Searching \ for '[EE] Digital arbitrary waveform generator?' in subject line. ()
Make payments with PayPal - it's fast, free and secure! Help us get a faster server
FAQ page: www.piclist.com/techref/index.htm?key=digital+arbitrary
Search entire site for: 'Digital arbitrary waveform generator?'.

Exact match. Not showing close matches.
PICList Thread
'[EE] Digital arbitrary waveform generator?'
2008\11\09@161308 by PicDude

flavicon
face

I'm writing code to interpret a signal (custom protocol from another
product), and I need to generate some different *digital* signal streams for
testing.  Frequency on this signal is under 10khz.

All the AWGs I can find are analog, and though I can use them to generate
digital data, I'd like to find something simpler, quicker, and lower-cost
for now.

Yes, I can do this with a PIC, but I don't need another project on my plate
right now.  Anyone here knows of a commercial digital AWG at a relatively
low cost, or perhaps a similar PIC project someone else has done before that
may be floating around on the internet?

Thanks,
-Neil.

--
View this message in context: www.nabble.com/-EE--Digital-arbitrary-waveform-generator--tp20410906p20410906.html
Sent from the PIC - [EE] mailing list archive at Nabble.com.

2008\11\09@164629 by Philip Pemberton

face
flavicon
face
PicDude wrote:
> I'm writing code to interpret a signal (custom protocol from another
> product), and I need to generate some different *digital* signal streams for
> testing.  Frequency on this signal is under 10khz.
>
> All the AWGs I can find are analog, and though I can use them to generate
> digital data, I'd like to find something simpler, quicker, and lower-cost
> for now.

Sounds like what you're after is a digital signal generator (aka word
generator, digital stimulus generator).

I wouldn't expect it to be anywhere near cheap though...

> Yes, I can do this with a PIC, but I don't need another project on my plate
> right now.  Anyone here knows of a commercial digital AWG at a relatively
> low cost, or perhaps a similar PIC project someone else has done before that
> may be floating around on the internet?

You don't even need a PIC.. a 4040 counter, an EPROM and a 555 timer (or other
similar clock source) should be plenty. Use the 555 to generate the output
clock, use that to clock the 4040, then wire the 4040's Q outputs to the
EPROM's address inputs. Wire /CS and /OE (on the EPROM) to ground, then take
your signal output from the EPROM's data outputs.

You're talking about ~1hr of work, excluding programming the EPROM with your
test pattern.

--
Phil.
spam_OUTpiclistTakeThisOuTspamphilpem.me.uk
http://www.philpem.me.uk/

2008\11\09@175915 by PicDude

flavicon
face

Your keywords are getting me much more hits, and "digital pattern generator"
seems to be a popular term for these also.  But you're correct -- pricing is
high, and probably because the specs on those devices are way more than I
need.

Problem with your EEPROM circuit is that I don't have any of those parts
here anymore, as I recently donated a bunch of TTL parts, EPROMs, and even
555's to a local high school.  And I haven't owned an EPROM programmer in
ages.  I have many many PICs though, so I thought I'd have my function
generator clock the PIC (so I can easily get my odd, but fairly tight 0.5%
tolerance frequency), then pull the output stream from a pre-programmed
table.  I can generate the pattern I need with 288 steps, each about 160-ish
microseconds apart, so I don't even need external memory.

I was just hoping someone had done this before and had quietly posted the
code in some corner of the internet.  But I might have to bite the bullet
and write the code tomorrow.

Cheers,
-Neil.




Philip Pemberton-2 wrote:
{Quote hidden}

> --

2008\11\09@215000 by Jinx

face picon face
> And I haven't owned an EPROM programmer in ages

Neil, a long time ago I made an EPROM programmer based on a Motorola
68HC micro. At the time I had to because the programmer I did have couldn't
do the big 4Mb ones which needed to be used. It's reasonably trivial. Basically
loading data and flicking the various control lines of the EPROM - Vpp, /CE,
/WE, /CS etc, as well as clocking a couple of 4040 address drivers. EPROMs
can still be found on discarded PCBs

I just had it on my mind as that old project might be ressurected shortly in a
more modern 21st Century guise so I'd been digging out my notes

2008\11\10@015744 by Ruben Jönsson

flavicon
face
>
> I'm writing code to interpret a signal (custom protocol from another
> product), and I need to generate some different *digital* signal streams for
> testing.  Frequency on this signal is under 10khz.
>
> All the AWGs I can find are analog, and though I can use them to generate
> digital data, I'd like to find something simpler, quicker, and lower-cost
> for now.
>
> Yes, I can do this with a PIC, but I don't need another project on my plate
> right now.  Anyone here knows of a commercial digital AWG at a relatively low
> cost, or perhaps a similar PIC project someone else has done before that may be
> floating around on the internet?
>
> Thanks,
> -Neil.
>
How about using a PC and the sound card. Yes, it is analog, but you might be
able to produce an output that looks digital by creating an appropriate WAV
file. Run this through an appropriate amplifier and a digital buffer that will
give you the right digital levels.

If you don't find an appropriate software that does what you want, perhaps
rolling your own using the parallel port instead of the sound card might be
easier. The digital output train could be configured with a textfile.

/Ruben

==============================
Ruben Jönsson
AB Liros Electronic
Box 9124, 200 39 Malmö, Sweden
TEL INT +46 40142078
FAX INT +46 40947388
rubenspamKILLspampp.sbbs.se
==============================

2008\11\10@083409 by John Coppens

flavicon
face
On Mon, 10 Nov 2008 07:57:40 +0100
"Ruben Jönsson" <.....rubenKILLspamspam.....pp.sbbs.se> wrote:

> How about using a PC and the sound card. Yes, it is analog, but you
> might be able to produce an output that looks digital by creating an
> appropriate WAV file. Run this through an appropriate amplifier and a
> digital buffer that will give you the right digital levels.

... and don't forget the old parallel port! Though it's not easy to get a
good timing, it _is_ easy to use, up to a couple of 100 kHz.

John

2008\11\10@115900 by PicDude

flavicon
face


I actually found a program yesterday that would apparently do that (
http://heliso.tripod.com/download/generator/dsg.htm ), but it looked like it
would take me longer to set it up and create a wav file to time it properly,
vs just writing it in a PIC.  I can't play with this today, so I'll get back
to it in a couple days.




Ruben Jönsson wrote:
{Quote hidden}

> -

2008\11\10@120027 by PicDude

flavicon
face

Actually I did forget the old parallel port.  Linux and C should make this
really quick and simple.
Cheers,
-Neil.




John Coppens wrote:
>
> ...
> ... and don't forget the old parallel port! Though it's not easy to get a
> good timing, it _is_ easy to use, up to a couple of 100 kHz.
>
> John
>
>

--
View this message in context: www.nabble.com/-EE--Digital-arbitrary-waveform-generator--tp20410906p20423838.html
Sent from the PIC - [EE] mailing list archive at Nabble.com.

2008\11\10@122631 by Martin

face
flavicon
face
PicDude wrote:
> Actually I did forget the old parallel port.  Linux and C should make this
> really quick and simple.
> Cheers,
> -Neil.
>

I've actually just done this in Windows XP if you need advice.

-
Martin

2008\11\11@133936 by Vasile Surducan

face picon face
This program :
http://www.qsl.net/dl4yhf/spectra1.html
has a real smart frequency generator.  It's the best free spectrum
analyser combined with a signal generator I've seen.
The author seems to be a very good programmer which has more passion
than any wish of earning money...

Vasile


On 11/10/08, Martin <martinspamspam_OUTnnytech.net> wrote:
{Quote hidden}

> -

2008\11\14@145925 by PicDude

flavicon
face

I usually prefer Linux for this type of stuff, especially since I don't have
to purchase any development tools (I use gcc, etc).   But here, I ended up
creating it with a PIC.  Thanks though.

Cheers,
-Neil.



Martin Klingensmith wrote:
>
>
> I've actually just done this in Windows XP if you need advice.
>
> -
> Martin
> --

More... (looser matching)
- Last day of these posts
- In 2008 , 2009 only
- Today
- New search...