Digi XBee 3 Cellular LTE-M User Manual page 222

AT commands
PY^ (Interrupt Program)
Sends KeyboardInterrupt to MicroPython. This is useful if there is a runaway MicroPython program
and you have filled the stdin buffer. You can enter Command mode (+++) and send ATPY^ to interrupt
the program.
Default
N/A
Digi XBee® 3 Cellular LTE-M/NB-IoT Global Smart Modem User Guide
MicroPython commands
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