I am posting for help on using the serial port on pins 5 and 7 on the low speed expansion header.
I am aware that the port is located in /dev/tty96B0 -> /dev/ttyMSM1 and have confirmed that the port is being seen by the db410c via an 'ls -l'
I am trying to send some data to the db410c from a microcontroller via this uart port. I have confirmed that my issue is not on the microcontroller end both using a different single board computer running debian (beaglebone black), and the serial debug console on my microcontroller. I have also confirmed that the baudrates and parity settings on both ends are matching.
The microcontroller is triggered off of a serial event.
Here is a minimal example of what I am trying to do (I'm using python):
ser=serial.Serial('/dev/ttyMSM1', 115200) #Baudrate matches microcontroller
ser.write('event') # Trigger microcontroller
while ser.inWaiting()==0: #Wait while theres nothing to read
This hangs up during while waiting for there to be something to read. I have also confirmed that nothing is being written to the serial buffer on the microcontroller. This heads me to believe, having confirmed that my wiring is fine, that there is some sort of pin mapping/muxing issue with the UART that I am not resolving properly.
Are pins 5 and 7 on the LS connector NOT mapped to UART0 by default? I have also tried simply connecting RX to TX and have not even gotten the port to talk to itself, so I believe pin mapping/muxing to be the most likely issue here.
Available documentation on this sort of thing seems to be geared toward the Android developer crowd, and has not been very helpful to me. If anyone here has any insight into or experience with this issue I am describing please do let me know.
Thank you in advance.