External Levels/Files

Tue, 12 Mar 2013 04:29:37 +0000

For your code accessing the files, here is some code that might be useful:

 ld hl,Name rst rMov9ToOP1 bcall(_ChkFindSym) jr c,FileNotFound ld a,b ld b,0 or a jr z,SizeBytes add hl,bc ld c,10 add hl,bc jp m,SizeBytes inc a ld h,40h SizeBytes: ;at this point, A is the flash page the data is on (or 0 if in RAM) ;HL points to the size bytes

Now from here, you have two options. If you are working from an App, you will probably either want to copy archive reading code to RAM, or use a bcall like _FlashToRAM or _FlashToRAM2. If it is a program in RAM, I would combine it all like this:

 ld hl,Name rst rMov9ToOP1 bcall(_ChkFindSym) jr c,FileNotFound in a,(6) push af ;save the current flash page ld a,b ld b,0 or a jr z,SizeBytes add hl,bc ld c,10 add hl,bc jp m,SizeBytes inc a ld h,40h SizeBytes: out (6),a ld c,(hl) inc l call z,AdjustAHL ld b,(hl) inc l call z,AdjustAHL ex (sp),hl ld l,a ld a,h out (6),a ld a,l pop hl ;now AHL points to the variable data, BC is the size of the data ;You can either copy the rest of the data to a temp variable or to saferam, or whatever, but the original variable can remain archived or unarchived <>

And the call AdjustAHL would be this:

 inc h ret m inc a out (6),a ld hl,40h ret

And you could similarly create your own archive reading routine:

ReadArc: ;Inputs: ; A is the flash page on which to read (or 0 if in RAM) ; HL points to the data to read ; DE points to where to copy the data ; BC is the number of bytes to copy ;Outputs: ; BC is 0 or a jr nz,FlashPageRead ld a,b or c ret z ldir ret FlashPageRead: push hl ld l,a ld a,b or c jr z,Pop1Exit in a,(6) ld h,a ld a,l ex (sp),hl out (6),a ArcReadLoop: ldi jp po,ExitArcRead bit 7,h jr nz,ArcReadLoop ld h,40h inc a out (6),a jp ArcReadLoop ;JP is one byte larger than JR, but 2 t-states faster ExitArcRead: pop af out (6),a ret Pop1Exit: pop hl ret

Also, sorry if that code is broken, I am really tired at the moment.

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External Levels/Files