Firmware Update fails with Verification Error
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SKU: DFR0398
Arduino IDE: 1.8.5
Intended function - move 3 DC motors with encoders
Issue: sketch upload to flash is unreliable. The flash size is 512k, but when the sketch size is around 33k, the sketch upload sees 'read verification error' from 'avrdude' in 2 out of 3 attempts.
With addition of more source code, when the sketch size became 40k, the sketch upload sees 'read verification error' from avrdude every time - unable to upload the sketch in over 50+ attempts.
When I tried a simple sketch which prints out "Hello World", the size of the sketch was 5k, and I still saw the 'read verification error' from 'avrdude' every now and then, but it is rare for 5k image.
After digging more from the logs -> read verfication error seems to occur, when avrdude program reads the flash data, and compares it with the image, and finds mismatch at some point. The byte index of first mismatch is also changing every time.
Arduino IDE: 1.8.5
Intended function - move 3 DC motors with encoders
Issue: sketch upload to flash is unreliable. The flash size is 512k, but when the sketch size is around 33k, the sketch upload sees 'read verification error' from 'avrdude' in 2 out of 3 attempts.
With addition of more source code, when the sketch size became 40k, the sketch upload sees 'read verification error' from avrdude every time - unable to upload the sketch in over 50+ attempts.
When I tried a simple sketch which prints out "Hello World", the size of the sketch was 5k, and I still saw the 'read verification error' from 'avrdude' every now and then, but it is rare for 5k image.
After digging more from the logs -> read verfication error seems to occur, when avrdude program reads the flash data, and compares it with the image, and finds mismatch at some point. The byte index of first mismatch is also changing every time.