Please ensure that developers have completed the checks outlined in Section 6.1 of the MRS2xx  mmWave Radar Sensor Host Development Manual to guarantee proper communication.

• Sync Timeout During Firmware Download

   1. Verify that the hardware communication lines between the Host MCU and the sensor are correctly connected.

   2. Check the driver ported according to Section 2.4 of the  MRS2xx  mmWave Radar Sensor Host Development Manual . Follow Section 6.1.1 to verify if it can normally and correctly transmit the expected data.

   Typical Debugging Method: Use a logic analyzer to inspect the bus and verify the correctness of the data transactions.

• Failure at the Last Packet During Firmware Download

Please update to the latest HOST_DRIVER. Then, check if the vendor_image_read interface (Section 2.5 of the  MRS2xx  mmWave Radar Sensor Host Development Manual ) is correctly implemented. Pay special attention to whether the firmware's starting address is correct.

• Unsupported Error Codes or Checksum Errors During Firmware Download

After implementing the vendor_xxx_read interface ( Section 2.4 of the MRS2xx mmWave Radar Sensor Host MCU Development Manual ), check if the function only exits after reading/writing len length of data, and use a logic analyzer to check for packet loss. 

    UART Communication: Check if the interface is dropping packets because the MCU cannot receive/process the data fast enough (e.g., buffer overruns).

    I²C Communication: This typically occurs with Software I²C. Verify that your communication strictly adheres to the standard I²C protocol timing.

    General typical troubleshooting method: Use a logic analyzer to verify the correctness of the bus data transactions.

• Sensor Fails to Start/Stop After a Successful Firmware Download

    Start/stop commands will only be acknowledged if the firmware has been completely downloaded and successfully executed. If the firmware has not been downloaded, please download it first. If the download is complete but commands still fail, consider a firmware boot failure on the sensor and check the following:

    Check whether the original firmware data is consistent with the data downloaded by the host MCU. For example, if the firmware is stored at the host MCU's flash address 0x32000, a mismatch between the read address during firmware download and the actual storage address will cause an error in the downloaded firmware.

• Considerations for Software I²C

•  Whether the GPIO supports open-drain capability：

    With Open-Drain capability: To output low, use open-drain mode and output 0. To output high, use open-drain mode and output 1. To read the logic level, read directly in open-drain mode.

    Without Open-Drain capability: To output low, use push-pull mode and output 0. To output high, configure the pin to input mode with a pull-up resistor. To read the logic level, configure the pin to input mode with a pull-up resistor.

• Additional Implementation Notes：

   After completing the procedures in Section 6.1.1 of the MRS2xx mmWave Radar Sensor Host MCU Development Manual, it is recommended to check whether the bus is busy after receiving an ACK for the read/write address. If busy, wait; if not busy, proceed with the data read/write.

   If the bus remains constantly busy, please verify that your GPIO implementation is not holding the bus low (locking up the busy) during the busy check.