Similar to a few other posts on this forum, the BNC outputs of a couple of our Bpod SM r2.5 appear to no longer be working. We send TTL pulses from the TTL I/O out1 and out2 channels of the bpod to spikeGLX, and those pulses no longer show up in spikeGLX. When I plugged in a different Bpod SM r2.5 without changing the code, any of the cables, or the PC, the TTL pulses show back up as expected, suggesting that the bpod itself is the issue.
Additional Information:
- So far, we have noticed this problem with two of our Bpod SM r2.5, and I believe they came from the same order placed in December 2024. Although I will have to verify that if needed. This problem did not arise if the first bpod we used for a few months, but it only took a few weeks for this problem to show up in the second unit.
- We are using the python firmware and pybpod. Another post suggested that updating the firmware temporarily solved the issue. I will investigate to see if updating to the matlab firmware and then reinstalling the python firmware fixes the problem.
- I have not yet used a multimeter/oscilloscope to directly measure the output from the BNC ports. I will do so in the next couple days and update this post with my results.
- Turning the bpod on/off (by unplugging and plugging it back in) has not fixed the issue.
- Both the USB and 12-24v pwr cables are plugged into the bpod, as well as a port interface module. The bpod is still controlling the port interface module just fine, the only issue is with the TTL.
Do you have any ideas on how we could fix this? Both times we have encountered this problem-- the SM r2.5 no longer sending TTL pulses-- switching to a new/different bpod has resolved the issue. To me, this is indicative of a hardware or firmware problem, but I don't know how to further diagnose the problem.
