RAK3272-Sip can't join after burn firmware RAK3272-SiP_latest_final

Please help. After I burned the firmware RAK3272-SiP_latest_final.hex downloaded from the link below (RAK3272-SiP Breakout Board Datasheet | RAKwireless Documentation Center), I encountered a problem. The RAK3272-SiP restarts after sending the command AT+JOIN=1:0:10:8.

Welcome to RAK forum @nakorn ,

I haven’t encountered this yet but my idea would be.

  1. Your power source is not enough. When you issue a AT+JOIN the module starts to send an uplink. The spike of current causes drop down on the supply voltage which causes a brownout reset.
  2. There could be drop along the wiring from supply to the module. There are scenario the contact on the connector, header pins, jumper wires, breadboard, etc. causes the voltage dropo which result to a lower voltage.
  3. There could be corruption in the memory of RAK3172-SiP. Maybe try erasing the full memory then upload it again using STM32CubeProgrammer.

HI Carlrowan,
Thank you for your help. After I connected the 3.3V supply voltage to both pins of the RAK3272-SiP breakout board, the restart problem was solved, but it still cannot join the TTN network. How to solve it.

Hi Nakorn,

There are many reasons why, I will give some ideas:

  1. The end-device is out of coverage of the network. Maybe the gateway is too far. Or the nearest gateway is off. This is not an issue if you have your own gateway in your office/home.
  2. Antenna poorly connected on either the device and gateway or even on both. Also (rare case) wrong antenna is used. In some cases, antenna are too close to one another.
  3. Joining credentials are wrong - DEVEUI, APPEUI and APPKEY.
  4. Frequency band as well as mask is incorrect. If you are in US915, these setting must be the same on device, gateway and LNS. Also the mask should be the same.