42 lines
987 B
ArmAsm
42 lines
987 B
ArmAsm
; Function defined on pp272-273 of C64 Programmers Reference Guide
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close:
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;; Implemented accorging to 'C64 Programmers Reference Guide', page 281
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;; XXX this needs more testing (opening 10 files at once, closing in various orders, etc) once the code is more mature
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;; Find the LAT / SAT / FAT entry which LAT corresponds to A
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ldy LDTND
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beq close_error_not_found ; table empty
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*
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dey
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bmi close_error_not_found ; no more entries
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cmp LAT, y
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bne - ; does not match, try the next one
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;; We have the entry index in Y
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;; XXX some devices (like IEC) needs special support here, to free their internal resources!
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;; Just make sure the Y register value is kept, or redo ldy DFTLN
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*
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iny
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cpy #$0A
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bpl +
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lda LAT, y
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sta LAT-1, y
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lda FAT, y
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sta FAT-1, y
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lda SAT, y
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sta SAT-1, y
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jmp -
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*
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;; Decrement the list size variable
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dec LDTND
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;; FALLTHROUGH (for now) - success
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close_error_not_found:
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;; XXX it seems that this function can't report errors, am I right?
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rts
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