I am trying to work with this new raspberry pi modem HAT. Currently I am attempting to work the modem with my computer through USB and putty. I can send and receive commands through serial but nothing I do gets the modem to see RF signals or register the SIM. The test setup is as follows:
Connected bench top PSU to the board capable of supplying up to 5 amps at 5 volts. (it draws about 80mA when its on and searching for signal, 50mA when idle). This should eliminate any under current issues.
Connected a large 4G LTE CradlePoint brand antenna to the LTE port on the board. I have also tried several times with the Sixfab supplies Pulse Electronics one. I am also in an area with excellent AT&T 4G LTE signal.
Connected the Sixfab board to my computer through the micro USB cable and started a terminal session.
I turn on the power, wait 10 seconds then press the “pwrkey” button for 3 seconds. This wakes up the modem and then I can see the COM port display in my device manager. I then connect to the device through putty at a baud rate of 115200bps.
Ensured that the AT&T SIM I am using is active. It is a Data only line with a private APN and static IP. I tested this SIM in two separate 4G CradlePoint modems and it works fine.
Serial log with notes (#)
# I set echo on
# I set error codes to verbose
# display product info, modem mnfc, model, revision
# Quectel modem IMEI number
# display status of the SIM. Ready indicates it does not require a PIN
# query the initialization status of SIM card. (e.g. 3=1+2 means CPIN READY & SMS DONE).
# display SIM card number
# display SIM International Mobile Subscriber Identity number
# display phone functionality. 1 = Full function
# display Signal Quality Report. RSSI and BER = Not known or not detectable
# Network registration status – Disable network registration unsolicited result code & Not registered, but MT is # currently trying to attach or searching an operator to register to.
# Network Registration Status – Disable network registration unsolicited result code & Unknown
# EPS Network Registration Status – Disable network registration unsolicited result code & Not registered, but MT is currently trying to attach or searching an operator to register to.
That’s as far as I have gotten. Any ideas?