- From: David Schleef <ds_at_schleef.org>
- Date: Mon, 10 Mar 2003 10:28:33 -0800
On Mon, Mar 10, 2003 at 04:19:16AM -0500, William T Wilson wrote: > I am using one of the 8255 outputs on my NI PCI-6503 board as a latch > enable line. I want the signal to be pulsed as rapidly as possible, but I > still need to meet the timing requirements for my chip. > > Can anyone tell me, if I were to set a line on my PCI-6503 low, and then > immediately set it high again, with consecutive function calls, how long > the line would remain in the "low" state? Typically on the order of a few microseconds. > Is there any chance that making > the calls in rapid succession would cause some sort of problem, such as > the line not actually toggling under certain circumstances? No. Unless there's a bug. You should look at the insn.c demo in Comedilib. It shows roughly how to use instruction lists, which allow you to do multiple insns in a single system call, thereby decreasing overhead. You'll also want to look in the Comedilib reference for INSN_DELAY, which allows you to add programmable delays into an insn list. dave...
Received on 2003-03-10Z18:28:33