This is an issue from my previous topic, but I would like to open another one because I can reproduce the error now.

I have three quadrature encoders plugged into the cortex, and 11 out of the 12 digital ports are being used. When I plug these quad encoders into different ports and 'open debugger manually' in robotC to view sensor values, the encoder which has a wire plugged into port 4 can have invalid values of -1, 0 or 1.

Here are the steps to reproduce the error.

1. Plug the three encoders in port 1&2, 3&4, 5&6, the middle one works some time, but no longer working after a cortex restart.
2. Change them to 1&2, 4&5, 7&8, the middle one will always give values of -1, 0 or 1

Finally I plug these encoders in port 1&2, 5&6, 7&8, now they are working properly.

The Attached files shows the setup of the robot. I am using the latest robotC 4.30 and updated to the latest cortex firmware.

Is this a bug or feature in robotC or the VEX cortex?