looking to build or find inexpensive 3-digit 7-segment LED display

28 Feb 2008 15:20:36

I need to display the numbers 0-255 in decimal on a 3-digit LED
display for a microcontroller project (it would need to be visible in
the dark). Ideally the display would be inexpensive and not take up
too many uC outputs, but what I am finding is expensive ($30 or more).
Does anyone make an inexpensive 3-digit 7-segment LED module that
accepts serial input from say, a PICAXE or a BASIC Stamp 2? Also I
haven't done anything using serial i/o yet but I saw some displays
that had a "clock" pin (so the controller can sync up the data stream
with the module). Would I need to get a clock module for the basic
stamp to talk to the display module? What would a good one be? Can you
build a reliable clock for less using a 555 timer? I as thinking about
how such a device might work without a clock and thought of a way to
do it with 2 lines output, 0-0 would mean no data, 0-1 would mean here
comes some data, 1-0 would mean low, 1-1 would mean high. The display
module would consist of a microcontroller with 2 inputs and 12 outputs
(3 groups of 4 outputs going to a 7-segment encoder IC to drive each
digit). Is this a decent solution or unnecessary? Any advice or links
to a good example would be appreciated... Thanks.

28 Feb 2008 18:35:37

DJ Delorie

Re: looking to build or find inexpensive 3-digit 7-segment LED display

mad.scientist.jr@gmail.com writes:
> Does anyone make an inexpensive 3-digit 7-segment LED module

Is $2 inexpensive enough? (not including the LEDs themselves)

http://www.delorie.com/electronics/bin2seven/

That one is for independent digits and a parallel interface. I've
done a variant that uses common-segments (i.e. seven segment drivers,
three digit drivers) but you need a clock input.

I suppose I could try adding an SPI interface, but I might have to
drop one of the other features to get it to fit.

> how such a device might work without a clock and thought of a way to
> do it with 2 lines output, 0-0 would mean no data, 0-1 would mean here
> comes some data, 1-0 would mean low, 1-1 would mean high.

The way it usually works is: you change the data line to high or low,
then toggle the clock.

> The display module would consist of a microcontroller with 2 inputs
> and 12 outputs (3 groups of 4 outputs going to a 7-segment encoder
> IC to drive each digit). Is this a decent solution or unnecessary?

If you can find a microcontroller cheap enough, sure, it's a great
idea. The uC can probably do the bcd-to-seven decoding for you also,
saving you three chips.

For a uC, you'd need SPI or I2C (two lines), plus seven segment
drivers and three digit drivers, total of 12 I/O pins. I did
something like that with this uC:
http://www.delorie.com/electronics/r8c-27-adapter/

That's more like a $5 solution though.

Of course, if you already have a PIC, you can probably do the decoding
in there, and just output 21 bits to a shift register. Say, three
74164's in series. That's about a $1.80 solution.

28 Feb 2008 15:42:34

Jim Thompson

Re: looking to build or find inexpensive 3-digit 7-segment LED display

<mad.scientist.jr@gmail.com > wrote in message
news:822b2e22-260a-4ed7-ad34-3232bb35e76e@e25g2000prg.googlegroups.com...
>I need to display the numbers 0-255 in decimal on a 3-digit LED
> display for a microcontroller project (it would need to be visible in
> the dark). Ideally the display would be inexpensive and not take up
> too many uC outputs, but what I am finding is expensive ($30 or more).
> Does anyone make an inexpensive 3-digit 7-segment LED module that
> accepts serial input from say, a PICAXE or a BASIC Stamp 2? Also I
> haven't done anything using serial i/o yet but I saw some displays
> that had a "clock" pin (so the controller can sync up the data stream
> with the module). Would I need to get a clock module for the basic
> stamp to talk to the display module? What would a good one be? Can you
> build a reliable clock for less using a 555 timer? I as thinking about
> how such a device might work without a clock and thought of a way to
> do it with 2 lines output, 0-0 would mean no data, 0-1 would mean here
> comes some data, 1-0 would mean low, 1-1 would mean high. The display
> module would consist of a microcontroller with 2 inputs and 12 outputs
> (3 groups of 4 outputs going to a 7-segment encoder IC to drive each
> digit). Is this a decent solution or unnecessary? Any advice or links
> to a good example would be appreciated... Thanks.

Save your cash, forget electronic toys, you will be starved.. Only buy what
you need. Take me for example, I am out of job, I have to post my fancy ad
at the bottom of my post every time. Go figure.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et moi
|
|
| Analog/Mixed-Signal ASICK's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Rat Bastard |
| http://www.analog-innovations.com | 1962 |

America: Land of the Freedom Abusers, Because of the Bastards.

29 Feb 2008 00:48:33

Martin Griffith

Re: looking to build or find inexpensive 3-digit 7-segment LED display

On Thu, 28 Feb 2008 15:20:36 -0800 (PST), in sci.electronics.design
mad.scientist.jr@gmail.com wrote:

>I need to display the numbers 0-255 in decimal on a 3-digit LED
>display for a microcontroller project (it would need to be visible in
>the dark). Ideally the display would be inexpensive and not take up
>too many uC outputs, but what I am finding is expensive ($30 or more).
>Does anyone make an inexpensive 3-digit 7-segment LED module that
>accepts serial input from say, a PICAXE or a BASIC Stamp 2? Also I
>haven't done anything using serial i/o yet but I saw some displays
>that had a "clock" pin (so the controller can sync up the data stream
>with the module). Would I need to get a clock module for the basic
>stamp to talk to the display module? What would a good one be? Can you
>build a reliable clock for less using a 555 timer? I as thinking about
>how such a device might work without a clock and thought of a way to
>do it with 2 lines output, 0-0 would mean no data, 0-1 would mean here
>comes some data, 1-0 would mean low, 1-1 would mean high. The display
>module would consist of a microcontroller with 2 inputs and 12 outputs
>(3 groups of 4 outputs going to a 7-segment encoder IC to drive each
>digit). Is this a decent solution or unnecessary? Any advice or links
>to a good example would be appreciated... Thanks.

Abitof white spacewouldbeappreciatedinanyfollowupsbutyoucouldtry
somethinglikeSTP16C596fromSTmicroHopesthishelps

Kthksbye

martin

28 Feb 2008 16:17:12

linnix

Re: looking to build or find inexpensive 3-digit 7-segment LED

On Feb 28, 3:20 pm, mad.scientist...@gmail.com wrote:
> I need to display the numbers 0-255 in decimal on a 3-digit LED
> display for a microcontroller project (it would need to be visible in
> the dark). Ideally the display would be inexpensive and not take up
> too many uC outputs, but what I am finding is expensive ($30 or more).

Don't know what/where you are looking. Digikey sells some 3 digit
LEDs for $3 to $5 plus another $4 to $5 for the uC. You can do it
below $10.

28 Feb 2008 16:26:25

William Sommerwerck

Re: looking to build or find inexpensive 3-digit 7-segment LED display

"Jim Thompson" wrote in message news:fq7gu2$f6j$2@aioe.org... >
<mad.scientist.jr@gmail.com > wrote in message
> news:822b2e22-260a-4ed7-ad34-3232bb35e76e@e25g2000prg.googlegroups.com...

>> I need to display the numbers 0-255 in decimal on a 3-digit LED
>> display for a microcontroller project (it would need to be visible in
>> the dark). Ideally the display would be inexpensive and not take up
>> too many uC outputs, but what I am finding is expensive ($30 or more).
>> Does anyone make an inexpensive 3-digit 7-segment LED module that
>> accepts serial input from say, a PICAXE or a BASIC Stamp 2? Also I
>> haven't done anything using serial i/o yet but I saw some displays
>> that had a "clock" pin (so the controller can sync up the data stream
>> with the module). Would I need to get a clock module for the basic
>> stamp to talk to the display module? What would a good one be? Can you
>> build a reliable clock for less using a 555 timer? I as thinking about
>> how such a device might work without a clock and thought of a way to
>> do it with 2 lines output, 0-0 would mean no data, 0-1 would mean here
>> comes some data, 1-0 would mean low, 1-1 would mean high. The display
>> module would consist of a microcontroller with 2 inputs and 12 outputs
>> (3 groups of 4 outputs going to a 7-segment encoder IC to drive each
>> digit). Is this a decent solution or unnecessary? Any advice or links
>> to a good example would be appreciated... Thanks.

You sure ask a lot of questions for someone from New Jersey.

> Save your cash, forget electronic toys, you will be starved. Only buy what
> you need. Take me for example, I am out of job, I have to post my fancy ad
> at the bottom of my post every time. Go figure.

> Analog/Mixed-Signal ASICK's and Discrete Systems

Is that a joke?

Why has no one ever pointed out that ASICs are actually AN-SICs?

28 Feb 2008 17:36:02

donald

Re: looking to build or find inexpensive 3-digit 7-segment LED display

linnix wrote:
> On Feb 28, 3:20 pm, mad.scientist...@gmail.com wrote:
>> I need to display the numbers 0-255 in decimal on a 3-digit LED
>> display for a microcontroller project (it would need to be visible in
>> the dark). Ideally the display would be inexpensive and not take up
>> too many uC outputs, but what I am finding is expensive ($30 or more).
>
> Don't know what/where you are looking. Digikey sells some 3 digit
> LEDs for $3 to $5 plus another $4 to $5 for the uC. You can do it
> below $10.
You can buy a hand full of parts for less then $10.

A finished product is another matter.

donald

29 Feb 2008 00:54:33

john jardine

Re: looking to build or find inexpensive 3-digit 7-segment LED display

28 Feb 2008 20:31:03

Robert Baer

Re: looking to build or find inexpensive 3-digit 7-segment LED display

mad.scientist.jr@gmail.com wrote:

> I need to display the numbers 0-255 in decimal on a 3-digit LED
> display for a microcontroller project (it would need to be visible in
> the dark). Ideally the display would be inexpensive and not take up
> too many uC outputs, but what I am finding is expensive ($30 or more).
> Does anyone make an inexpensive 3-digit 7-segment LED module that
> accepts serial input from say, a PICAXE or a BASIC Stamp 2? Also I
> haven't done anything using serial i/o yet but I saw some displays
> that had a "clock" pin (so the controller can sync up the data stream
> with the module). Would I need to get a clock module for the basic
> stamp to talk to the display module? What would a good one be? Can you
> build a reliable clock for less using a 555 timer? I as thinking about
> how such a device might work without a clock and thought of a way to
> do it with 2 lines output, 0-0 would mean no data, 0-1 would mean here
> comes some data, 1-0 would mean low, 1-1 would mean high. The display
> module would consist of a microcontroller with 2 inputs and 12 outputs
> (3 groups of 4 outputs going to a 7-segment encoder IC to drive each
> digit). Is this a decent solution or unnecessary? Any advice or links
> to a good example would be appreciated... Thanks.
Simple...buy a $3-$9 DVOM and rip the display out of it...

28 Feb 2008 21:55:12

mng

Re: looking to build or find inexpensive 3-digit 7-segment LED

Just string up some shift registers. 1 line clock, 1 line data. It
goes fast enough that updating isn't visible to the eye.

28 Feb 2008 22:26:10

MooseFET

Re: looking to build or find inexpensive 3-digit 7-segment LED display

"William Sommerwerck" <grizzledgeezer@comcast.net > wrote in message
news:a76dnQoItejRzFranZ2dnUVZ_ternZ2d@comcast.com...
> "Jim Thompson" wrote in message news:fq7gu2$f6j$2@aioe.org...>
> <mad.scientist.jr@gmail.com> wrote in message
>> news:822b2e22-260a-4ed7-ad34-3232bb35e76e@e25g2000prg.googlegroups.com...
>
>>> I need to display the numbers 0-255 in decimal on a 3-digit LED
>>> display for a microcontroller project (it would need to be visible in
>>> the dark). Ideally the display would be inexpensive and not take up
>>> too many uC outputs, but what I am finding is expensive ($30 or more).
>>> Does anyone make an inexpensive 3-digit 7-segment LED module that
>>> accepts serial input from say, a PICAXE or a BASIC Stamp 2? Also I
>>> haven't done anything using serial i/o yet but I saw some displays
>>> that had a "clock" pin (so the controller can sync up the data stream
>>> with the module). Would I need to get a clock module for the basic
>>> stamp to talk to the display module? What would a good one be? Can you
>>> build a reliable clock for less using a 555 timer? I as thinking about
>>> how such a device might work without a clock and thought of a way to
>>> do it with 2 lines output, 0-0 would mean no data, 0-1 would mean here
>>> comes some data, 1-0 would mean low, 1-1 would mean high. The display
>>> module would consist of a microcontroller with 2 inputs and 12 outputs
>>> (3 groups of 4 outputs going to a 7-segment encoder IC to drive each
>>> digit). Is this a decent solution or unnecessary? Any advice or links
>>> to a good example would be appreciated... Thanks.
>
> You sure ask a lot of questions for someone from New Jersey.
>
>
>> Save your cash, forget electronic toys, you will be starved. Only buy
>> what
>> you need. Take me for example, I am out of job, I have to post my fancy
>> ad
>> at the bottom of my post every time. Go figure.
>
>> Analog/Mixed-Signal ASICK's and Discrete Systems
>
> Is that a joke?
>
> Why has no one ever pointed out that ASICs are actually AN-SICs?
>

Because Jim and I are retarded bastards. Your definition sounds to close to
ANSI C definition. There are million ways to name a thing.

28 Feb 2008 23:31:23

MooseFET

Re: looking to build or find inexpensive 3-digit 7-segment LED display

"Robert Baer" <robertbaer@localnet.com > wrote in message
news:13sf2hoqnd7ku3b@corp.supernews.com...
> mad.scientist.jr@gmail.com wrote:
>
>> I need to display the numbers 0-255 in decimal on a 3-digit LED
>> display for a microcontroller project (it would need to be visible in
>> the dark). Ideally the display would be inexpensive and not take up
>> too many uC outputs, but what I am finding is expensive ($30 or more).
>> Does anyone make an inexpensive 3-digit 7-segment LED module that
>> accepts serial input from say, a PICAXE or a BASIC Stamp 2? Also I
>> haven't done anything using serial i/o yet but I saw some displays
>> that had a "clock" pin (so the controller can sync up the data stream
>> with the module). Would I need to get a clock module for the basic
>> stamp to talk to the display module? What would a good one be? Can you
>> build a reliable clock for less using a 555 timer? I as thinking about
>> how such a device might work without a clock and thought of a way to
>> do it with 2 lines output, 0-0 would mean no data, 0-1 would mean here
>> comes some data, 1-0 would mean low, 1-1 would mean high. The display
>> module would consist of a microcontroller with 2 inputs and 12 outputs
>> (3 groups of 4 outputs going to a 7-segment encoder IC to drive each
>> digit). Is this a decent solution or unnecessary? Any advice or links
>> to a good example would be appreciated... Thanks.
> Simple...buy a $3-$9 DVOM and rip the display out of it...

Good idea pop but..... How are you going to get the 32 pin definition of
your Chinese LED display?

PS. To Jim Thompson, please return my butt plug, quit borrowing my stuffs,
go get your own.

29 Feb 2008 03:27:48

Michael A. Terrell

Re: looking to build or find inexpensive 3-digit 7-segment LED display

William Sommerwerck wrote:
>
> "Jim Thompson" wrote in message news:fq7gu2$f6j$2@aioe.org...>
> <mad.scientist.jr@gmail.com> wrote in message
> > news:822b2e22-260a-4ed7-ad34-3232bb35e76e@e25g2000prg.googlegroups.com...
>
> >> I need to display the numbers 0-255 in decimal on a 3-digit LED
> >> display for a microcontroller project (it would need to be visible in
> >> the dark). Ideally the display would be inexpensive and not take up
> >> too many uC outputs, but what I am finding is expensive ($30 or more).
> >> Does anyone make an inexpensive 3-digit 7-segment LED module that
> >> accepts serial input from say, a PICAXE or a BASIC Stamp 2? Also I
> >> haven't done anything using serial i/o yet but I saw some displays
> >> that had a "clock" pin (so the controller can sync up the data stream
> >> with the module). Would I need to get a clock module for the basic
> >> stamp to talk to the display module? What would a good one be? Can you
> >> build a reliable clock for less using a 555 timer? I as thinking about
> >> how such a device might work without a clock and thought of a way to
> >> do it with 2 lines output, 0-0 would mean no data, 0-1 would mean here
> >> comes some data, 1-0 would mean low, 1-1 would mean high. The display
> >> module would consist of a microcontroller with 2 inputs and 12 outputs
> >> (3 groups of 4 outputs going to a 7-segment encoder IC to drive each
> >> digit). Is this a decent solution or unnecessary? Any advice or links
> >> to a good example would be appreciated... Thanks.
>
> You sure ask a lot of questions for someone from New Jersey.
>
> > Save your cash, forget electronic toys, you will be starved. Only buy what
> > you need. Take me for example, I am out of job, I have to post my fancy ad
> > at the bottom of my post every time. Go figure.
>
> > Analog/Mixed-Signal ASICK's and Discrete Systems
>
> Is that a joke?
>
> Why has no one ever pointed out that ASICs are actually AN-SICs?

Becasue ahe troll forging post as Jim thompson doesn't know what
you're talking about.

Jim post though cox, not aioe.org.

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From:
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<To-Email-Use-The-Envelope-Icon@My-Web-Site.com >
Newsgroups:
sci.electronics.components, sci.electronics.design,
sci.electronics.repair
Subject:
Re: looking to build or find inexpensive 3-digit 7-segment
LED display
Date:
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--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

29 Feb 2008 00:40:09

MooseFET

Re: looking to build or find inexpensive 3-digit 7-segment LED display

"MooseFET" <kensmith@rahul.net > wrote in message
news:fq88io$k14$1@aioe.org...
>
> "William Sommerwerck" <grizzledgeezer@comcast.net> wrote in message
> news:a76dnQoItejRzFranZ2dnUVZ_ternZ2d@comcast.com...
>> "Jim Thompson" wrote in message news:fq7gu2$f6j$2@aioe.org...>
>> <mad.scientist.jr@gmail.com> wrote in message
>>> news:822b2e22-260a-4ed7-ad34-3232bb35e76e@e25g2000prg.googlegroups.com...
>>
>>>> I need to display the numbers 0-255 in decimal on a 3-digit LED
>>>> display for a microcontroller project (it would need to be visible in
>>>> the dark). Ideally the display would be inexpensive and not take up
>>>> too many uC outputs, but what I am finding is expensive ($30 or more).
>>>> Does anyone make an inexpensive 3-digit 7-segment LED module that
>>>> accepts serial input from say, a PICAXE or a BASIC Stamp 2? Also I
>>>> haven't done anything using serial i/o yet but I saw some displays
>>>> that had a "clock" pin (so the controller can sync up the data stream
>>>> with the module). Would I need to get a clock module for the basic
>>>> stamp to talk to the display module? What would a good one be? Can you
>>>> build a reliable clock for less using a 555 timer? I as thinking about
>>>> how such a device might work without a clock and thought of a way to
>>>> do it with 2 lines output, 0-0 would mean no data, 0-1 would mean here
>>>> comes some data, 1-0 would mean low, 1-1 would mean high. The display
>>>> module would consist of a microcontroller with 2 inputs and 12 outputs
>>>> (3 groups of 4 outputs going to a 7-segment encoder IC to drive each
>>>> digit). Is this a decent solution or unnecessary? Any advice or links
>>>> to a good example would be appreciated... Thanks.
>>
>> You sure ask a lot of questions for someone from New Jersey.
>>
>>
>>> Save your cash, forget electronic toys, you will be starved. Only buy
>>> what
>>> you need. Take me for example, I am out of job, I have to post my fancy
>>> ad
>>> at the bottom of my post every time. Go figure.
>>
>>> Analog/Mixed-Signal ASICK's and Discrete Systems
>>
>> Is that a joke?
>>
>> Why has no one ever pointed out that ASICs are actually AN-SICs?
>>
>
>
> Because Jim and I are retarded bastards. Your definition sounds to close
> to
> ANSI C definition. There are million ways to name a thing.
>
>

I forgot to mention Michael A. TerribleIl, he's a super-retarded soldier who
went with the idiots to war, they claimed they did it for Iraq, then claimed
it's for us, then claimed it's for the world. It's funny to no end.

29 Feb 2008 00:48:44

MooseFET

Re: looking to build or find inexpensive 3-digit 7-segment LED display

"mng" <michael.jh.ng@gmail.com > wrote in message
news:afcfb90d-a052-4904-98a9-0b7813bd6607@d4g2000prg.googlegroups.com...
> Just string up some shift registers. 1 line clock, 1 line data. It
> goes fast enough that updating isn't visible to the eye.

He knows that dummy, but he's looking for something cheap cheap....

Why you people always do thing the hard way? from math to Electronic
circuit? Look at your division math, you work too hard. I can do it
visually. No writing whatsoever.

29 Feb 2008 06:30:57

Fred Bloggs

Re: looking to build or find inexpensive 3-digit 7-segment LED display

> I need to display the numbers 0-255 in decimal on a 3-digit LED
> display for a microcontroller project (it would need to be visible in
> the dark). Ideally the display would be inexpensive and not take up
> too many uC outputs, but what I am finding is expensive ($30 or more).
> Does anyone make an inexpensive 3-digit 7-segment LED module that
> accepts serial input from say, a PICAXE or a BASIC Stamp 2? Also I
> haven't done anything using serial i/o yet but I saw some displays
> that had a "clock" pin (so the controller can sync up the data stream
> with the module). Would I need to get a clock module for the basic
> stamp to talk to the display module? What would a good one be? Can you
> build a reliable clock for less using a 555 timer? I as thinking about
> how such a device might work without a clock and thought of a way to
> do it with 2 lines output, 0-0 would mean no data, 0-1 would mean here
> comes some data, 1-0 would mean low, 1-1 would mean high. The display
> module would consist of a microcontroller with 2 inputs and 12 outputs
> (3 groups of 4 outputs going to a 7-segment encoder IC to drive each
> digit). Is this a decent solution or unnecessary? Any advice or links
> to a good example would be appreciated... Thanks.

You can adapt this to three digits, it was intended to be driven by an
8-bit PIC port, is cheap and fast, and uses parts readily available from
Mouser or Digikey:
View in a fixed-width font such as Courier.

.
.
.
.
. RA7=0 ;used to enable write without address error
.
. FOR DIGIT=1 TO 7
.
. RA4-RA6= DIGIT-1
.
. FOR SEGMENT=1 TO 7
.
. RA1-RA3= SEGMENT-1
.
. RA0= SEGMENT ON/OFF (1/0)
.
. OUTPUT RA0-RA7
.
. RA7=1
.
. OUTPUT RA0-RA7
.
. RA7=0
.
. OUTPUT RA0-RA7
.
. NEXT SEGMENT
.
. NEXT DIGIT
.
.
.
.
.
.
.
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. LED DRIVER ---
. --------------- 7 f| g |b
. wherever-----|CLR O1a-O1g|----/---- --- DIGIT1
. | | e| d |c
. | | ---
. RA0-----------------|D | ---
. | | 7 | |
. s | O2a-O2g|----/---- --- DIGIT2
. e RA1-----------------|A0 | | |
. g | | ---
. m RA2-----------------|A1 | ---
. e | | 7 | |
. n RA3-----------------|A2 O3a-O3g|----/---- --- DIGIT3
. t ------ | | | |
. | __| |__ | ---
. d RA4 -----|S0 O1|---|G1 | ---
. i | __| |__ | 7 | |
. g RA5------|S1 O2|---|G2 O4a-O4g|----/---- --- DIGIT4
. i | __| |__ | | |
. t RA6------|S2 O3|---|G3 | ---
. | __| |__ | ---
. | O4|---|G4 | 7 | |
. RA7------|G __| |__ O5a-O5g|----/---- --- DIGIT5
. | O5|---|G5 | | |
. |__ __| |__ | ---
. .--|G1 O6|---|G6 | ---
. | |__ __| |__ | 7 | |
. +--|G2 O7|---|G7 O6a-O6g|----/---- --- DIGIT6
. | ------ | | | |
. --- 74HC138 | | ---
. gnd digit | | ---
. select | | 7 | |
. | O7a-O7g| ---/---- --- DIGIT7
. --------------- | |
. ---
.
.
.
. O1a-O1g O7a-O7g
. LED DRIVER | |
. .-------------------------------------------------------
. | U1 | U7 | |
. | TPIC6B259 | TPIC6B259 | |
. | ------- | 7x TPIC6B259 ------- | |
. D |- > -|D O1a|/| -|D O7a|/| |
. | | | | o o o | | | |
. | |__ O1b|/| |__ O7b|/| |
. | .-----|G1 | | .-----|G7 | | |
. | | | O1c|/| | | O7c|/| |
. --- | | |___ | | | |___ | | |
. CLR |- > | -|CLR O1d|/| | -|CLR O7d|/| |
. | | | | | | | | | |
. | | | O1e|/| | | O7e|/| |
. A0|- > | -|A0 | | | -|A0 | | |
. | | | O1f|/| | | O7f|/| |
. A1|- > | -|A1 | | | -|A1 | | |
. | | | O1g|/ | | O7g|/ |
. A2|- > | -|A2 | | -|A2 | |
. | | | O18|-NC | | O78|-NC |
. | | ------- | ------- |
. __| | DIGIT1 DRIVE | DIGIT7 DRIVE |
. G1|------' 7-segments | 7-segments |
. __| a-g | a-g |
. G2|------ > | |
. __| | |
. G3|---------- > | A2 A1 A0 seg |
. __| | 0 0 0 a |
. G4|------------ > | 0 0 1 b |
. __| | 0 1 0 c |
. G5|-------------- > | 0 1 1 d |
. __| | 1 0 0 e |
. G6|----------------- > | 1 0 1 f |
. __| | 1 1 0 g |
. G7|----------------------------------' |
. -------------------------------------------------------
.

29 Feb 2008 04:05:54

William Sommerwerck

Re: looking to build or find inexpensive 3-digit 7-segment LED display

"MooseFET" <kensmith@rahul.net > wrote in message
news:fq88io$k14$1@aioe.org...
> "William Sommerwerck" <grizzledgeezer@comcast.net> wrote in message
> news:a76dnQoItejRzFranZ2dnUVZ_ternZ2d@comcast.com...

>> Why has no one ever pointed out that ASICs are actually AN-SICs?

> Because Jim and I are retarded bastards. Your definition sounds to
> close to ANSI C definition. There are million ways to name a thing.

What does C have to do with ICs? As usual, one needs to spell out
everything.

An "application-specific IC" is no more an application-specific device than
blank sheets of paper and pile of pencils are a novel. They should actually
be called "application non-specific ICs".

29 Feb 2008 06:29:12

MooseFET

Re: looking to build or find inexpensive 3-digit 7-segment LED

On Feb 29, 12:48 am, "MooseFET" <kensm...@rahul.net > wrote:
> "mng" <michael.jh...@gmail.com> wrote in message
>
> news:afcfb90d-a052-4904-98a9-0b7813bd6607@d4g2000prg.googlegroups.com...
>
> > Just string up some shift registers. 1 line clock, 1 line data. It
> > goes fast enough that updating isn't visible to the eye.
>
> He knows that dummy, but he's looking for something cheap cheap....
>
> Why you people always do thing the hard way? from math to Electronic
> circuit? Look at your division math, you work too hard. I can do it
> visually. No writing whatsoever.

The above was a forged post. The forger appears, based on the
structure, to be a 12-15 year old girl. I wish she'd go find
something more useful to do.

29 Feb 2008 08:53:13

MooseFET

Re: looking to build or find inexpensive 3-digit 7-segment LED display

"William Sommerwerck" <grizzledgeezer@comcast.net > wrote in message
news:2ICdnbCGArGgaFranZ2dnUVZ_u2mnZ2d@comcast.com...
> "MooseFET" <kensmith@rahul.net> wrote in message
> news:fq88io$k14$1@aioe.org...
>> "William Sommerwerck" <grizzledgeezer@comcast.net> wrote in message
>> news:a76dnQoItejRzFranZ2dnUVZ_ternZ2d@comcast.com...
>
>>> Why has no one ever pointed out that ASICs are actually AN-SICs?
>
>> Because Jim and I are retarded bastards. Your definition sounds to
>> close to ANSI C definition. There are million ways to name a thing.
>
> What does C have to do with ICs? As usual, one needs to spell out
> everything.
>
> An "application-specific IC" is no more an application-specific device
> than
> blank sheets of paper and pile of pencils are a novel. They should
> actually
> be called "application non-specific ICs".
>

"A" stands for "application-specific" dummy. No need to make it lenghty.

29 Feb 2008 08:53:50

MooseFET

Re: looking to build or find inexpensive 3-digit 7-segment LED display

"MooseFET" <kensmith@rahul.net > wrote in message
news:d77ada12-7bc3-444d-af75-83dbc158bad6@u10g2000prn.googlegroups.com...
> On Feb 29, 12:48 am, "MooseFET" <kensm...@rahul.net> wrote:
>> "mng" <michael.jh...@gmail.com> wrote in message
>>
>> news:afcfb90d-a052-4904-98a9-0b7813bd6607@d4g2000prg.googlegroups.com...
>>
>> > Just string up some shift registers. 1 line clock, 1 line data. It
>> > goes fast enough that updating isn't visible to the eye.
>>
>> He knows that dummy, but he's looking for something cheap cheap....
>>
>> Why you people always do thing the hard way? from math to Electronic
>> circuit? Look at your division math, you work too hard. I can do it
>> visually. No writing whatsoever.
>
>
> The above was a forged post. The forger appears, based on the
> structure, to be a 12-15 year old girl. I wish she'd go find
> something more useful to do.

Shut up imposter. Get fucked if you have anything better to do.

29 Feb 2008 10:35:22

William Sommerwerck

Re: looking to build or find inexpensive 3-digit 7-segment LED display

"MooseFET" <kensmith@rahul.net > wrote in message
news:fq9daf$kra$1@aioe.org...
>
> "William Sommerwerck" <grizzledgeezer@comcast.net> wrote in message
> news:2ICdnbCGArGgaFranZ2dnUVZ_u2mnZ2d@comcast.com...
> > "MooseFET" <kensmith@rahul.net> wrote in message
> > news:fq88io$k14$1@aioe.org...
> >> "William Sommerwerck" <grizzledgeezer@comcast.net> wrote in message
> >> news:a76dnQoItejRzFranZ2dnUVZ_ternZ2d@comcast.com...
> >
> >>> Why has no one ever pointed out that ASICs are actually AN-SICs?
> >
> >> Because Jim and I are retarded bastards. Your definition sounds to
> >> close to ANSI C definition. There are million ways to name a thing.
> >
> > What does C have to do with ICs? As usual, one needs to spell out
> > everything.
> >
> > An "application-specific IC" is no more an application-specific device
> > than
> > blank sheets of paper and pile of pencils are a novel. They should
> > actually
> > be called "application non-specific ICs".
> >
>
>
> "A" stands for "application-specific" dummy. No need to make it lenghty.

Again, you miss the point.

01 Mar 2008 09:51:45

John Fields

Re: looking to build or find inexpensive 3-digit 7-segment LED display

On Thu, 28 Feb 2008 15:20:36 -0800 (PST), mad.scientist.jr@gmail.com
wrote:

>I need to display the numbers 0-255 in decimal on a 3-digit LED
>display for a microcontroller project (it would need to be visible in
>the dark). Ideally the display would be inexpensive and not take up
>too many uC outputs, but what I am finding is expensive ($30 or more).
>Does anyone make an inexpensive 3-digit 7-segment LED module that
>accepts serial input from say, a PICAXE or a BASIC Stamp 2? Also I
>haven't done anything using serial i/o yet but I saw some displays
>that had a "clock" pin (so the controller can sync up the data stream
>with the module). Would I need to get a clock module for the basic
>stamp to talk to the display module? What would a good one be? Can you
>build a reliable clock for less using a 555 timer? I as thinking about
>how such a device might work without a clock and thought of a way to
>do it with 2 lines output, 0-0 would mean no data, 0-1 would mean here
>comes some data, 1-0 would mean low, 1-1 would mean high. The display
>module would consist of a microcontroller with 2 inputs and 12 outputs
>(3 groups of 4 outputs going to a 7-segment encoder IC to drive each
>digit). Is this a decent solution or unnecessary? Any advice or links
>to a good example would be appreciated... Thanks.

---
http://www.allegromicro.com/en/Products/Part_Numbers/6275/6275.pdf

http://www.allegromicro.com/en/Products/Part_Numbers/6276/6276.pdf

--
JF

01 Mar 2008 18:23:30

JosephKK

Re: looking to build or find inexpensive 3-digit 7-segment LED display

William Sommerwerck wrote:
> "Jim Thompson" wrote in message news:fq7gu2$f6j$2@aioe.org...>
> <mad.scientist.jr@gmail.com> wrote in message
>> news:822b2e22-260a-4ed7-ad34-3232bb35e76e@e25g2000prg.googlegroups.com...
>
>>> I need to display the numbers 0-255 in decimal on a 3-digit LED
>>> display for a microcontroller project (it would need to be visible in
>>> the dark). Ideally the display would be inexpensive and not take up
>>> too many uC outputs, but what I am finding is expensive ($30 or more).
>>> Does anyone make an inexpensive 3-digit 7-segment LED module that
>>> accepts serial input from say, a PICAXE or a BASIC Stamp 2? Also I
>>> haven't done anything using serial i/o yet but I saw some displays
>>> that had a "clock" pin (so the controller can sync up the data stream
>>> with the module). Would I need to get a clock module for the basic
>>> stamp to talk to the display module? What would a good one be? Can you
>>> build a reliable clock for less using a 555 timer? I as thinking about
>>> how such a device might work without a clock and thought of a way to
>>> do it with 2 lines output, 0-0 would mean no data, 0-1 would mean here
>>> comes some data, 1-0 would mean low, 1-1 would mean high. The display
>>> module would consist of a microcontroller with 2 inputs and 12 outputs
>>> (3 groups of 4 outputs going to a 7-segment encoder IC to drive each
>>> digit). Is this a decent solution or unnecessary? Any advice or links
>>> to a good example would be appreciated... Thanks.
>
> You sure ask a lot of questions for someone from New Jersey.
>
>
>> Save your cash, forget electronic toys, you will be starved. Only buy what
>> you need. Take me for example, I am out of job, I have to post my fancy ad
>> at the bottom of my post every time. Go figure.
>
>> Analog/Mixed-Signal ASICK's and Discrete Systems
>
> Is that a joke?
>
> Why has no one ever pointed out that ASICs are actually AN-SICs?
>
>

Responding to some name faking twit i see. Check the headers.

01 Mar 2008 18:25:51

JosephKK

Re: looking to build or find inexpensive 3-digit 7-segment LED display

William Sommerwerck wrote:
> "MooseFET" <kensmith@rahul.net> wrote in message
> news:fq88io$k14$1@aioe.org...
>> "William Sommerwerck" <grizzledgeezer@comcast.net> wrote in message
>> news:a76dnQoItejRzFranZ2dnUVZ_ternZ2d@comcast.com...
>
>>> Why has no one ever pointed out that ASICs are actually AN-SICs?
>
>> Because Jim and I are retarded bastards. Your definition sounds to
>> close to ANSI C definition. There are million ways to name a thing.
>
> What does C have to do with ICs? As usual, one needs to spell out
> everything.
>
> An "application-specific IC" is no more an application-specific device than
> blank sheets of paper and pile of pencils are a novel. They should actually
> be called "application non-specific ICs".
>
>

Talking up the to the sewer rat still? Check some more headers.

01 Mar 2008 18:52:04

JosephKK

Re: looking to build or find inexpensive 3-digit 7-segment LED display

MooseFET wrote:
> "MooseFET" <kensmith@rahul.net> wrote in message
> news:d77ada12-7bc3-444d-af75-83dbc158bad6@u10g2000prn.googlegroups.com...
>> On Feb 29, 12:48 am, "MooseFET" <kensm...@rahul.net> wrote:
>>> "mng" <michael.jh...@gmail.com> wrote in message
>>>
>>> news:afcfb90d-a052-4904-98a9-0b7813bd6607@d4g2000prg.googlegroups.com...
>>>
>>>> Just string up some shift registers. 1 line clock, 1 line data. It
>>>> goes fast enough that updating isn't visible to the eye.
>>> He knows that dummy, but he's looking for something cheap cheap....
>>>
>>> Why you people always do thing the hard way? from math to Electronic
>>> circuit? Look at your division math, you work too hard. I can do it
>>> visually. No writing whatsoever.
>>
>> The above was a forged post. The forger appears, based on the
>> structure, to be a 12-15 year old girl. I wish she'd go find
>> something more useful to do.
>
>
>
> Shut up imposter. Get fucked if you have anything better to do.
>
>
>
>

Yo impostor/forger if you have a vagina i will do ya.