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Length: 1152 (0x480)
Types: TextFile
Names: »MPDADD.MAC«
└─⟦01b5c9619⟧ Bits:30005906 Microsoft Multiplan v1.05 og HELP
└─ ⟦this⟧ »MPDADD.MAC«
; ; ; Title Multiple-Precision Decimal Addition ; Name: MPDADD ; ; ; Purpose: Add 2 arrays of BCD bytes ; array1 = array1 + array2 ; ; Entry: Register pair HL = Base address of array 1 ; Register pair DE = Base address of array 2 ; Register B = Lenght of arrays in bytes ; ; The arrays are unsigned BCD numbers with a ; maximum lenght of 255 bytes, ARRAYÆ0Å is the ; least significant byte, and ARRAYÆLENGHT-1Å ; the most significant byte. ; ; Exit: Array1 := array1 + array2 ; ; Registers used: AF,B,DE,HL ; ; Time: 50 cycles per byte plus 18 cycles overhead ; ; Size: Program 12 bytes ; ; ; MPDADD: ;Test array lenght for zero, clear carry ld a,b or a ;Test lenght and clear carry ret z ;Exit if lenght is 0 ;Add operands 2 digits at a time ; Note carry is 0 initialy loop: ld a,(de) adc a,(hl) ;Add next byte daa ;Change to decimal ld (hl),a ;Store sum inc de ;Increment pointers inc hl djnz loop ;Continue until all bytes summed ret «eof»