Problem with 16F688 and using PORTA as digital inputs - I'm pulling my hair out!

[Christopher4187]

I've been out of the loop for quite some time but I have a need for a small project. I'm using a 16F688 and trying to use PORTA to read digital values (button presses). I've read the data sheet and tried adjusting the code but nothing seems to work. I've stripped the code down to the bare minimum, even removing all of the analog stuff (I think), but it's still not working:

@ DEVICE PIC16F688, INTRC_OSC_NOCLKOUT,WDT_ON, PWRT_OFF, MCLR_OFF, BOD_ON,PROTECT_OFF           
      
TRISA = 111111
TRISC = 111111
ANSEL =  000000
CMCON0 = 000000    
ADCON0 = 000000        
DECREASEBUT VAR PORTA.3
INCREASEBUT VAR PORTA.1
ENTERBUT VAR PORTA.4       
MODEBUT VAR PORTA.0
LED VAR PORTC.1 

Start:
IF INCREASEBUT=0 THEN GOTO INCREASE
GOTO START


INCREASE:
HIGH LED
PAUSE 500
LOW LED
PAUSE 500
GOTO START

It's blinking the LED even though 5VDC is on A.1. The same goes for A.5, A.4 and A.0. When I press a button on A.3, the MCU resets as if the MCLR is enabled but I set MCLR to off. There is probably something simple I'm overlooking. Can anyone help me?