Hi there, I'm working on a project for school and it is kinda confusing so I'm here desperately for help.
Assignment: " Connect PORTB to the 8 LEDs and PORTA to switches S10 to S14, with S14 the MSB. Write a program to add or subtract two Hex numbers (NUM1 + NUM2 or NUM1-NUM2) depending on the value of S10 (PORTA bit 0). If S10 is logic “0” the program will add the two numbers or if S10 is logic “1” the program will subtract them "
I came up with my code and this is what I have so far:
I would appreciate your feedback. Thanks!!!
Assignment: " Connect PORTB to the 8 LEDs and PORTA to switches S10 to S14, with S14 the MSB. Write a program to add or subtract two Hex numbers (NUM1 + NUM2 or NUM1-NUM2) depending on the value of S10 (PORTA bit 0). If S10 is logic “0” the program will add the two numbers or if S10 is logic “1” the program will subtract them "
I came up with my code and this is what I have so far:
Code:
#include <GENERAL.H>
; =======================================================================
NUM1 EQU 0x5A
NUM2 EQU 0x39
REG1 EQU 0x40
REG2 EQU 0x41
; =======================================================================
__CONFIG 0X3FF2
ORG 0X0000
GOTO START
ORG 0X0004
RETFIE
START BSF STATUS,RP0
MOVWF TRISB
BCF STATUS,RP0
MOVWF PORTB
BTFSC PORTA,0 ;skip next instruction if RA0 = 1 and go to SUM
GOTO SUM
MOVLW NUM2 ;put NUM2 in W
SUBLW NUM1 ;subtract NUM2 in W from NUM1
MOVWF REG1 ;save the result in REG1
MOVF STATUS,W ;copy the STATUS register value to W
MOVWF REG2 ;and then to REG2
GOTO DONE
SUM MOVLW NUM1 ;put NUM1 in W
ADDLW NUM2 ;add NUM2 with the result in W
MOVWF REG1 ;save the result in REG1
MOVF STATUS,W ;copy the STATUS register value to W
MOVWF REG2 ;and then to REG2
DONE
END
