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;
;30h-39h hold the 7seg bit patterns
mov 30h, #11000000B
mov 31h, #11111001B
mov 32h, #10100100B
mov 33h, #10110000B
mov 34h, #10011001B
mov 35h, #10010010B
mov 36h, #10000010B
mov 37h, #10000111B
mov 38h, #10000000B
mov 39h, #10011000B
mov
start:
jmp start
;40h-42h hold the 3 digits to display
display:
mov acc, 50h
mov b, #1000
div ab
mov 40h, acc
mov acc, b
mov b, #100
div ab
mov 41h, acc; save 100's digit
mov acc, b ;put remainder in a
mov b, #10 ;find 10's & 1's digit
div ab
mov 42h, acc ;save 10's digit
mov 43h, b ;save 1's digit
;display:
mov r1, #40h ;digits[0]
loop: ;for each digit
mov acc, #30h
mov r3, acc ;save acc;next blob:
;safe if you don't care about the
;bits of P3 other than p3.3 & p3.4
mov a, r1 ;picks which
cpl a ;7seg to use p3.3 &
anl a, #03h ;p3.4 are a func
rl a ;of the low2 bits of
rl a ;the addr where the
rl a ;digits live
mov p1, #0ffh;undraw previous
mov p3, a ;set new 7seg
mov a, r3 ;restore acc
; p1 = pattern[digit[i]]
add a, @r1
mov r0, acc
mov p1, @r0
inc r1
; mov p1, #0ffh
cjne r1, #44h, loop
ret
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