Pausing (e.g. in a debugger) causes all subsequent APIs to fail


If you use a debugger on a C program that uses the Sensel API, set a breakpoint, and hit the breakpoint after calling a few APIs, all subsequent APIs will fail (with a “Failed to receive ack from sensor” error). I believe that any pause (due to a breakpoint or some other non-debug-related pause in the program) will cause the same failure. I noted this behavior very early on (at this no-longer-valid link):

but that issue didn’t make it over to this new forum. This issue can often be worked around, but ultimately this is a pretty serious issue, since if someone ships a program that uses the API, and that program pauses after startup, for any reason, it will fail completely. I currently use a separate executable for tracking things with the Morph, and send OSC/TUIO to a second program. I would like to embed Morph support directly in the second program, but this issue prevents me from doing that.


This issue continues to plague me - I’m now actively trying to embed Morph support inside a FreeFrame plugin, to make it easier to distribute rather than requiring/using the separate TUIO server in After embedding it, I’m finding the same issue - after pausing in a debugger, all APIs fail.

Is anyone else affected by this issue?


Hi Tim,

Sorry for the delay. We are looking to add a register to the Morph that allows you to keep it the protocol open and prevent the device from timing out (which is causing the issue during pause). I will make sure to post here when the update has been released.



Hi Alex - thanks for the report, I’m very happy that the problem is understood and a solution is forthcoming.



I just wanted to chime in and agree that a fix to this issue would be most welcome.


Any progress on this? I’m now faced with an intermittent bug, and the inability to pause and continue is making it extremely difficult to track down.


Facing this error as well while working on a TouchDesigner mod. It’s difficult to figure out where to initialize the handles if I’m unsure when readSensor will be called next.


It’s a year since the last update on this issue. Just ran into it again. What’s the status?



Hi Tim, sorry for no updates. The previous solution ended up not working but we have a few other potential solutions. I will try to keep this thread updated when they are tested.