In comp.arch.embedded,
Mel <mwilson@the-wire.com> wrote:
>
> Alas, the hardware people didn't leave me any test points. Running that
> test would have me playing drums and pressing front-panel buttons with
> several hands while holding a scope probe point on an MCU pin with another.
> Life is never easy.
Life can get a bit easier with some micro test clips, frees up at least one
hand. I have some from pomona that claim to be usable down to 0.3mm pitch
ICs. I have used those without problems on 0.5mm pitch, no experience with
0.3mm. One drawback, they ar not cheap but it saves you soldering test
wires to your micro which takes a lot of time and has a hazard of damaging
things.
--
Stef (remove caps, dashes and .invalid from e-mail address to reply by mail)
General notions are generally wrong.
-- Lady M.W. Montagu
Reply by Paul E Bennett●October 25, 20092009-10-25
Mel wrote:
> Paul E Bennett wrote:
>> Firstly, you didn't say which LCD module and EEPROM. Doing so might have
>> got a wider response already.
>
> I hate to damn a manufacturer with problems that are probably my own --
> see below.
I am sure no-one would have seen it as damning a manufacturer and one could
always add the phrase "probably my own stupidity..." within the mention.
>> Secondly, Logic Analysers are expensive to own and hire so doing the job
>> without is really a very worthwhile skill that more should learn to
>> cultivate.
>
> Funny you should say that. After my subconscious got serious about the
> problem, and I posted my request, I woke up in the night realizing that I
> was clocking the TWI interface too quickly for the LCD. This seems to
> have been true, and bringing the baud rate down to 100KHz has made the
> board beautifully stable.
So you have a visions of a solution then?
>> If these are serial devices I would expect to see the traces on a scope
>> easily enough. Have you got one that can capture a segment of data from
>> pre- trigger point to post-trigger point (Fluke and Tektronix both do a
>> suitable type). Such a scope will allow you to scroll back through the
>> problem zone to see what was happening in detail.
>
> The thing I have is a USB scope pod. It would be worth a try to drag the
> trigger point way over to the right and see if that left me with the last
> available traces. Since the problem involved intermittently locking up
> the U.I. loop, and ceasing to send or receive anything from the module,
> that ought to leave the smoking gun traces in plain view.
>
>> Also learn to instrument the code (toggle a pin with the idle task or
>> something) so that you can pick up points of failure.
>
> Alas, the hardware people didn't leave me any test points. Running that
> test would have me playing drums and pressing front-panel buttons with
> several hands while holding a scope probe point on an MCU pin with
> another. Life is never easy.
I suppose I am spoilt in that respect as I either select, build or specify
exactly what hardware and software will be put into the systems. I love
having suitable test points to monitor what is going on.
--
********************************************************************
Paul E. Bennett...............<email://Paul_E.Bennett@topmail.co.uk>
Forth based HIDECS Consultancy
Mob: +44 (0)7811-639972
Tel: +44 (0)1235-510979
Going Forth Safely ..... EBA. www.electric-boat-association.org.uk..
********************************************************************
Reply by Mel●October 24, 20092009-10-24
Paul E Bennett wrote:
> Firstly, you didn't say which LCD module and EEPROM. Doing so might have
> got a wider response already.
I hate to damn a manufacturer with problems that are probably my own -- see
below.
> Secondly, Logic Analysers are expensive to own and hire so doing the job
> without is really a very worthwhile skill that more should learn to
> cultivate.
Funny you should say that. After my subconscious got serious about the
problem, and I posted my request, I woke up in the night realizing that I
was clocking the TWI interface too quickly for the LCD. This seems to be
have been true, and bringing the baud rate down to 100KHz has made the board
beautifully stable.
> If these are serial devices I would expect to see the traces on a scope
> easily enough. Have you got one that can capture a segment of data from
> pre- trigger point to post-trigger point (Fluke and Tektronix both do a
> suitable type). Such a scope will allow you to scroll back through the
> problem zone to see what was happening in detail.
The thing I have is a USB scope pod. It would be worth a try to drag the
trigger point way over to the right and see if that left me with the last
available traces. Since the problem involved intermittently locking up the
U.I. loop, and ceasing to send or receive anything from the module, that
ought to leave the smoking gun traces in plain view.
> Also learn to instrument the code (toggle a pin with the idle task or
> something) so that you can pick up points of failure.
Alas, the hardware people didn't leave me any test points. Running that
test would have me playing drums and pressing front-panel buttons with
several hands while holding a scope probe point on an MCU pin with another.
Life is never easy.
Mel.
Reply by Neil●October 24, 20092009-10-24
Mel wrote:
> I'm having trouble with an EEPROM and an LCD module hooked to an
> AT91SAM7S256. Software is using the at91lib TWI_* routines that came with
> an evaluation kit. The program seems to be hanging up on incomplete I/O
> with the LCD module, but I don't know why. Analyzing the TWI (aka I2C)
> protocol would either nail the problem or assure me that there was nothing
> to see there.
>
> Where could I get the use of an analyzer?
>
> Thanks, Mel.
>
You could also get n I2C Monitor.
MCC-US.com
Or
www.totalphase.com
Reply by rickman●October 23, 20092009-10-23
On Oct 22, 4:03=A0pm, Rich Webb <bbew...@mapson.nozirev.ten> wrote:
> On Thu, 22 Oct 2009 10:57:24 -0700 (PDT), rickman <gnu...@gmail.com>
> wrote:
>
>
>
> >On Oct 22, 11:19=A0am, "Not Really Me"
> ><sc...@validatedQWERTYsoftware.XYZZY.com> wrote:
> >> Mel wrote:
> >> > I'm having trouble with an EEPROM and an LCD module hooked to an
> >> > AT91SAM7S256. =A0Software is using the at91lib TWI_* routines that c=
ame
> >> > with
> >> > an evaluation kit. =A0The program seems to be hanging up on incomple=
te
> >> > I/O
> >> > with the LCD module, but I don't know why. =A0Analyzing the TWI (aka
> >> > I2C)
> >> > protocol would either nail the problem or assure me that there was
> >> > nothing
> >> > to see there.
>
> >> > Where could I get the use of an analyzer?
>
> >> > Thanks, Mel.
>
> >> Yikes, buy, don't rent. =A0We have a DigiView from Tech-Tools that we =
>
> >I don't have this unit myself, but one of my customers uses it and has
> >more than one.
>
> >http://www.pctestinstruments.com/
>
> >It seemed to work pretty well to me. =A0$389
>
> That's my normal LA, also. Lives in the laptop bag so it's always handy.
I only wish they had drivers for Linux. I'm not using Linux now, but
I don't want to invest in more things that will make a switch hard.
Rick
Reply by Rich Webb●October 22, 20092009-10-22
On Thu, 22 Oct 2009 10:57:24 -0700 (PDT), rickman <gnuarm@gmail.com>
wrote:
>On Oct 22, 11:19�am, "Not Really Me"
><sc...@validatedQWERTYsoftware.XYZZY.com> wrote:
>> Mel wrote:
>> > I'm having trouble with an EEPROM and an LCD module hooked to an
>> > AT91SAM7S256. �Software is using the at91lib TWI_* routines that came
>> > with
>> > an evaluation kit. �The program seems to be hanging up on incomplete
>> > I/O
>> > with the LCD module, but I don't know why. �Analyzing the TWI (aka
>> > I2C)
>> > protocol would either nail the problem or assure me that there was
>> > nothing
>> > to see there.
>>
>> > Where could I get the use of an analyzer?
>>
>> > Thanks, Mel.
>>
>> Yikes, buy, don't rent. �We have a DigiView from Tech-Tools that we love.
>> $500 athttp://www.tech-tools.com/dv_main.htm.
>>
>> This is phenominal logic analyzer. �Does data interpretation and lots more.
>
>I don't have this unit myself, but one of my customers uses it and has
>more than one.
>
>http://www.pctestinstruments.com/
>
>It seemed to work pretty well to me. $389
That's my normal LA, also. Lives in the laptop bag so it's always handy.
--
Rich Webb Norfolk, VA
Reply by rickman●October 22, 20092009-10-22
On Oct 22, 11:19=A0am, "Not Really Me"
<sc...@validatedQWERTYsoftware.XYZZY.com> wrote:
> Mel wrote:
> > I'm having trouble with an EEPROM and an LCD module hooked to an
> > AT91SAM7S256. =A0Software is using the at91lib TWI_* routines that came
> > with
> > an evaluation kit. =A0The program seems to be hanging up on incomplete
> > I/O
> > with the LCD module, but I don't know why. =A0Analyzing the TWI (aka
> > I2C)
> > protocol would either nail the problem or assure me that there was
> > nothing
> > to see there.
>
> > Where could I get the use of an analyzer?
>
> > Thanks, Mel.
>
> Yikes, buy, don't rent. =A0We have a DigiView from Tech-Tools that we lov=
ore.
I don't have this unit myself, but one of my customers uses it and has
more than one.
http://www.pctestinstruments.com/
It seemed to work pretty well to me. $389
Rick
Reply by Not Really Me●October 22, 20092009-10-22
Mel wrote:
> I'm having trouble with an EEPROM and an LCD module hooked to an
> AT91SAM7S256. Software is using the at91lib TWI_* routines that came
> with
> an evaluation kit. The program seems to be hanging up on incomplete
> I/O
> with the LCD module, but I don't know why. Analyzing the TWI (aka
> I2C)
> protocol would either nail the problem or assure me that there was
> nothing
> to see there.
>
> Where could I get the use of an analyzer?
>
> Thanks, Mel.
>
Yikes, buy, don't rent. We have a DigiView from Tech-Tools that we love.
$500 at http://www.tech-tools.com/dv_main.htm.
This is phenominal logic analyzer. Does data interpretation and lots more.
--
Scott
Validated Software
Lafayette, CO
__________ Information from ESET NOD32 Antivirus, version of virus signature database 4533 (20091022) __________
The message was checked by ESET NOD32 Antivirus.
http://www.eset.com
Reply by ChrisQ●October 21, 20092009-10-21
Mel wrote:
> I'm having trouble with an EEPROM and an LCD module hooked to an
> AT91SAM7S256. Software is using the at91lib TWI_* routines that came with
> an evaluation kit. The program seems to be hanging up on incomplete I/O
> with the LCD module, but I don't know why. Analyzing the TWI (aka I2C)
> protocol would either nail the problem or assure me that there was nothing
> to see there.
>
> Where could I get the use of an analyzer?
>
> Thanks, Mel.
>
On the basis that you'll almost definately need it again, renting is a
bad investment and just dead money. You could buy a good used la on ebay
for a fraction of what it would cost you to rent for a month, or even
from a dealer.
Depending on speed requiremnts, an HP 16xx series might be enough, or
better still, one of the system type HP16500 or 16700 series. The latter
were 25 to 50k $ new and more or less last forever...
regards,
Chris
Reply by rickman●October 21, 20092009-10-21
I've been looking for a good oscilloscope front end for a PC, but I
haven't found anything I think is worth the price. There are a few
units that can do both scope and logic analyzer which would be ideal
for me, two channels of analog and 16 to 32 channels of digital. Can
anyone recommend something in this line?
Rick
On Oct 19, 4:42=A0pm, Mel <mwil...@the-wire.com> wrote:
> I'm having trouble with an EEPROM and an LCD module hooked to an
> AT91SAM7S256. =A0Software is using the at91lib TWI_* routines that came w=
ith
> an evaluation kit. =A0The program seems to be hanging up on incomplete I/=
O
> with the LCD module, but I don't know why. =A0Analyzing the TWI (aka I2C)
> protocol would either nail the problem or assure me that there was nothin=
g
> to see there.
>
> Where could I get the use of an analyzer?
>
> =A0 =A0 =A0 =A0 Thanks, =A0 =A0 =A0 =A0 Mel.