I seem to be doing something wrong. I have connected a DroneCell to my Arduino Uno for testing, powering it with 5V. RX -> RXI and TX -> TXO.
Then I connect to it with screen over the USB cable like this (38400 baud was mentioned in the quick start guide):
$ screen /dev/ttyACM0 38400
Starting logging of the screen session (C-A H)
Then power cycle the dronecell. I See the TX LED flashing for roughly 1 sec. The output i get is as follows (no further input seems to be accepted, not further output sent):
$ hexdump screenlog.0
0000000 ff00 ffff fffe ffff
The expected output should look something like this (may vary when no SIM card is inserted):
Has anyone an Idea what's going wrong? Am I doin something wrong or might I have gotten defect hardware ?