Encoder problem

[mister_e]

My rules:

1. Don't use Serout when the PIC have an internal USART, use HSEROUT instead.
2. use Timer as counter when hardware allow
3. keep ISR as short as possible to avoid latency etc etc

In this case, i guess, you could remove the interrupt and do the job by reading the Timer register. Working 'round the multiple if/then statement you can improve it.

also...

OPTION_REG = %00000000
On Interrupt Goto myint
INTCON = $90


IF PORTA.0 = 1 THEN NINE
LOOP: serOUT PORTC.6,T9600,[#b5,#b4,#b3,#b2,#b1,13]

When you start the PIC and IF PORTA.0=1 you make it jump to the ISR? Bad practice