trigger

[Don.Rojas at UCHSC.edu]

Ted,

Below I have included a snippet of code that works well for me.  If the code
sample you have supplied is all you are doing, the TTL pulse is probably too
brief too see.  Another thing to check is to make sure your port address is
really &H378.

Don Rojas

Sample trigger code:

Dim StartTime as Single
Dim TimerDuration as Single

TimerDuration = .005
StartTime = Timer

do
	WritePort &H0378,1
Loop Until Timer > StartTime + TimerDuration

WritePort &H0378,0


-----Original Message-----
From: Theodore Steger [mailto:theosteger at di.mdacc.tmc.edu]
Sent: Monday, April 24, 2000 11:27 AM
To: eprime at CHILDES.PSY.CMU.EDU
Subject:





Hello all.

I'm trying to use the parallel port to send a trigger pulse to start an MR
scanner.  I've been using the WritePort command but when I
put a meter to the parallel port pins, I get no output.  The command I'm
using
is

WritePort &H378, 1

Any suggestions you may have will be appreciated.  Thank you.

Ted Steger