I'm struggling to talk to a modem over the UART. The UARTs in question are 1 and 2, which I enabled using the Adafruit python library.
They can talk to each other fine so I presume they are set up fine. The problem is that after going through a level shifter they seem unable to communicate to my devices. The GPS module sends data, and it can be received no problem, but sending data seems to be a problem. I have two specific questions. 1) should I be using a common ground? At the moment I am using two separate power supplies as I can't draw power from the BBB. There is currently no ground common to both. 2) is the transmission power from the tx pin high enough to get through the level shifter? Does anybody know what the power of these tx pins are? GPRS module is SIM900, and works fine with my power supply if connected to my PC via a USB to TTL adaptor. Any other pointers gratefully received! -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
