Sending trigger via parallel port

[Ian-Max-Andolina]

I’ve never used the parallel port, so don’t know what current code may control it on Linux. There are many ways to send a trigger. But for many users USB I/O devices work well. In MATLAB there are several ways to control a serial device, including PTB’s IOPort, and comparing performance I found that IOPort is clearly the fastest (~60µs TTL switch time using an Arduino):

Serial port interface code -- a performance comparison

MATLAB has a fairly new (R2019B+) serial port interface, Serialport. Some of my arduino control code had previously used the serial command that MATLAB has now deprecated. So I was curious to compare the old and new interfaces. In addition I also compared IOPort, the PTB serial controller. For the test I basically toggled the state of a digital pin on a Seeduino Xiao as fast as possible. I used the legacy MATLAB arduino interface sketch, which receives and sends the data via USB serial commands…

What are the parameters of the trigger you need to send? Some hardware require strobed words with a trigger bit, others simple TTLs etc…

There is some more info here:

FAQ: TTL Triggers via USB

And some specific details for the LabJack:

LabJack

And Arduinos:

Arduino

@xiangrui from this forum made a response button + I/O box with very robust PTB support and high reliability that you can look at here, this would also allow you to compare timings to a photodiode etc:

https://lobes.osu.edu/rt-box.php