84PCE:OS:VAT
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Revision as of 14:00, 9 September 2015 by MateoConLechuga (Talk | contribs)
The VAT has remained pretty much the same, as has the structure of archived variables.
One important thing to note is that the ROM page offset is now a part of the whole address, which is nice in order to maintain backwards compatibility.
Traversing the VAT Example:
;------------------------------------- ; fdetect ; detects appvars, prot progs, and ; progs given a 0-terminated string ; pointed to by ix. ;------------------------------------- ; INPUTS: ; hl->place to start searching ; ix->string to find ; ; OUTPUTS: ; hl->place stopped searching ; de->program data ; bc=program size ; OP1 contains the name and type byte ; z flag set if found ;------------------------------------- fdetect: ld de,(ptemp) call _cphlde ld a,(hl) ld (typeByte_SMC),a jr nz,fcontinue inc a ret fcontinue: push hl cp appvarobj jr z,fgoodtype cp protprogobj jr z,fgoodtype cp progobj jr nz,fskip fgoodtype: dec hl dec hl dec hl ld e, (hl) dec hl ld d,(hl) dec hl ld a,(hl) call _SetDEUToA push de pop hl cp $D0 jr nc,finRAM push ix push de push hl pop ix ld a,10 add a,(ix+9) ld de,0 ld e,a add hl,de ex (sp),hl add hl,de pop de ex de,hl pop ix finRAM: inc de inc de ld bc,0 ld c,(hl) inc hl ld b,(hl) inc hl ; hl -> data push bc ; bc = size push ix pop bc fchkstr: ld a,(bc) or a,a jr z,ffound cp (hl) inc bc inc de inc hl jr z,fchkstr pop bc fskip: pop hl call fbypassname jr fdetect ffound: push bc pop hl push ix pop bc or a,a sbc hl,bc push hl pop bc pop hl ; size or a,a sbc hl,bc push hl pop bc pop hl ; current search location push bc call fbypassname pop bc xor a ret fbypassname: push de ld bc,-6 add hl,bc ld de,OP1 push de ld b,(hl) ; Name to OP1 -> For things like archiving/deleting inc b fbypassnameloop: ld a,(hl) ld (de),a inc de dec hl djnz fbypassnameloop xor a ld (de),a typeByte_SMC: =$+1 ld a,15h pop de ld (de),a pop de ret