64 lines
1.1 KiB
NASM
64 lines
1.1 KiB
NASM
; *** CONSTS ***
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D_DB .equ 0x00
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D_BAD .equ 0xff
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; *** CODE ***
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; 4 bytes per row, fill with zero
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directiveNames:
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.db ".DB", 0
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; This is a list of handlers corresponding to indexes in directiveNames
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directiveHandlers:
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.dw handleDB
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handleDB:
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push de
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push hl
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call toWord
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ld de, scratchpad
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ld a, 8
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call readWord
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ld hl, scratchpad
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call parseNumber
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ld a, ixl
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ld (direcData), a
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ld a, 1
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pop hl
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pop de
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ret
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; Reads string in (HL) and returns the corresponding ID (D_*) in A. Sets Z if
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; there's a match.
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getDirectiveID:
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push bc
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push de
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ld b, 1
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ld c, 4
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ld de, directiveNames
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call findStringInList
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pop de
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pop bc
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ret
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; Parse directive specified in A (D_* const) with args in (HL) and act in
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; an appropriate manner. If the directive results in writing data at its
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; current location, that data is in (direcData) and A is the number of bytes
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; in it.
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parseDirective:
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push de
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; double A to have a proper offset in directiveHandlers
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add a, a
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ld de, directiveHandlers
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call JUMP_ADDDE
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ld ixh, d
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ld ixl, e
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pop de
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jp (ix)
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; *** Variables ***
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direcData:
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.fill 2
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