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avra: add CALL and JMP

This commit is contained in:
Virgil Dupras 2019-12-22 15:54:46 -05:00
parent 10b925e0e0
commit f54e10f9fd
3 changed files with 30 additions and 6 deletions

View File

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

View File

@ -19,3 +19,5 @@ sbis 22, 5
ser r19
bset 4
bclr 7
call foo
jmp bar

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