Hamid Sadeghian

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6 years, 11 months ago.

GSM module is not working

Hello guys,

I'm using the GSM library to drive a GSM 800L modul with STM32F767 Nucleo board. I checked every thing many times. (the Wires, Pinmaping, Baudrate, ... ) it seems everything ok but still not working. As I traced the program I fined out the MCU send command to GSM correctly but doesn't receive any response.(just space character, Ascii code '32'). Anybody could help me ? Or maybe oder GSM library? I would appreciate if someone could help me.

thanks,

Hamid

Hi Hamid, have you tried to communicate with the GSM module directly (without the Nucleo). I mean for example directly with you computer trough an USB to Serial adapter using some Console Software?

Could you please provide a reference (link) to the module?

Best regards.

posted by Felícito Manzano 04 May 2017

Hi Felícito, thank you for reply. I orderd a USB to Serial convertor but still dont have it. I can communicate with the GSM using Arduino uno. So I can be sure there is no problem with GSM module.

here there is a Link: http://www.ayomaonline.com/programming/quickstart-sim800-sim800l-with-arduino/

Best regards, Hamid

posted by Hamid Sadeghian 06 May 2017

1 Answer

Sanjiv Bhatia
6 years, 11 months ago.

Hi Hamid. Can you post your code ? Please apply the <<code>> your code <</code>> markers before posting for best viewing of your code. At this stage of debugging, the issue is linked to standard serial communications @ 9600 bps. One idea to test is to mate your Arduni Uno (UART pins without any RS232 transceiver) and connect to your Nucleo UART pins. So this means, TX to RX; RX to TX and common ground. Again, no RS232 transceivers. The STM32 processors are FT on the UART pins so this means the port pins are 5 volt tolerant and not at risk of being damaged. Then proceed to transmit @ 9600 baud "01234" or whatever and then confirm the Arduino can receive this information that was sent by the Nucleo -> then do the opposite and send from the Arduino to the Nucleo. This will be a great test to confirm the wiring is solid and that the mbed libraries are not the issue.

Someone posted some issues with the serial port and your Nucleo here:

https://developer.mbed.org/questions/76590/The-readable-function-does-not-work-once/

Please post your code and results after testing.