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Length: 1280 (0x500)
Types: TextFile
Names: »BN2BCD.MAC«
└─⟦01b5c9619⟧ Bits:30005906 Microsoft Multiplan v1.05 og HELP
└─ ⟦this⟧ »BN2BCD.MAC«
; ; ; Title Binary to BCD conversion ; Name: BN2BCD ; ; ; Purpose: Convert one byte of binary data to two ; bytes of BCD data ; ; Entry: Register A = binary data ; ; Exit: Register H = High byte of BCD data ; Register L = Low byte of BCD data ; ; Register used: AF,C,HL ; ; Time: 497 cycles maximum ; ; Size: Program 27 bytes ; ; ; BN2BCD: ;CALCULATE 100'S DIGIT - DIVIDE BY 100 ; H = QUOTIENT ; A = REMAINDER ld h,0ffh ;Start quotient at -1 D100LP: inc h ;Add 1 to quotient sub 100 ;Subtract 100 jr nc,D100LP ;Jump if difference still positive add a,100 ;Add the last 100 back ;CALCULATE 10'S AND 1'S DIGITS ; DIVIDE REMAINDER OF THE 100'S DIGIT BY 10 ; L = 10'S DIGIT ; A = 1 'S DIGIT ld l,0ffh ;Start quotient at -1 D10LP: inc l ;Add 1 to quotient sub 10 ;Subtract 10 jr nc,D10LP ;Jump if differnce still positive add a,10 ;Add the last 10 back ;Combine 1's and 10's digits ld c,a ;Save 1's digit in C ld a,l rlca ;Move 10's to high nibble of a rlca rlca rlca or c ;Or in the 1's digit ;Return with L = Low byte, H = High byte ld l,a ret «eof»