I have a MA780 where I sent value 0X80 to register address 0xE via the Write Register command ( [15:13] = 0b100 ) . Initially everything was working fine, and I could read back the register value of 0x80 through the Read Register command ( [15:13] = 0b010 ). But now this is not working anymore. If I read back the register value I always read value 0x00 while value 0x80 should have been written. Reading back the angle via Read Angle command ( [15:13] = 0b000 ) still works fine. Nothing has changed in code. Is the MA780 partially broken? Does anyone have seen this issue before?
Thanks for sharing
With kind regards,
Gijs van Bussel
Hi Gijs,
Did you change anything or do additional testing between the time you were able to read properly and when it stopped working?
Best Regards,
Yu
No, I haven’t changed anything. I have other boards with same hardware and they are working fine.
I have now written a test sequence which reads out all registers. With a working board all values return the factory defaults as described in datasheet. The board which is not working reads all 0 on every register. But reading the angle still works fine .
Hello Gijs,
Have you tried to check if the MOSI waveform is as expected? You should probe it close to the MA780.
Best,
Carmine
Yes the mosi signal looks fine, good TTL levels and no noise on signal. I was also thinking if it might has to do something with MOSI because when sending 0x0000 the MA780 wil respond with 16 bit angle. But when I read a register I get 0x0000, so not a 16 bit angle and not a 8 bit angle with register value.
Hello Gijs,
It might be the sensor got damaged. Is it possible that an anomalous voltage was applied to MOSI?
Do you have an additional MA780? If yes, please replace the one that is not working and check if the read register is working
Best,
Carmine