Hello everyone。I face a difficult problem。i use cortex-m4 to send data from own serial to the HTCC-AB01’s serial.Moreover，i use line to connect the m4’tx and AB01’s rx.unfortunately,whatever i supply power to each other or use AB01 to supply power to m4.the date i received are all zero
Connected GND between m4 and AB01? Check what the ABo1 get from serial!
yeh，i connected GND between m4 and AB01,but this problem still existed.
Same baud rate and stop-bit configurations?
yes,these things are all examined i promised。
make a test serial connection without loRAWAN. Put the output to a serial monitor!
Check behavior of deepsleep!