PIC24HJ128GP210A-I/PT controllers issue

[sr_viss]

Hi!
We have discovered very strange function on PIC24HJ128GP210A-I/PT controllers.

PortB is configured as digital input
PortE is configured as analog input

If there is digital signal present on PortB pin RB0, then AD conversion data from PortE is "slightly" corrupted on every other conversion result. AD data seems to follow analog signal, but you have slightly higher values on every other conversion results. It sort of works, but it does not.

If we remove digital input signal from PortB pin RB0, then AD conversion on PortE works perfectly.
We have now left RB0 pin unconnected and that has fixed our problem, but it would be nice to know what could cause this kind of behavior.

PortE AD was read with both DMA and polling methods, there was no difference how you read the AD data, half of the data was "slightly" corrupted every time when PortB RB0 had digital signal present (encoder in our system)
AD port has external references on PortA.

Best Regards

[IvanJeremic]

Hi,

I don't see any specific reason why this would happen, it could be that you did not set the RB0 pin correctly, or something similar.
https://ww1.microchip.com/downloads/aem ... 80468G.pdf
https://ww1.microchip.com/downloads/aem ... 70592d.pdf

Thank you for sharing this issue with the MikroE community.

Regards,

Ivan.