Arduino Due and Serial Connections

Official Hardware Mega Due
1

I am trying to connect both the SM5100B shield (serial 3 on Due) and a puprletooth jamboree bluetooth module (Serial2 on Due). When both are connected to Due only the BT module works and the cellular shield stops responding. Both are connected to an external power source. Any idea as to why? Is the board unable to drive both together? How can this be resolved?

Thank you.

2

Perhaps the fault is in your code - which you haven't posted... Multiple
serial devices requires fully asychronous (non-blocking) I/O.