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start:
init:
clrf PORTA ; make sure port A output latches are low
clrf PORTB ; make sure port B output latches are low
bsf STATUS,RP0 ; select memory bank 1
movlw b'11111111' ; set port A data direction to inputs
movwf TRISA
movlw b'00000000' ; set port B data direction to outputs
movwf TRISB
bcf STATUS,RP0 ; select memory bank 0
goto main
;; for this program use the 2k 8 bit mem chip, with WE on B2, OE on B3, and the memorys 3 least
;; sig bits to B4-B6 (inclusive), all other pins on the mem chip need to be held low, and an led
;; needs to be on B1
;; when B1 goes high move the 3 pins from the microcontroler to leds and see the value
main:
movlw b'01111000'
movwf PORTB ; make we high, oe low, and 3 pins high
call wait1000ms
movlw b'00000110'
movwf PORTB ; make we low, oe high, and 3 pins low
noend:
goto noend
END ; ends the program
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