I have the DMU381ZA unit with the SDK. I uploaded the original VG_AHRS (for DMU381ZI, no DMU381ZA available) firmware using VS Code. The unit connected to the Navigation Suite and I could see the acceleration, gyro and heading charts correctly. I installed the unit in my application with pin 7 grounded but still can't see a consistent UART message through pin 3 with the two starting bytes (0x5555). Initially I got some serial output without any 0x5555. I uploaded and tried using the compass app and got no serial output in pin 3. I tried another unit with the original INS app and again, got output only when using Navigation Suite but no UART output in pin 3. Am I missing something in the configuration process?