Timing Issue

We have a Siemens TIM Trio 3T, Eprime, and Lumina (LSC 400B) set-up. We are having intermittent issues with the trigger. Sometimes after a run (where the task and sequence have finished), the trigger light remains illuminated. As a result, the subsequent task will not be perfectly synced with the scanner (it will be delayed by a couple of seconds). Does anyone know how to reset the trigger from the Lumina box? Any thoughts or comments are greatly appreciated!

When the experiment finishes running and the trigger light is still illuminated, what happens if you turn the Lumina controller off and back on?

Unfortunately, the light remains illuminated when we turn the box off and then on again. Is there a way to reset the light from the box?

This is not a timing issue. The trigger input accepts “differential voltage” signals, meaning that there is no ground and therefore no reference, so the Lumina LSC-400 controller makes an assumption. In your case, it happens that the assumed default is incorrect. This does not affect in anyway the output from the serial port or Accessory Connector; it affects only the light on the front panel.

It is possible to change this default using a utility program called Xidon (pronounced Zydon). It is a program that was intended for in-house use only, but here is the link. The controller needs to be in “Lumina” mode before Xidon can recognize it. Once Xidon can auto-detect the controller, click on the Device menu and choose MRI Scanner Trigger Input. In the dialog that appears, change “Normally OFF” to “Normally ON”.