- From: Francisco Mota <mota_at_dca.ufrn.br>
- Date: Wed, 24 Oct 2007 10:28:49 -0200
Hi Tim, Thanks for the answer. The point is that we are trying to control the speed of an induction motor and the timing is very resctrict - we need one thread to make 06 AD readings in less than 100us! - that's the point. Maybe the hardware can't do that (if there is a lot of iniatiating overhead as you pointed out). Cheers, Francisco Mota. Tim van Zon escreveu: > Hi Francisco, > > could you try to read 6 million samples instead of 6? (should take > about 48 seconds :-) ) I expect that there is a lot of overhead for > initializing the card and furthermore, I think that the timing is not > that accurate as well. > > Tim > > Francisco Mota wrote: >> Hi folks, >> >> We are having the following problem with Advantec PCI 1710 AD/DA >> Board: The AD convertion time interval is being much greater than >> specified in the manual. We made a test with 06 (six) consecutive >> readings in the AD channel and the total time spent was more than >> 100us. Looking in the manual we saw that the AD conversion time is >> 8us, so, we should have 48us in average. Does anybody has had this >> problem before? any help will be appreciated. >> Our configuration is: >> Pentium IV 2800 MHz, 512 RAM, running Linux Slackware 10 - Kernel >> 2.6.8.1 with RTAI 3.1, Comedi 0.7.70, Comedilib 0.7.22 >> >> Thanks, >> Francisco Mota. >> >> _______________________________________________ >> comedi mailing list >> comedi_at_comedi.org >> https://mail.comedi.org/cgi-bin/mailman/listinfo/comedi > > _______________________________________________ > comedi mailing list > comedi_at_comedi.org > https://mail.comedi.org/cgi-bin/mailman/listinfo/comedi
Received on 2007-10-24Z11:28:49