bit ones were a lot of fun to use. One serial output port, four chips
cascaded gave me 128 output lines. Up to 3.3 mhz serial data rate (a lot
faster than the Stamps can go). Basically, you disable the outputs, then you
load the registers with the data, and then enable the outputs. You do this
rapidly many many times a second.
Original Message
From: Alejandro Vazquez [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=x584yLFvBc3iO_s9ub3BUq4Sp8MLfstGlFCC9ti0IVoSdQdEZn7bIyckmKPdg4d6LeELFSfGR5WPARvzPax7oA]alexvazquez@y...[/url
Sent: Thursday, March 14, 2002 1:57 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Control 150 leds
Hello,
I have a huge problem,,, I have to control with one
BS2 more than 120 LEDS Independitly. For example I
want to turn on the last (120) led at the same time
the first led (1), then I want to turn on all leds,,,
then the odds, then even, etc...etc... I need to have
control of each led independiently.
I have used a 8 bit binary serial driver (from allegro
UCN5821A that I think is similar to the 74HC595
Shiftregister) but you know I have to use 3 pins of
the BS2 for clock,data and strobe,,,, so with 16 pins
I only have control of 5 5821 with a total of 40 leds.
PLEASE HELP ME!!
Regards,
Alejandro Vazque
__________________________________________________
Do You Yahoo!?
Yahoo! Sports - live college hoops coverage
http://sports.yahoo.com/
To UNSUBSCRIBE, just send mail to:
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Thanks for your help,,,
I have a question---- the BS2 is a 16 bit micro how
can I comunicate with a 32 bit device?
Ok so,, I can have control of 160 leds with 5 5833,,,
independiently but how can I connect in chain multiple
units,, do I still have control of each led?
Thanks for your help
Alejandro Vazquez
--- Matt Parnell <mail@w...> wrote:
> Alejandro,
>
> The part you most definitely need is the Allegro
> UCN5833. It's a serially
> controlled 32-bit shift register that's about $6,
> and couldn't be simpler to
> communicate with. You can chain multiple units
> together. I used it in one
> of my recent projects, in which I had to control 8 7
> segment scoreboard
> digits:
>
>
http://www.weatherstamp.com/parnelleng/images/scbddrvr01.jpg
>
> The additional chips on this board are Allegro
> 2940s, which are used to sink
> the additional current required by each segment.
> Each "segment" consists of
> 3 100 mA 14V bulbs.
>
> The datasheet for the UCN5833 is here:
>
> http://www.allegromicro.com/sf/5833/
>
> Matt Parnell
> mail@w...
> Parnell Engineering, LLC Main: 734 464 0150
> http://www.weatherstamp.com Fax: 734 432 9866
> 37637 Five Mile Rd., #198 Pager: 517 251 7674
> Livonia, MI 48154-2634 USA Cell: 734 347 3998
>
>
Original Message
> From: Alejandro Vazquez
> [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=-d8iOGOH7mKkCjLJ4wwalP6EBERa4r02ex8_idD1ZWSKfLkO2FiUlsq2Hq64u9fvUjb3NoHHzWRCjs8arCe5]alexvazquez@y...[/url
> Sent: Thursday, March 14, 2002 2:57 PM
> To: basicstamps@yahoogroups.com
> Subject: [noparse][[/noparse]basicstamps] Control 150 leds
>
>
> Hello,
>
> I have a huge problem,,, I have to control with one
> BS2 more than 120 LEDS Independitly. For example I
> want to turn on the last (120) led at the same time
> the first led (1), then I want to turn on all
> leds,,,
> then the odds, then even, etc...etc... I need to
> have
> control of each led independiently.
>
> I have used a 8 bit binary serial driver (from
> allegro
> UCN5821A that I think is similar to the 74HC595
> Shiftregister) but you know I have to use 3 pins of
> the BS2 for clock,data and strobe,,,, so with 16
> pins
> I only have control of 5 5821 with a total of 40
> leds.
>
>
> PLEASE HELP ME!!
> Regards,
> Alejandro Vazque
>
> __________________________________________________
> Do You Yahoo!?
> Yahoo! Sports - live college hoops coverage
> http://sports.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.
>
>
> Your use of Yahoo! Groups is subject to
> http://docs.yahoo.com/info/terms/
>
>
>
> To UNSUBSCRIBE, just send mail to:
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> ignored.
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>
>
__________________________________________________
Do You Yahoo!?
Yahoo! Sports - live college hoops coverage
http://sports.yahoo.com/
>Dear Matt,
>
>Thanks for your help,,,
>I have a question---- the BS2 is a 16 bit micro how
>can I comunicate with a 32 bit device?
>
>Ok so,, I can have control of 160 leds with 5 5833,,,
>independiently but how can I connect in chain multiple
>units,, do I still have control of each led?
>
>
>Thanks for your help
>Alejandro Vazquez
Alejandro -
You can download the UCN5833 data sheet from this link:
http://www.allegromicro.com/sf/5833/index.htm
In the data sheet or on the web page you will see this device accepts SERIAL
INPUT, so the number of "bits" is not significant.
Hope that helps.
Regards,
Bruce Bates
> Dear Matt,
>
> Thanks for your help,,,
> I have a question---- the BS2 is a 16 bit micro how
> can I comunicate with a 32 bit device?
>
The key in his description was that it is a "serially
controlled" device. This means that it sets each of the 32 bits based
upon a serial data stream entering the chip via (most likely) a 3 wire SPI
interface.
g.
--
"I'm not crazy, I'm plausibly off-nominal!"
http://www.f15sim.com - The only one of its kind.
>they can drive 64 LEDs from a 24 pin chip. The National part I'm thinking
>of is a 40 pin package and only drives 33 (or 35, I don't recall
>exactly) LEDs. Are they tieing all the cathodes together or something?
Hurrah !! After months of bugging people for stuff on this list and not
being able to give anything back. Finally I may be able to be of some small
assistance to someone.
This chip works by tying the anodes of all the LEDS together, So for
instance led 1 and led 8 have the same anode but different cathodes. The
cathodes are then scanned while the appropriate data is output to the
anodes. Which means that 64 leds can be driven from a 16 pin's.
Now as long as the LEDS are being viewed by humans there is no problem the
scanning frequency is high enough for them not to notice the scan. Film
cameras are a very different proposition (as are video cameras but for a
different reason). If you intend to film them then you will need to sync
the clock rate of the chips with a separate source. (this is very easy as
long as you are prepared and of course if you need to do this just ask[noparse]:)[/noparse]
Justin Pentecost