Hi, I am evaluating the A9G GSM/GPS module. I am using a ATMEGA328PB to communicate with the A9G module. When I connect a FTDI cable directly to the AT_TX / AT_RX ports of the A9G and use a terminal software on the PC, I can talk to the A9G with no problem. Using this setup, if I send the AT com…

The ATmega328PB has only one UART and one serial port. What Arduino module are you actually using?

I am using the A-Star 328PB Micro board from Pololu.

My mistake. The "PB" does indeed have two UARTs. The GSM module is the prime suspect, but a brief search revealed datasheets only in Chinese. Were you able to find full documentation in English?

I have confirmed that both the ATMEGA328PB and the A9G baud rates are set to 115200 Change the baud rate of A9G to 9600 Could you please share the diagram of the PWR_KEY part? Do you connect the mcu pin to pwr_key pin of A9G?

A9G GSM/GPS module outputs garbage

Projects Programming

Declan March 10, 2023, 5:44am 5

Hi,
I managed to overcome this by changing the baud rate in the A9G module

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A9G GSM/GPS module outputs garbage

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