39 lines
808 B
ArmAsm
39 lines
808 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 281
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// - [CM64] Compute's Mapping the Commodore 64 - page 230
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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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clall_real:
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// Store .Y register
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tya
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pha
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// Original routine probably just sets LDTND to 0, but this is not really safe,
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// so we actually close all the channels; at least IDE64 does the same for
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// it's channels, see CLALL description in the IDE64 User's Guide
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!:
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ldy LDTND
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beq !+
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dey
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lda LAT, y
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jsr JCLOSE
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jmp !-
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!:
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// Restore .Y register
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pla
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tay
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// 'C64 Programmers Reference Guide', page 281, claims it calls CLRCHN too
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jsr CLRCHN
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// Not sure whether original Kernal does so, but it seems sane to also clear possible errors
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jmp kernalstatus_reset
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