1 REM Ins{nd av: Kristoffer Eriksson <5357> 1988-07-25 01.15.11 (WRITE) ; Fil: KERMCSUM.ASM ; Av: Kristoffer Eriksson, "SKE" <5357>, 1987. ; ;-Ver--/-Datum----/-Sign-/-Kommentar---------------------------------- ; 1.00 / 87-08-15 / SKE / KERMCSUM ; ; Kontrollsummarutin till Bo Kullmars Kermit-program K. ;* Summera str{ng f|r Kermit-kontrollsumma. ;* In: DE = VAROOT(Str{ng$) ;* Ut: L = Summa, bittar 5-0, ;* H = Summa, bittar 13-6. Csum: ex de,hl inc hl inc hl ld e,(hl) ; DE <- Str{ngens adress. inc hl ld d,(hl) inc hl ld c,(hl) ; BC <- Str{ngens l{ngd. inc hl ld b,(hl) ld hl,0 ; HL <- Startsumma = 0. Loop: ld a,c ; Slut? or b jr z CEnd ld a,(de) ; Summera. add l ld l,a ld a,0 adc h ld h,a dec bc inc de jr Loop CEnd: ld a,l rlc a rl h rlc a rl h ; H <- bit 13-6. ld a,l and 63 ld l,a ; L <- bit 5-0. ret