A way to use software serial in debugging

[jdolinay]

A way to use software serial in debugging

[jdolinay]

Hi,
I think Software serial internally uses interrupt for receiving data and unfortunately the interrupts are blocked by the debugger if there is one or more breakpoints set. So the Software serial cannot receive data. This is due to the implementation of the debugger. I can suggest 2 options in your situation to bypass this limitation:

1. If you remove all breakpoints (including the automatically inserted breakpoint in main which VS code inserts - this requires executing command -exec clear main in the Debug Console, see the doc, chapter Breakpoint in main). So if you remove all breakpoints and let the program run, it should be able to receive data. The problem is that you can only stop it by the pause (suspend) button so it will stop at random moment. But maybe this can still be useful to inspect the data. Actually, you can also insert the breakpoint() function in your code at the line in code where it should stop and it should stop at this line always. Perhaps inside some condition which is true when complete data is received.

2. If you use the "flash breakpoints" configuration (which requires replacing the bootloader in your arduino), it should work with breakpoins - you can place breakpoint and let the program run. It should then stop on the breakpoint.

Anyway, I am not sure if it will work :( The software serial may need quite precise timing of its operations to be able to sample the input pin which may be disrupted by the debugger. I think it could work as described above but maybe this is something for which the debugger is not useful.

Best regards

[wanggaoteng]

Hi, Jan,
Thank you very much. I test 1, but it doesn't work.
I realized that it may be the limitation of gdbstub to receiving data, so I can only close this issue.
Best regards.