Communication with BG96

[tobias]

Issue:

We have some weird behavior with the communication with the BG96 modem.
Most of the times we get a strange set of charecters as response from the modem (sometimes also no response):

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Setup:

• Board: RAK5010
• Dev-Setup: Visual-Studio-Code + Arduino
• I initialize like in your examples Serial & Serial1 with a baud-rate of 115200 (but also tried different baud-rates)
• I send at-commands like in the example https://github.com/RAKWireless/Arduino-on-Rak5010-/blob/master/Rak5010.ino#L40 with the timeout of https://github.com/RAKWireless/WisBlock/blob/master/examples/communications/Cellular/Cellular_Ping/Cellular_Ping.ino#L65.
• Debbuging through USB
• I also tried with and without additional power-supply (USB Charger 5V)

at command send:

void bg96_at(char *at, uint16_t timeout)
{
  bg96_rsp="";
  Serial.println("at command:");
  Serial.println(at);

  char tmp[256] = {0};
  int len = strlen(at);
  strncpy(tmp,at,len);
  uint16_t t = timeout;
  tmp[len]='\r';
  Serial1.write(tmp);
  delay(10);
  while(t--)
  {
    if(Serial1.available())
    {
      Serial.print("+");
      bg96_rsp += char(Serial1.read());
    }
    delay(1);
  }
  Serial.println("");
  Serial.println(bg96_rsp);
}

Do you have any idea ?

[nero (du)]

Hi，
What voltage of GPIO do you set? It is set in bootloader and should be 1.8V. Another point is not using the softserial. Our code about 5010 and wisblock are different. So I advise you use the bootloader in Arduino-on-RAK5010 github.

[tobias]

Hi nero, thanks for your reply.
I did not update the bootloader yet, @Fomi & @Nancywang prepared the RAK5010 with a bootloader, so I thought its already the right one on it ?!

But as I have a Segger J-Link JTag Debugger, I could also update it.

So you recomend me to flash the https://github.com/RAKWireless/Arduino-on-Rak5010-/blob/master/feather_nrf52840_express_bootloader-0.2.13_s140_6.1.1.hex with JFlash to the RAK5010 ?

[nero (du)]

Right, the strange set of characters is due to the GPIO volgate config. Replace the firmware with https://github.com/RAKWireless/Arduino-on-Rak5010-/blob/master/feather_nrf52840_express_bootloader-0.2.13_s140_6.1.1.hex

It will solve the problem if communication with BG96.

[tobias]

thanks nero, this solved the Problem!