28 lines
556 B
ArmAsm
28 lines
556 B
ArmAsm
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;;
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;; Official Kernal routine, described in:
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;;
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;; - [RG64] C64 Programmer's Reference Guide - page 275
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;; - [CM64] Compute's Mapping the Commodore 64 - page 229
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;;
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;; CPU registers that has to be preserved (see [RG64]): .Y
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;;
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chkin:
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;; Implemented according to 'C64 Programmers Reference Guide', page 277
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;; First retrieve the FAT/LAT/SAT table index (and check if file is open)
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; txa
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; jsr find_fls
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; bcs kernalerror_FILE_NOT_OPEN
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;; Now we have table index in Y - check if file is open for reading
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;; XXX continue implementation
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rts
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