- From: Muks Raju <muks_at_ieee.org>
- Date: Fri, 1 Aug 2003 00:17:35 -0400
Hello Frank, thanks for the reply. Well 10ms is of no use to mesince I have to have a scan every 5ms. So i guess ill have to abandon the "command" method and use insn to read the channels. Am i using this from a RT kernel module? Yes I am.. well I dont have a RT scheduler running but I have comedi compile with RTAI support and I use rt functions in this module. Why do you ask? is there something I should be aware of? Thanks Muks ----- Original Message ----- From: "Frank Mori Hess" <fmhess_at_users.sourceforge.net> To: "Muks Raju" <muks_at_ieee.org>; <comedi_at_comedi.org> Sent: Thursday, July 31, 2003 11:35 PM Subject: Re: PC104-DAS16jr/16 callback -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Thursday 31 July 2003 03:06 pm, Muks Raju wrote: > Hello I continue to have problems with the PC104-Das16jr/16 and comedi. > I have a program which does acquisition of Analog inputs using the > callback feature. It is intended to sample every 3ms . On a toshiba > libretto with a NI AI 16XE50 DAQ the call back is called every 3ms. But > with the same program on the PC104-DAS16jr/16 the callback is called > only once in 60ms and hence within a few seconds i get a buffer overrun. > Any inputs would be much appreciated > > Muks Yeah, that's right. If you are using the driver's timer mode, that's how often it polls the dma transfer. The polling period could be made adjustable without much trouble, but even then the shortest period possible would be 1 jiffy (10ms usually). By the way, you aren't doing this from an RT kernel module are you? - -- Frank -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.6 (GNU/Linux) Comment: For info see http://www.gnupg.org iD8DBQE/KeAD5vihyNWuA4URAn+lAJ0Y3BUEihpASpcaytxCUaFo+eqpIQCfX/DV pSCUR9Cgv1hHSudBJeEoZNQ= =0vVa -----END PGP SIGNATURE----- _______________________________________________ comedi mailing list comedi_at_comedi.org https://cvs.comedi.org/cgi-bin/mailman/listinfo/comedi
Received on 2003-08-01Z03:17:35