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avra: add CALL and JMP
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@ -112,6 +112,13 @@ instrNames:
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.db "SBI", 0
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.db "SBIC", 0
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.db "SBIS", 0
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; 32-bit
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; ZASM limitation: CALL and JMP constants are 22-bit. In ZASM, we limit
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; ourselves to 16-bit. Supporting 22-bit would incur a prohibitive complexity
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; cost. As they say, 64K words ought to be enough for anybody.
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.equ I_CALL 94
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.db "CALL", 0
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.db "JMP", 0
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.db 0xff
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; Instruction table
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@ -219,6 +226,9 @@ instrTbl:
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.db 0x09, 0b10011010, 0x00 ; SBI A, b
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.db 0x09, 0b10011001, 0x00 ; SBIC A, b
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.db 0x09, 0b10011011, 0x00 ; SBIS A, b
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; k(16) (well, k(22)...)
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.db 0x08, 0b10010100, 0b00001110 ; CALL k
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.db 0x08, 0b10010100, 0b00001100 ; JMP k
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; Same signature as getInstID in instr.asm
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; Reads string in (HL) and returns the corresponding ID (I_*) in A. Sets Z if
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@ -280,7 +290,7 @@ parseInstruction:
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push hl \ pop ix ; IX is now our tblrow
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ld hl, 0
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or a
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jr z, .spit ; No arg? spit right away
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jp z, .spit ; No arg? spit right away
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and 0xf ; lower nibble
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dec a ; argspec index is 1-based
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ld hl, argSpecs
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@ -312,12 +322,18 @@ parseInstruction:
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jr c, .spitRdK8
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cp I_CBI
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jr c, .spitk12
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; spit A(5) + bit
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cp I_CALL
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jr c, .spitA5Bit
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; Spit k(16)
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call .spit ; spit 16-bit const upcode
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; divide HL by 2 (PC deals with words, not bytes)
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srl h \ rr l
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; spit 16-bit K, LSB first
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ld a, l
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call ioPutB
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ld a, h
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rla \ rla \ rla
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or l
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ld c, a
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jr .spit
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jp ioPutB
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.spitRegular:
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; Regular process which places H and L, ORring it with upcode. Works
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; in most cases.
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@ -354,6 +370,12 @@ parseInstruction:
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and 0xf
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ld b, a
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jr .spit
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.spitA5Bit:
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ld a, h
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sla a \ rla \ rla
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or l
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ld c, a
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jr .spit
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.spit:
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; LSB is spit *before* MSB
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@ -19,3 +19,5 @@ sbis 22, 5
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ser r19
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bset 4
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bclr 7
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call foo
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jmp bar
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