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881 lines
21 KiB
NASM
881 lines
21 KiB
NASM
#include "user.inc"
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; *** Consts ***
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; Number of rows in the argspec table
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ARGSPEC_TBL_CNT .equ 28
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; Number of rows in the primary instructions table
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INSTR_TBL_CNT .equ 77
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; size in bytes of each row in the primary instructions table
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INSTR_TBL_ROWSIZE .equ 9
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; *** Code ***
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.org USER_CODE
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call parseLine
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ld b, 0
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ld c, a ; written bytes
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ld hl, curUpcode
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call copy
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ret
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unsetZ:
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push bc
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ld b, a
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inc b
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cp b
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pop bc
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ret
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; run RLA the number of times specified in B
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rlaX:
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; first, see if B == 0 to see if we need to bail out
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inc b
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dec b
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ret z ; Z flag means we had B = 0
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.loop: rla
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djnz .loop
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ret
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; Copy BC bytes from (HL) to (DE).
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copy:
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; first, let's see if BC is zero. if it is, we have nothing to do.
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; remember: 16-bit inc/dec don't modify flags. that's why we check B
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; and C separately.
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inc b
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dec b
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jr nz, .proceed
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inc c
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dec c
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ret z ; zero? nothing to do
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.proceed:
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push bc
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push de
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push hl
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ldir
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pop hl
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pop de
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pop bc
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ret
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; If string at (HL) starts with ( and ends with ), "enter" into the parens
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; (advance HL and put a null char at the end of the string) and set Z.
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; Otherwise, do nothing and reset Z.
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enterParens:
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ld a, (hl)
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cp '('
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ret nz ; nothing to do
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push hl
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ld a, 0 ; look for null char
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; advance until we get null
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.loop:
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cpi
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jp z, .found
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jr .loop
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.found:
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dec hl ; cpi over-advances. go back to null-char
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dec hl ; looking at the last char before null
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ld a, (hl)
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cp ')'
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jr nz, .doNotEnter
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; We have parens. While we're here, let's put a null
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xor a
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ld (hl), a
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pop hl ; back at the beginning. Let's advance.
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inc hl
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cp a ; ensure Z
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ret ; we're good!
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.doNotEnter:
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pop hl
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call unsetZ
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ret
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; Checks whether A is 'N' or 'M'
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checkNOrM:
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cp 'N'
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ret z
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cp 'M'
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ret
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; Parse the decimal char at A and extract it's 0-9 numerical value. Put the
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; result in A.
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;
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; On success, the carry flag is reset. On error, it is set.
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parseDecimal:
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; First, let's see if we have an easy 0-9 case
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cp '0'
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ret c ; if < '0', we have a problem
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cp '9'+1
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; We are in the 0-9 range
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sub a, '0' ; C is clear
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ret
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; Parses the string at (HL) and returns the 16-bit value in IX.
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; As soon as the number doesn't fit 16-bit any more, parsing stops and the
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; number is invalid. If the number is valid, Z is set, otherwise, unset.
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; If (HL) contains a number inside parens, we properly enter into it.
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; Upon successful return, A is set to 'N' for a parens-less number, 'M' for
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; a number inside parens.
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parseNumber:
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push hl
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push de
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push bc
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; Let's see if we have parens and already set the A result in B.
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ld b, 'N' ; if no parens
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call enterParens
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jr nz, .noparens
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ld b, 'M' ; we have parens and entered it.
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.noparens:
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ld ix, 0
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.loop:
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ld a, (hl)
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cp 0
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jr z, .end ; success!
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call parseDecimal
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jr c, .error
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; Now, let's add A to IX. First, multiply by 10.
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ld d, ixh ; we need a copy of the initial copy for later
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ld e, ixl
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add ix, ix ; x2
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add ix, ix ; x4
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add ix, ix ; x8
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add ix, de ; x9
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add ix, de ; x10
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add a, ixl
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jr nc, .nocarry
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inc ixh
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.nocarry:
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ld ixl, a
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; We didn't bother checking for the C flag at each step because we
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; check for overflow afterwards. If ixh < d, we overflowed
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ld a, ixh
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cp d
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jr c, .error ; carry is set? overflow
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inc hl
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jr .loop
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.error:
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call unsetZ
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.end:
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ld a, b
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pop bc
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pop de
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pop hl
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ret
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; Sets Z is A is ';', CR, LF, or null.
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isLineEnd:
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cp ';'
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ret z
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cp 0
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ret z
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cp 0x0d
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ret z
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cp 0x0a
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ret
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; Sets Z is A is ' ' or ','
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isSep:
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cp ' '
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ret z
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cp ','
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ret
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; Sets Z is A is ' ', ',', ';', CR, LF, or null.
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isSepOrLineEnd:
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call isSep
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ret z
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call isLineEnd
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ret
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; read word in (HL) and put it in (DE), null terminated, for a maximum of A
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; characters. As a result, A is the read length. HL is advanced to the next
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; separator char.
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readWord:
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push bc
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ld b, a
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.loop:
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ld a, (hl)
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call isSepOrLineEnd
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jr z, .success
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call JUMP_UPCASE
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ld (de), a
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inc hl
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inc de
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djnz .loop
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.success:
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xor a
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ld (de), a
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ld a, 4
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sub a, b
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jr .end
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.error:
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xor a
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ld (de), a
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.end:
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pop bc
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ret
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; (HL) being a string, advance it to the next non-sep character.
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; Set Z if we could do it before the line ended, reset Z if we couldn't.
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toWord:
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.loop:
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ld a, (hl)
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call isLineEnd
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jr z, .error
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call isSep
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jr nz, .success
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inc hl
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jr .loop
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.error:
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; we need the Z flag to be unset and it is set now. Let's CP with
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; something it can't be equal to, something not a line end.
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cp 'a' ; Z flag unset
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ret
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.success:
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; We need the Z flag to be set and it is unset. Let's compare it with
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; itself to return a set Z
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cp a
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ret
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; Read arg from (HL) into argspec at (DE)
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; HL is advanced to the next word. Z is set if there's a next word.
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readArg:
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push de
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ld de, tmpBuf
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ld a, 8
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call readWord
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push hl
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ld hl, tmpBuf
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call parseArg
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pop hl
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pop de
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ld (de), a
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; When A is a number, IX is set with the value of that number. Because
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; We don't use the space allocated to store those numbers in any other
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; occasion, we store IX there unconditonally, LSB first.
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inc de
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ld a, ixl
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ld (de), a
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inc de
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ld a, ixh
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ld (de), a
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call toWord
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ret
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; Read line from (HL) into (curWord), (curArg1) and (curArg2)
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readLine:
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push de
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xor a
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ld (curWord), a
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ld (curArg1), a
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ld (curArg2), a
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ld de, curWord
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ld a, 4
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call readWord
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call toWord
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jr nz, .end
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ld de, curArg1
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call readArg
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jr nz, .end
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ld de, curArg2
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call readArg
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.end:
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pop de
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ret
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; Returns length of string at (HL) in A.
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strlen:
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push bc
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push hl
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ld bc, 0
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ld a, 0 ; look for null char
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.loop:
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cpi
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jp z, .found
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jr .loop
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.found:
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; How many char do we have? the (NEG BC)-1, which started at 0 and
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; decreased at each CPI call. In this routine, we stay in the 8-bit
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; realm, so C only.
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ld a, c
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neg
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dec a
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pop hl
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pop bc
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ret
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; find argspec for string at (HL). Returns matching argspec in A.
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; Return value 0xff holds a special meaning: arg is not empty, but doesn't match
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; any argspec (A == 0 means arg is empty). A return value of 0xff means an
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; error.
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;
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; If the parsed argument is a number constant, 'N' is returned and IX contains
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; the value of that constant.
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parseArg:
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call strlen
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cp 0
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ret z ; empty string? A already has our result: 0
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push bc
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push de
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push hl
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ld de, argspecTbl
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; DE now points the the "argspec char" part of the entry, but what
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; we're comparing in the loop is the string next to it. Let's offset
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; DE by one so that the loop goes through strings.
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inc de
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ld b, ARGSPEC_TBL_CNT
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.loop1:
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ld a, 4
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call JUMP_STRNCMP
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jr z, .found ; got it!
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ld a, 5
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call JUMP_ADDDE
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djnz .loop1
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; We exhausted the argspecs. Let's see if it's a number. This sets
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; A to 'N' or 'M'
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call parseNumber
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jr z, .end ; Alright, we have a parsed number in IX. We're
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; done.
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; not a number
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ld a, 0xff
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jr .end
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.found:
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; found the matching argspec row. Our result is one byte left of DE.
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dec de
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ld a, (de)
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.end:
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pop hl
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pop de
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pop bc
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ret
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; Returns, with Z, whether A is a groupId
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isGroupId:
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cp 0xc ; max group id + 1
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jr nc, .notgroup ; >= 0xc? not a group
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cp 0
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jr z, .notgroup ; 0? not supposed to happen. something's wrong.
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; A is a group. ensure Z is set
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cp a
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ret
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.notgroup:
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call unsetZ
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ret
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; Find argspec A in group id H.
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; Set Z according to whether we found the argspec
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; If found, the value in A is the argspec value in the group (its index).
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findInGroup:
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push bc
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push hl
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cp 0 ; is our arg empty? If yes, we have nothing to do
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jr z, .notfound
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push af
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ld a, h
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cp 0xa
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jr z, .specialGroupCC
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cp 0xb
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jr z, .specialGroupABCDEHL
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jr nc, .notfound ; > 0xb? not a group
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pop af
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; regular group
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push de
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ld de, argGrpTbl
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; group ids start at 1. decrease it, then multiply by 4 to have a
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; proper offset in argGrpTbl
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dec h
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push af
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ld a, h
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rla
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rla
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call JUMP_ADDDE ; At this point, DE points to our group
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pop af
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ex hl, de ; And now, HL points to the group
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pop de
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ld bc, 4
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jr .find
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.specialGroupCC:
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ld hl, argGrpCC
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jr .specialGroupEnd
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.specialGroupABCDEHL:
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ld hl, argGrpABCDEHL
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.specialGroupEnd:
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pop af ; from the push af just before the special group check
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ld bc, 8
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.find:
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; This part is common to regular and special group. We expect HL to
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; point to the group and BC to contain its length.
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push bc ; save the start value loop index so we can sub
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.loop:
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cpi
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jr z, .found
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jp po, .notfound
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jr .loop
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.found:
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; we found our result! Now, what we want to put in A is the index of
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; the found argspec.
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pop hl ; we pop from the "push bc" above. L is now 4 or 8
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ld a, l
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sub c
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dec a ; cpi DECs BC even when there's a match, so C == the
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; number of iterations we've made. But our index is
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; zero-based (1 iteration == 0 index).
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cp a ; ensure Z is set
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jr .end
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.notfound:
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pop bc ; from the push bc in .find
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call unsetZ
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.end:
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pop hl
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pop bc
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ret
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; Compare argspec from instruction table in A with argument in (HL).
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; For constant args, it's easy: if A == (HL), it's a success.
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; If it's not this, then we check if it's a numerical arg.
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; If A is a group ID, we do something else: we check that (HL) exists in the
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; groupspec (argGrpTbl).
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; Set Z according to whether we match or not.
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matchArg:
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cp a, (hl)
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ret z
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; not an exact match. Before we continue: is A zero? Because if it is,
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; we have to stop right here: no match possible.
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cp 0
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jr nz, .checkIfNumber ; not a zero, we can continue
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; zero, stop here
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call unsetZ
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ret
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.checkIfNumber:
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; not an exact match, let's check for numerical constants.
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call JUMP_UPCASE
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call checkNOrM
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jr z, .expectsNumber
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jr .notNumber
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.expectsNumber:
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; Our argument is a number N or M. Never a lower-case version. At this
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; point in the processing, we don't care about whether N or M is upper,
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; we do truncation tests later. So, let's just perform the same == test
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; but in a case-insensitive way instead
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cp a, (hl)
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ret ; whether we match or not, the result of Z is
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; the good one.
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.notNumber:
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; A bit of a delicate situation here: we want A to go in H but also
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; (HL) to go in A. If not careful, we overwrite each other. EXX is
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; necessary to avoid invoving other registers.
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push hl
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exx
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ld h, a
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push hl
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exx
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ld a, (hl)
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pop hl
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call findInGroup
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pop hl
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ret
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; Compare primary row at (DE) with string at curWord. Sets Z flag if there's a
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; match, reset if not.
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matchPrimaryRow:
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push hl
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push ix
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ld hl, curWord
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ld a, 4
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call JUMP_STRNCMP
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jr nz, .end
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; name matches, let's see the rest
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ld ixh, d
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ld ixl, e
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ld hl, curArg1
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ld a, (ix+4)
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call matchArg
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jr nz, .end
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ld hl, curArg2
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ld a, (ix+5)
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call matchArg
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.end:
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pop ix
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pop hl
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ret
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; Compute the upcode for argspec row at (DE) and arguments in curArg{1,2} and
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; writes the resulting upcode in curUpcode. A is the number if bytes written
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; to curUpcode (can be zero if something went wrong).
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getUpcode:
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push ix
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push de
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push hl
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push bc
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; First, let's go in IX mode. It's easier to deal with offsets here.
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ld ixh, d
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ld ixl, e
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; we begin by writing our "base upcode", which can be one or two bytes
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ld a, (ix+7) ; first upcode
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ld (curUpcode), a
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ld de, curUpcode ; from this point, DE points to "where we are"
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; in terms of upcode writing.
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inc de ; make DE point to where we should write next.
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ld a, (ix+8) ; second upcode
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cp 0 ; do we have a second upcode?
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jr z, .onlyOneUpcode
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; we have two upcodes
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ld (de), a
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inc de
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.onlyOneUpcode:
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; now, let's see if we're dealing with a group here
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ld a, (ix+4) ; first argspec
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call isGroupId
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jr z, .firstArgIsGroup
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; First arg not a group. Maybe second is?
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ld a, (ix+5) ; 2nd argspec
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call isGroupId
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jr nz, .writeExtraBytes ; not a group? nothing to do. go to
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; next step: write extra bytes
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; Second arg is group
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ld hl, curArg2
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jr .isGroup
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.firstArgIsGroup:
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ld hl, curArg1
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.isGroup:
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; A is a group, good, now let's get its value. HL is pointing to
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; the argument. A little bit of stack gymnastic is necessary to put
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; A into H and (HL) into A.
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push af
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ld a, (hl)
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pop hl ; from push af 2 lines above
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call findInGroup ; we don't check for match, it's supposed to
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; always match. Something is very wrong if it
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; doesn't
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; Now, we have our arg "group value" in A. Were going to need to
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; displace it left by the number of steps specified in the table.
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push af
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ld a, (ix+6) ; displacement bit
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and a, 0xf ; we only use the lower nibble.
|
|
ld b, a
|
|
pop af
|
|
call rlaX
|
|
|
|
; At this point, we have a properly displaced value in A. We'll want
|
|
; to OR it with the opcode.
|
|
; However, we first have to verify whether this ORing takes place on
|
|
; the second upcode or the first.
|
|
bit 6, (ix+6)
|
|
jr z, .firstUpcode ; not set: first upcode
|
|
or (ix+8) ; second upcode
|
|
ld (curUpcode+1), a
|
|
jr .writeExtraBytes
|
|
.firstUpcode:
|
|
or (ix+7) ; first upcode
|
|
ld (curUpcode), a
|
|
jr .writeExtraBytes
|
|
.writeExtraBytes:
|
|
; Good, we are probably finished here for many primary opcodes. However,
|
|
; some primary opcodes take 8 or 16 bit constants as an argument and
|
|
; if that's the case here, we need to write it too.
|
|
; We still have our instruction row in IX and we have DE pointing to
|
|
; where we should write next (which could be the second or the third
|
|
; byte of curUpcode).
|
|
ld a, (ix+4) ; first argspec
|
|
ld hl, curArg1
|
|
call checkNOrM
|
|
jr z, .withWord
|
|
cp 'n'
|
|
jr z, .withByte
|
|
cp 'm'
|
|
jr z, .withByte
|
|
ld a, (ix+5) ; second argspec
|
|
ld hl, curArg2
|
|
call checkNOrM
|
|
jr z, .withWord
|
|
cp 'n'
|
|
jr z, .withByte
|
|
cp 'm'
|
|
jr z, .withByte
|
|
; nope, no number, alright, we're finished here
|
|
ld c, 1
|
|
jr .computeBytesWritten
|
|
.withByte:
|
|
; verify that the MSB in argument is zero
|
|
inc hl
|
|
inc hl ; MSB is 2nd byte
|
|
ld a, (hl)
|
|
dec hl ; HL now points to LSB
|
|
cp 0
|
|
jr nz, .numberTruncated
|
|
; HL points to our number
|
|
; one last thing to check. Is the 7th bit on the displacement value set?
|
|
; if yes, we have to decrease our value by 2. Uses for djnz and jr.
|
|
bit 7, (ix+6)
|
|
jr z, .skipDecrease
|
|
; Yup, it's set.
|
|
dec (hl)
|
|
dec (hl)
|
|
.skipDecrease:
|
|
ldi
|
|
ld c, 2
|
|
jr .computeBytesWritten
|
|
|
|
.withWord:
|
|
inc hl ; HL now points to LSB
|
|
; Clear to proceed. HL already points to our number
|
|
ldi ; LSB written, we point to MSB now
|
|
ldi ; MSB written
|
|
ld c, 3
|
|
jr .computeBytesWritten
|
|
.computeBytesWritten:
|
|
; At this point, everything that we needed to write in curUpcode is
|
|
; written an C is 1 if we have no extra byte, 2 if we have an extra
|
|
; byte and 3 if we have an extra word. What we need to do here is check
|
|
; if ix+8 is non-zero and increase C if it is.
|
|
ld a, (ix+8)
|
|
cp 0
|
|
jr z, .end ; no second upcode? nothing to do.
|
|
; We have 2 base upcodes
|
|
inc c
|
|
jr .end
|
|
.numberTruncated:
|
|
; problem: not zero, so value is truncated. error
|
|
xor c
|
|
.end:
|
|
ld a, c
|
|
pop bc
|
|
pop hl
|
|
pop de
|
|
pop ix
|
|
ret
|
|
|
|
; Parse line at (HL) and write resulting opcode(s) in curUpcode. Returns the
|
|
; number of bytes written in A.
|
|
parseLine:
|
|
call readLine
|
|
; Check whether we have errors. We don't do any parsing if we do.
|
|
ld a, (curArg1)
|
|
cp 0xff
|
|
jr z, .error
|
|
ret z
|
|
ld a, (curArg2)
|
|
cp 0xff
|
|
jr nz, .noerror
|
|
.error:
|
|
xor a
|
|
ret
|
|
.noerror:
|
|
push de
|
|
ld de, instrTBl
|
|
ld b, INSTR_TBL_CNT
|
|
.loop:
|
|
ld a, (de)
|
|
call matchPrimaryRow
|
|
jr z, .match
|
|
ld a, INSTR_TBL_ROWSIZE
|
|
call JUMP_ADDDE
|
|
djnz .loop
|
|
; no match
|
|
xor a
|
|
jr .end
|
|
.match:
|
|
; We have our matching instruction row. We're getting pretty near our
|
|
; goal here!
|
|
call getUpcode
|
|
.end:
|
|
pop de
|
|
ret
|
|
|
|
|
|
; In instruction metadata below, argument types arge indicated with a single
|
|
; char mnemonic that is called "argspec". This is the table of correspondance.
|
|
; Single letters are represented by themselves, so we don't need as much
|
|
; metadata.
|
|
; Special meaning:
|
|
; 0 : no arg
|
|
; 1-10 : group id (see Groups section)
|
|
; 0xff: error
|
|
|
|
; Format: 1 byte argspec + 4 chars string
|
|
argspecTbl:
|
|
.db 'A', "A", 0, 0, 0
|
|
.db 'B', "B", 0, 0, 0
|
|
.db 'C', "C", 0, 0, 0
|
|
.db 'D', "D", 0, 0, 0
|
|
.db 'E', "E", 0, 0, 0
|
|
.db 'H', "H", 0, 0, 0
|
|
.db 'L', "L", 0, 0, 0
|
|
.db 'h', "HL", 0, 0
|
|
.db 'l', "(HL)"
|
|
.db 'd', "DE", 0, 0
|
|
.db 'e', "(DE)"
|
|
.db 'b', "BC", 0, 0
|
|
.db 'c', "(BC)"
|
|
.db 'a', "AF", 0, 0
|
|
.db 'f', "AF'", 0
|
|
.db 'X', "IX", 0, 0
|
|
.db 'Y', "IY", 0, 0
|
|
.db 'x', "(IX)" ; always come with displacement
|
|
.db 'y', "(IY)" ; with JP
|
|
.db 's', "SP", 0, 0
|
|
.db 'p', "(SP)"
|
|
; we also need argspecs for the condition flags
|
|
.db 'Z', "Z", 0, 0, 0
|
|
.db 'z', "NZ", 0, 0
|
|
; C is in conflict with the C register. The situation is ambiguous, but
|
|
; doesn't cause actual problems.
|
|
.db '=', "NC", 0, 0
|
|
.db '+', "P", 0, 0, 0
|
|
.db '-', "M", 0, 0, 0
|
|
.db '1', "PO", 0, 0
|
|
.db '2', "PE", 0, 0
|
|
|
|
; argspecs not in the list:
|
|
; n -> N
|
|
; N -> NN
|
|
; m -> (N) (running out of mnemonics. 'm' for 'memory pointer')
|
|
; M -> (NN)
|
|
|
|
; Groups
|
|
; Groups are specified by strings of argspecs. To facilitate jumping to them,
|
|
; we have a fixed-sized table. Because most of them are 2 or 4 bytes long, we
|
|
; have a table that is 4 in size to minimize consumed space. We treat the two
|
|
; groups that take 8 bytes in a special way.
|
|
;
|
|
; The table below is in order, starting with group 0x01
|
|
argGrpTbl:
|
|
.db "bdha" ; 0x01
|
|
.db "ZzC=" ; 0x02
|
|
.db "bdhs" ; 0x03
|
|
.db "bdXs" ; 0x04
|
|
.db "bdYs" ; 0x05
|
|
|
|
argGrpCC:
|
|
.db "zZ=C12+-" ; 0xa
|
|
argGrpABCDEHL:
|
|
.db "BCDEHL_A" ; 0xb
|
|
|
|
; This is a list of primary instructions (single upcode) that lead to a
|
|
; constant (no group code to insert). Format:
|
|
;
|
|
; 4 bytes for the name (fill with zero)
|
|
; 1 byte for arg constant
|
|
; 1 byte for 2nd arg constant
|
|
; 1 byte displacement for group arguments + flags
|
|
; 2 bytes for upcode (2nd byte is zero if instr is one byte)
|
|
;
|
|
; The displacement bit is split in 2 nibbles: lower nibble is the displacement
|
|
; value, upper nibble is for flags. There is one flag currently, on bit 7, that
|
|
; indicates that the numerical argument is of the 'e' type and has to be
|
|
; decreased by 2 (djnz, jr). On bit 6, it indicates that the group argument's
|
|
; value is to be placed on the second upcode rather than the first.
|
|
|
|
instrTBl:
|
|
.db "ADC", 0, 'A', 'l', 0, 0x8e , 0 ; ADC A, (HL)
|
|
.db "ADC", 0, 'A', 0xb, 0, 0b10001000 , 0 ; ADC A, r
|
|
.db "ADC", 0, 'A', 'n', 0, 0xce , 0 ; ADC A, n
|
|
.db "ADC", 0,'h',0x3,0x44, 0xed, 0b01001010 ; ADC HL, ss
|
|
.db "ADD", 0, 'A', 'l', 0, 0x86 , 0 ; ADD A, (HL)
|
|
.db "ADD", 0, 'A', 0xb, 0, 0b10000000 , 0 ; ADD A, r
|
|
.db "ADD", 0, 'A', 'n', 0, 0xc6 , 0 ; ADD A, n
|
|
.db "ADD", 0, 'h', 0x3, 4, 0b00001001 , 0 ; ADD HL, ss
|
|
.db "ADD", 0,'X',0x4,0x44, 0xdd, 0b00001001 ; ADD IX, pp
|
|
.db "ADD", 0,'Y',0x5,0x44, 0xfd, 0b00001001 ; ADD IY, rr
|
|
.db "AND", 0, 'l', 0, 0, 0xa6 , 0 ; AND (HL)
|
|
.db "AND", 0, 0xb, 0, 0, 0b10100000 , 0 ; AND r
|
|
.db "AND", 0, 'n', 0, 0, 0xe6 , 0 ; AND n
|
|
.db "CALL", 0xa, 'N', 3, 0b11000100 , 0 ; CALL cc, NN
|
|
.db "CALL", 'N', 0, 0, 0xcd , 0 ; CALL NN
|
|
.db "CCF", 0, 0, 0, 0, 0x3f , 0 ; CCF
|
|
.db "CP",0,0, 'l', 0, 0, 0xbe , 0 ; CP (HL)
|
|
.db "CP",0,0, 0xb, 0, 0, 0b10111000 , 0 ; CP r
|
|
.db "CP",0,0, 'n', 0, 0, 0xfe , 0 ; CP n
|
|
.db "CPL", 0, 0, 0, 0, 0x2f , 0 ; CPL
|
|
.db "DAA", 0, 0, 0, 0, 0x27 , 0 ; DAA
|
|
.db "DI",0,0, 0, 0, 0, 0xf3 , 0 ; DI
|
|
.db "DEC", 0, 'l', 0, 0, 0x35 , 0 ; DEC (HL)
|
|
.db "DEC", 0, 0xb, 0, 3, 0b00000101 , 0 ; DEC r
|
|
.db "DEC", 0, 0x3, 0, 4, 0b00001011 , 0 ; DEC s
|
|
.db "DJNZ", 'n', 0,0x80, 0x10 , 0 ; DJNZ e
|
|
.db "EI",0,0, 0, 0, 0, 0xfb , 0 ; EI
|
|
.db "EX",0,0, 'p', 'h', 0, 0xe3 , 0 ; EX (SP), HL
|
|
.db "EX",0,0, 'a', 'f', 0, 0x08 , 0 ; EX AF, AF'
|
|
.db "EX",0,0, 'd', 'h', 0, 0xeb , 0 ; EX DE, HL
|
|
.db "EXX", 0, 0, 0, 0, 0xd9 , 0 ; EXX
|
|
.db "HALT", 0, 0, 0, 0x76 , 0 ; HALT
|
|
.db "IN",0,0, 'A', 'm', 0, 0xdb , 0 ; IN A, (n)
|
|
.db "INC", 0, 'l', 0, 0, 0x34 , 0 ; INC (HL)
|
|
.db "INC", 0, 0xb, 0, 3, 0b00000100 , 0 ; INC r
|
|
.db "INC", 0, 0x3, 0, 4, 0b00000011 , 0 ; INC s
|
|
.db "JP",0,0, 'l', 0, 0, 0xe9 , 0 ; JP (HL)
|
|
.db "JP",0,0, 'N', 0, 0, 0xc3 , 0 ; JP NN
|
|
.db "JR",0,0, 'n', 0,0x80, 0x18 , 0 ; JR e
|
|
.db "JR",0,0,'C','n',0x80, 0x38 , 0 ; JR C, e
|
|
.db "JR",0,0,'=','n',0x80, 0x30 , 0 ; JR NC, e
|
|
.db "JR",0,0,'Z','n',0x80, 0x28 , 0 ; JR Z, e
|
|
.db "JR",0,0,'z','n',0x80, 0x20 , 0 ; JR NZ, e
|
|
.db "LD",0,0, 'c', 'A', 0, 0x02 , 0 ; LD (BC), A
|
|
.db "LD",0,0, 'e', 'A', 0, 0x12 , 0 ; LD (DE), A
|
|
.db "LD",0,0, 'A', 'c', 0, 0x0a , 0 ; LD A, (BC)
|
|
.db "LD",0,0, 'A', 'e', 0, 0x1a , 0 ; LD A, (DE)
|
|
.db "LD",0,0, 's', 'h', 0, 0xf9 , 0 ; LD SP, HL
|
|
.db "LD",0,0, 'l', 0xb, 0, 0b01110000 , 0 ; LD (HL), r
|
|
.db "LD",0,0, 0xb, 'l', 3, 0b01000110 , 0 ; LD r, (HL)
|
|
.db "LD",0,0, 'l', 'n', 0, 0x36 , 0 ; LD (HL), n
|
|
.db "LD",0,0, 0xb, 'n', 3, 0b00000110 , 0 ; LD r, (HL)
|
|
.db "LD",0,0, 0x3, 'N', 4, 0b00000001 , 0 ; LD dd, n
|
|
.db "LD",0,0, 'M', 'A', 0, 0x32 , 0 ; LD (NN), A
|
|
.db "LD",0,0, 'A', 'M', 0, 0x3a , 0 ; LD A, (NN)
|
|
.db "LD",0,0, 'M', 'h', 0, 0x22 , 0 ; LD (NN), HL
|
|
.db "LD",0,0, 'h', 'M', 0, 0x2a , 0 ; LD HL, (NN)
|
|
.db "NOP", 0, 0, 0, 0, 0x00 , 0 ; NOP
|
|
.db "OR",0,0, 'l', 0, 0, 0xb6 , 0 ; OR (HL)
|
|
.db "OR",0,0, 0xb, 0, 0, 0b10110000 , 0 ; OR r
|
|
.db "OUT", 0, 'm', 'A', 0, 0xd3 , 0 ; OUT (n), A
|
|
.db "POP", 0, 0x1, 0, 4, 0b11000001 , 0 ; POP qq
|
|
.db "PUSH", 0x1, 0, 4, 0b11000101 , 0 ; PUSH qq
|
|
.db "RET", 0, 0, 0, 0, 0xc9 , 0 ; RET
|
|
.db "RET", 0, 0xa, 0, 3, 0b11000000 , 0 ; RET cc
|
|
.db "RLA", 0, 0, 0, 0, 0x17 , 0 ; RLA
|
|
.db "RLCA", 0, 0, 0, 0x07 , 0 ; RLCA
|
|
.db "RRA", 0, 0, 0, 0, 0x1f , 0 ; RRA
|
|
.db "RRCA", 0, 0, 0, 0x0f , 0 ; RRCA
|
|
.db "SBC", 0, 'A', 'l', 0, 0x9e , 0 ; SBC A, (HL)
|
|
.db "SBC", 0, 'A', 0xb, 0, 0b10011000 , 0 ; SBC A, r
|
|
.db "SCF", 0, 0, 0, 0, 0x37 , 0 ; SCF
|
|
.db "SUB", 0, 'A', 'l', 0, 0x96 , 0 ; SUB A, (HL)
|
|
.db "SUB", 0, 'A', 0xb, 0, 0b10010000 , 0 ; SUB A, r
|
|
.db "SUB", 0, 'n', 0, 0, 0xd6 , 0 ; SUB n
|
|
.db "XOR", 0, 'l', 0, 0, 0xae , 0 ; XOR (HL)
|
|
.db "XOR", 0, 0xb, 0, 0, 0b10101000 , 0 ; XOR r
|
|
|
|
|
|
; *** Variables ***
|
|
; enough space for 4 chars and a null
|
|
curWord:
|
|
.db 0, 0, 0, 0, 0
|
|
|
|
; Args are 3 bytes: argspec, then values of numerical constants (when that's
|
|
; appropriate)
|
|
curArg1:
|
|
.db 0, 0, 0
|
|
curArg2:
|
|
.db 0, 0, 0
|
|
|
|
curUpcode:
|
|
.db 0, 0, 0, 0
|
|
|
|
; space for tmp stuff
|
|
tmpBuf:
|
|
.fill 0x20
|
|
|