kent@swrinde.nde.swri.edu (Kent D. Polk) (06/23/89)
Please excuse if this article is not appropriate, but does anyone have
experience with using Amigas for fast real-time data acquisition/
control? (As opposed to slow data logging or typically slow process
control).
We (I) build computerized inspection systems for non-destructive
testing, and usually put together our own STD or VME bus systems (black
boxes with custom electronics) which then talk to something with an
operating system (Sun or HP). High-end systems for the power generation
industry usually consist of many '020/'030 slave processors firing data
at a Sun 4 as fast as it can take it. (Can you say "Drinking from a
fire hydrant?) Fortunately, we also build small systems too.
There has been much pressure to get us to use PC's for the whole
system, & so have given in a couple of times, however the results were
dismal - usually ended up disabling most interrupts (clock, keyboard in
particular) that were not needed, & usually have to write our own
custom drivers for things like GPIB, serial, keyboard; such as the
custom driver I wrote for the National Instruments card when run on a
PC - NI's software is way too slow, and the card has a tendency to drop
bytes.
The major obstacles in implementing real-time data acquisition on a PC
are the lack of multitasking (especially involving disk operations
which take forever & lock the machine until done) and the inadequate
bus design. I have encountered problems using faster PCs (12 MHz ATs)
reading I/O ports at a pretty good clip - it seems I have to wait for
the bus to settle down a bit after a read or I'll get garbage (Tech
manual for IBM ATs even mentions this when using assembler). Also, the
design of the board has a lot to do with this problem.
A couple of us have often entertained the though of implementing such
low-cost systems on an Amiga and now have several opportunities to do
so. The main reasons are for it's fast multitasking abilities which
would solve many of the problems we have with PCs and it's graphics
capabilities.
Although I have an A2500 on order, I am looking fo info to determine
its reliability, usefulness, etc. for light industrial operation and am
concerned about it's appropriateness.
Q: Is the A2000 is robust enough (maybe a rackmount version) for such
use?
Q: Has anyone experienced bus read problems (similar to the bus read
garbage on PC's) on the Amiga? Can one recover from a bus error?
We use GPIB devices quite often, usually configured with only 1 or 2
listeners, so setup is quite easy. However we need FAST transfer speeds
and FAST bus setup times. When DMA is not used, most transfers are
small, but bus setup time & small block transfer rate needs to be
optimized and these type of operations bring the National Instruments
PC GPIB board to its knees. This is where I have to write my own
custom drivers.
Q: Does anyone have such info relating to the ASDG GPIB board & it's
operation on the Amiga with respect to the type of operations I just
described?
Q: ASDG TwinX boards: Since I haven't tried to access custom hardware
the system, does ASDG provide software to access TwinX modules? Can
one purchase driver source code?
Q: Does ASDG buffer any of their modules/provide memory mapping for
fast access? (This is one place that a multitasking driver could be a
godsend). I usually have to wait for an event & then grab stuff from
lots of different inputs (position/velocity/instrumentation values)
over GPIB, digital I/O & A/D inputs. On our black boxes we always try
to use memory mapped architecture so this can be done quickly. (Try to
do this fast on an Intel chip - Ha!)
Q: What modes of access to the PC bus are available from the Amiga
side? Do I have to involve the 80xx.x in the process, or can I read the
AT bus directly?
Please forgive if these requests are not appropriate, or if there
are too many questions.
Thank you very much,
"Too many notes" Polk :^)
=======================================================
Kent Polk - Southwest Research Institute
{cs.utexas.edu, gatech!petro sun!texsun}!swrinde!kent
kent@swrinde.nde.swri.edu
-------------------------------------------------------
"Anything worth doing is worth overdoing"
=======================================================balzer@frambo.dec.com (Christian Balzer) (06/27/89)
[Line-eaters, myth or fact? News at 11:00] In article <17668@swrinde.nde.swri.edu>, kent@swrinde.nde.swri.edu (Kent D. Polk) makes my heart jump with joy due to the 2nd "Real Life" Amiga application announcement in two weeks: [lotsa stuff deleted] >Although I have an A2500 on order, I am looking fo info to determine >its reliability, usefulness, etc. for light industrial operation and am >concerned about it's appropriateness. > >Q: Is the A2000 is robust enough (maybe a rackmount version) for such >use? Having banged around my system alot, sometimes during HD access, I would certainly clear the Amiga for "light industrial operation". Make sure you use high quality HD's and don't forget to tighten those screws. I forgot that once... :-} >Q: Has anyone experienced bus read problems (similar to the bus read >garbage on PC's) on the Amiga? Can one recover from a bus error? No, but I (or SW/HW in my system) probably never pushed into the regions you're headed. (Going baldly, erh boldly where noone has gone before :-) >We use GPIB devices quite often, usually configured with only 1 or 2 >listeners, so setup is quite easy. However we need FAST transfer speeds >and FAST bus setup times. When DMA is not used, most transfers are >small, but bus setup time & small block transfer rate needs to be >optimized and these type of operations bring the National Instruments >PC GPIB board to its knees. This is where I have to write my own >custom drivers. > >Q: Does anyone have such info relating to the ASDG GPIB board & it's >operation on the Amiga with respect to the type of operations I just >described? To my greatest surprise I do have such info. The ASDG TwinX/GPIB board will NOT support DMA. However you can have the DMA request trigger an interrupt. >Q: ASDG TwinX boards: Since I haven't tried to access custom hardware >the system, does ASDG provide software to access TwinX modules? Can >one purchase driver source code? Dunno, you might wanna ask Aaron Avery (aaron@madnix.UUCP) or even Perry K. himself. ASDG sells you a driver (GPIB.library) with the stuff, though. >Q: Does ASDG buffer any of their modules/provide memory mapping for >fast access? (This is one place that a multitasking driver could be a >godsend). I usually have to wait for an event & then grab stuff from >lots of different inputs (position/velocity/instrumentation values) >over GPIB, digital I/O & A/D inputs. On our black boxes we always try >to use memory mapped architecture so this can be done quickly. (Try to >do this fast on an Intel chip - Ha!) Dunno (see above), but from my documentation this doesn't seem to be the case. They do support 8 or 16 bit modules, though. >Q: What modes of access to the PC bus are available from the Amiga >side? Do I have to involve the 80xx.x in the process, or can I read the >AT bus directly? Nope, the AT bus only shares the power with the rest of the Amiga. You must either use a CBM Bridgeboard or wait for that dumb but fast and cheap connection bridge that was proposed here some months ago. But with your knowledge and resources a "dumb" bridge should be nooo problem. (Thus spoke the softhead and quickly fleed. :-) >======================================================= > Kent Polk - Southwest Research Institute > {cs.utexas.edu, gatech!petro sun!texsun}!swrinde!kent > kent@swrinde.nde.swri.edu >------------------------------------------------------- > "Anything worth doing is worth overdoing" >======================================================= Ya betcha! :-) BTW, I already answered some of Kent's questions in a related posting to c.s.a last week. But that was eaten by our @#!?%& mailer! Hope that helps, - <CB> -- _ _ / / | \ \ <CB> aka Christian Balzer - The Software Brewery - < < |-< > EMail: ...!decwrl!frambo.dec.com!CB -OR- CB@frambo.dec.com \ \_ |_/ / E-Net: FRAMBO::BALZER | Home-Phone: +49 6150 4151 (CET!) ------------ PMail: Im Wingertsberg 45, D-6108 Weiterstadt, F.R.G.
kent@swrinde.nde.swri.edu (Kent D. Polk) (06/29/89)
In article <3182@shlump.dec.com> balzer@frambo.dec.com (Christian Balzer) writes: >>(Q: about ASDG GPIB Board by me) >To my greatest surprise I do have such info. The ASDG TwinX/GPIB board >will NOT support DMA. However you can have the DMA request trigger an >interrupt. Hmmm, the product sheet from ASDG indicates a Programmed I/O rate of 70 Kbytes/Second(Typ.) and a DMA I/O rate of 300 Kbytes/Second(Typ.). Also, indicates a SBX Compliance of "D8 DMA (Eight Bit Module With DMA Support)". Sounds to me like the iSBX module supports DMA ?? >>Q: ASDG TwinX boards: Since I haven't tried to access custom hardware >>the system, does ASDG provide software to access TwinX modules? Can >>one purchase driver source code? >Dunno, you might wanna ask Aaron Avery (aaron@madnix.UUCP) or even >Perry K. himself. ASDG sells you a driver (GPIB.library) with the >stuff, though. What kind of functions are provided? I still haven't gotten around to writing a letter request. I kinda was hoping they would respond to my telephone and email requests. >>Q: What modes of access to the PC bus are available from the Amiga >>side? Do I have to involve the 80xx.x in the process, or can I read the >>AT bus directly? > >Nope, the AT bus only shares the power with the rest of the Amiga. You >must either use a CBM Bridgeboard or wait for that dumb but fast and >cheap connection bridge that was proposed here some months ago. >But with your knowledge and resources a "dumb" bridge should be nooo >problem. (Thus spoke the softhead and quickly fleed. :-) I have trouble believing it would be easy since the PC boards don't expect a synchronous bus & one would have to account for board timing problems with the interface. Actually, if the project comes up, I might have our hardware guys take a look at such. Looks like I ought to start collecting the information. On the other hand, having a 80xx out there pre-processing the data has it's advantages also. I've done this type of stuff on a PC - utilizing 8088's on peripheral boards with shared buffers for commands/data to be exchanged between the processors. Kind of a cludge getting things started up though. Does the new BridgeBoard software have adequate support for inter-system communications such as this? Is it fast? Thanks, ======================================================= Kent Polk - Southwest Research Institute {cs.utexas.edu, gatech!petro sun!texsun}!swrinde!kent kent@swrinde.nde.swri.edu ------------------------------------------------------- "Anything worth doing is worth overdoing" =======================================================
balzer@frambo.dec.com (Christian Balzer) (06/29/89)
In article <17837@swrinde.nde.swri.edu>, kent@swrinde.nde.swri.edu (Kent D. Polk) writes... > >Hmmm, the product sheet from ASDG indicates a Programmed I/O rate of 70 >Kbytes/Second(Typ.) and a DMA I/O rate of 300 Kbytes/Second(Typ.). >Also, indicates a SBX Compliance of "D8 DMA (Eight Bit Module With DMA >Support)". Sounds to me like the iSBX module supports DMA ?? > Uh, I guess I should make more clearly statements, let me re-phrase my first answer: The TwinX card can't do DMA to/on the Amiga bus. Period. A shame... BUT... you can set it up in a way that DMA requests from the mounted iSBX modules (which of course support DMA) triggers an interupt in the Amiga that could/should call a fast data transfer routine. Better phrased??? > >What kind of functions are provided? I still haven't gotten around to >writing a letter request. I kinda was hoping they would respond to my >telephone and email requests. > Dunno, I might be able to tell you in a few days, but you should keep firing shoots at ASDG. ;-) > >Does the new BridgeBoard software have adequate >support for inter-system communications such as this? Is it fast? > Yup, it has such support, although I can't comment on speed or adequacy. Become a registered developer. Get the Janus 2.2 Gamma 2 developer disk that was distributed at the SF DevCon. Regards, - <CB> -- _ _ / / | \ \ <CB> aka Christian Balzer - The Software Brewery - < < |-< > EMail: ...!decwrl!frambo.dec.com!CB -OR- CB@frambo.dec.com \ \_ |_/ / E-Net: FRAMBO::BALZER | Home-Phone: +49 6150 4151 (CET!) ------------ PMail: Im Wingertsberg 45, D-6108 Weiterstadt, F.R.G.