Presentation

[Dar Scott]

On Monday, March 22, 2004, at 03:41 AM, Jordi wrote:

> I am trying to make a presentation software to present visual and 
> auditory stimuli and to send marks to a electrocardiogram recorder 
> (BIOPAC System). I know runRev can 'write to file "LPT1:"' but BIOPAC 
> waits for a TTL pulse. I don't know where is the lost link. How could 
> I send a code trough the paralel port in a pulse form? Anybody can 
> help me in this topic?

It might be that the last character written to LPT: is on the 8 
character output lines.  You might be able to generate a pulse by 
writing numToChar(1) and then numToChar(0).  The driver will expect a 
handshake, so that might be a problem.  You might be able to get around 
this by opening and closing the port.  Or maybe you can loop back some 
other line.  This might require the classic parallel port mode.

Another approach would be to use a generic I/O port driver that you 
open and send a control byte stream.  There are a few around.  The name 
DriverLynx comes to mind, but that might be something else.

Another approach is to use RTS from a serial port.  Pulse it by opening 
and closing the port.  The voltage levels go outside of TTL, so you 
might need to do something about that.

Dar Scott