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zasm: add support for LD r, r' instructions

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This commit is contained in:
Virgil Dupras 2019-05-13 16:38:09 -04:00
parent 878bc2919f
commit c9deac599e
1 changed files with 17 additions and 7 deletions
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24
apps/zasm/instr.asm
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@ -2,7 +2,7 @@
; Number of rows in the argspec table
ARGSPEC_TBL_CNT .equ 31
; Number of rows in the primary instructions table
INSTR_TBL_CNT .equ 135
INSTR_TBL_CNT .equ 136
; size in bytes of each row in the primary instructions table
INSTR_TBL_ROWSIZE .equ 6
; Instruction IDs They correspond to the index of the table in instrNames
@ -493,9 +493,6 @@ handleLDIXYn:
ld (instrUpcode+3), a
ld c, 4
ret
.error:
xor c
ret
handleLDIXr:
ld a, 0xdd
@ -511,8 +508,20 @@ handleLDIXYr:
ld (instrUpcode+2), a
ld c, 3
ret
.error:
xor c
handleLDrr:
; first argument is displaced by 3 bits, second argument is not
; displaced and we or that with a leading 0b01000000
ld a, (curArg1+1) ; group value
rla
rla
rla
ld c, a ; store it
ld a, (curArg2+1) ; other group value
or c
or 0b01000000
ld (instrUpcode), a
ld c, 1
ret
; Compute the upcode for argspec row at (DE) and arguments in curArg{1,2} and
@ -1010,7 +1019,8 @@ instrTBl:
.db I_LD, 'l', 0xb, 0, 0b01110000 , 0 ; LD (HL), r
.db I_LD, 0xb, 'l', 3, 0b01000110 , 0 ; LD r, (HL)
.db I_LD, 'l', 'n', 0, 0x36 , 0 ; LD (HL), n
.db I_LD, 0xb, 'n', 3, 0b00000110 , 0 ; LD r, (HL)
.db I_LD, 0xb, 'n', 3, 0b00000110 , 0 ; LD r, n
.db I_LD, 0xb, 0xb, 0x20 \ .dw handleLDrr ; LD r, r'
.db I_LD, 0x3, 'N', 4, 0b00000001 , 0 ; LD dd, n
.db I_LD, 'M', 'A', 0, 0x32 , 0 ; LD (NN), A
.db I_LD, 'A', 'M', 0, 0x3a , 0 ; LD A, (NN)