Help with PD78C12ACW-675 microcontroller from a Tascam Portastudio recorder

[faxika]

Hello,

I`m trying to bring back to life a old Tascam Portastudio 464 which have this microcontroller in it that control the commands to actuate the motors, LCD screen and recording signals.
So, Im having an issue that it only plays for a little bit and for some reason the microcontroller gives a signal to STOP the machine
I`m suspecting that the microcontroller has been shorted by someone before, but I don`t know how to diagnose this
Since I don`t know much about digital eletronics, maybe you guys could shine a light to me in these readings I made from 2 pins (one from ALE pin and other from MODE1 pin) that looks weird to me. I attached pics so you guys could see.

As far as I read the microcontroller manual, these pins should be just a HIGH or LOW signal, not a bunch of noisy and scrambled signal, or Im wrong?
Theres no component attached to these pins that haven`t passed an eletronic test, they look good, thats why im suspecting that the microcontroller is bad, but I never fixed something with digital eletronics, I only repaired analog eletronics so far.