send TTL via the parallel port under Linux

Question

Leila Azizi 2023-1-16

回答： Atharva 2023-3-29

Hello,

I am trying to send the TTLs via the parallel port under Linux.

I tested ppdev-mex from https://github.com/widmann/ppdev-mex. Here is my code:

ThemeCopy

ppdev_mex('Open', 1);

lptwrite(1, 255)

ppdev_mex('Close', 1) ;

The problem is that I don't get an error, but nothing happens. In Python, I can send the trigger via the port:

ThemeCopy

PORT1 = '/dev/parport1'

Do you have any idee?

Answer 1

Atharva 2023-3-29

Hey Leila,

Here are some steps you can try to troubleshoot the issue-

Check if the parallel port is detected by the system: Make sure that the parallel port is properly detected and configured by your Linux system.
Check if the ppdev-mex library is installed correctly.
Check if the ppdev kernel module is loaded.
Check if the user has permissions to access the parallel port.