TTL input - 3rd states possible?

[sougata]

Hi,
This is just an idea using the MChip Tips n' Tricks. No timer, no comparator just an idea. Flotulopex please test it out. Others on the forum please comment if it is crap.

READ_SWITCH:
TRISA.0 = 0             ' MAKE THE PIN AN OUTPUT
PORTA.0 = 0             ' MAKE IT LOW
PAUSE 100               ' WAIT FOR THE CAPACITOR TO DISCHARGE 

TRISA.0 = 1             ' MAKE THE PIN AN INPUT
PAUSE 100               '

IF PORTA.0 = 1 THEN SWITCH_HIGH   '

LED1    = 0             ' DEFINATELY NOT HIGH
TRISA.0 = 0             ' MAKE THE PIN AN OUTPUT
PORTA.0 = 1             ' MAKE IT HIGH
PAUSE 100               '

TRISA.0 = 1             ' MAKE THE PIN AN INPUT
PAUSE 100               '

IF PORTA.0 = 0 THEN SWITCH_LOW   '
LED0       = 0          ' DEFINATELY NOT LOW

GOTO READ_SWITCH

SWITCH_LOW:
LED0 = 1
GOTO READ_SWITCH

SWITCH_HIGH:
LED1 = 1
GOTO READ_SWITCH

P.S. - The code can be made shorter!!