Hello,
I have big problem with your Up/Down counter K8035.
I use it for countig outputs from Incremental rotary encoder ( IRC ). When I count output directly from IRC, everything is ok. But I need know direction, so I use LS7083 chip ( datasheet is in attachement ) to detect this from IRC outputs. And there is a problem. Output from LS chip is probably too short ( 250 ns - 25 mikro s ) for your counter. I think, that your counters is software treated before errors and this pulse width is too short for them.
Can you reprogram your procesor PIC16C57 ( used in K8035 ) to read pulse width from 20 mikro second or less ?
Best regards,
Frantisek Pajisek,
Prague, Czech Rep.