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more boring opcodes work

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FeralChild64 authored and FeralChild64 committed 2021-01-26 00:03:07 +01:00
1 parent 1a7491483f
commit 790807c369
6 files changed
+430 -155
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src/zvm_m65/zvm_core.s
+2 -83
View File
@@ -3,38 +3,6 @@
; Z80 Virtual Machine core routines
;
!addr REG_A = $02 ; 8-bit accumulator
!addr REG_F = $03 ; 8-bit flag register
!addr REG_B = $04 ; general purpose 8-bit registers
!addr REG_C = $05
!addr REG_D = $06
!addr REG_E = $07
!addr REG_H = $08
!addr REG_L = $09
!addr REG_A_SH = $0A ; shadow registers
!addr REG_F_SH = $0B
!addr REG_B_SH = $0C
!addr REG_C_SH = $0D
!addr REG_D_SH = $0E
!addr REG_E_SH = $0F
!addr REG_H_SH = $10
!addr REG_L_SH = $11
!addr REG_IX = $12 ; 16-bit index register
!addr REG_IY = $14 ; 16-bit index register
!addr REG_SP = $16 ; 16-bit stack pointer
!addr REG_PC = $18 ; 16-bit program counter
!addr REG_I = $1A ; 8-bit interrupt vector base
!addr REG_R06 = $1B ; refresh counter, bits 0-6 (bit 7 is garbage)
!addr REG_R7 = $1C ; refresh counter, bit 7 (bits 0-6 are 0's)
!addr VEC_fetch_opcode = $1D
!addr VEC_fetch_via_HL = $1F
!addr VEC_store_via_HL = $21
ZVM_entry:
jsr ZVM_init
@@ -56,39 +24,13 @@ ZVM_init:
; XXX what is the initial SP value?
; XXX clean memory
; FALLTROUGH
jmp ZVM_set_bank_0
ZVM_bank_0:
lda #<ZVM_fetch_instr_bank_0
sta VEC_fetch_opcode+0
lda #>ZVM_fetch_instr_bank_0
sta VEC_fetch_opcode+1
rts
ZVM_bank_1:
lda #<ZVM_fetch_instr_bank_1
sta VEC_fetch_opcode+0
lda #>ZVM_fetch_instr_bank_1
sta VEC_fetch_opcode+1
rts
ZVM_fetch_opcode_bank_0:
; XXX implement, should return byte in .A
ZVM_fetch_opcode_bank_1:
; XXX implement, should return byte in .A
ZVM_run:
; CPU main loop
jsr (VEC_fetch_instr)
jsr (VEC_fetch_opcode)
asl
bcs @1
@@ -102,18 +44,6 @@ ZVM_run:
;
; Not implemented yet - XXX implement them!
;
@@ -123,15 +53,12 @@ Z80_instr_02: ; LD (BC),A
Z80_instr_03: ; INC BC
Z80_instr_04: ; INC B
Z80_instr_05: ; DEC B
Z80_instr_06: ; LD B,n
Z80_instr_07: ; RLCA
Z80_instr_08: ; EX AF,AF''
Z80_instr_09: ; ADD HL,BC
Z80_instr_0A: ; LD A,(BC)
Z80_instr_0B: ; DEC BC
Z80_instr_0C: ; INC C
Z80_instr_0D: ; DEC C
Z80_instr_0E: ; LD C,n
Z80_instr_0F: ; RRCA
Z80_instr_10: ; DJNZ e
Z80_instr_11: ; LD DE,nn
@@ -139,7 +66,6 @@ Z80_instr_12: ; LD (DE),A
Z80_instr_13: ; INC DE
Z80_instr_14: ; INC D
Z80_instr_15: ; DEC D
Z80_instr_16: ; LD D,n
Z80_instr_17: ; RLA
Z80_instr_18: ; JR e
Z80_instr_19: ; ADD HL,DE
@@ -147,7 +73,6 @@ Z80_instr_1A: ; LD A,(DE)
Z80_instr_1B: ; DEC DE
Z80_instr_1C: ; INC E
Z80_instr_1D: ; DEC E
Z80_instr_1E: ; LD E,n
Z80_instr_1F: ; RRA
Z80_instr_20: ; JR NZ,e
Z80_instr_21: ; LD HL,nn
@@ -155,7 +80,6 @@ Z80_instr_22: ; LD (nn),HL
Z80_instr_23: ; INC HL
Z80_instr_24: ; INC H
Z80_instr_25: ; DEC H
Z80_instr_26: ; LD H,n
Z80_instr_27: ; DAA
Z80_instr_28: ; JR Z,e
Z80_instr_29: ; ADD HL,HL
@@ -163,7 +87,6 @@ Z80_instr_2A: ; LD HL,(nn)
Z80_instr_2B: ; DEC HL
Z80_instr_2C: ; INC L
Z80_instr_2D: ; DEC L
Z80_instr_2E: ; LD L,n
Z80_instr_2F: ; CPL
Z80_instr_30: ; JR NC,e
Z80_instr_31: ; LD SP,nn
@@ -171,7 +94,6 @@ Z80_instr_32: ; LD (nn),A
Z80_instr_33: ; INC SP
Z80_instr_34: ; INC (HL)
Z80_instr_35: ; DEC (HL)
Z80_instr_36: ; LD (HL),n
Z80_instr_37: ; SCF
Z80_instr_38: ; JR C,e
Z80_instr_39: ; ADD HL,SP
@@ -179,7 +101,6 @@ Z80_instr_3A: ; LD A,(nn)
Z80_instr_3B: ; DEC SP
Z80_instr_3C: ; INC A
Z80_instr_3D: ; DEC A
Z80_instr_3E: ; LD A,n
Z80_instr_3F: ; CCF
Z80_instr_76: ; HALT
Z80_instr_80: ; ADD A,B
@@ -271,7 +192,6 @@ Z80_instr_D5: ; PUSH DE
Z80_instr_D6: ; SUB n
Z80_instr_D7: ; RST 10H
Z80_instr_D8: ; RET C
Z80_instr_D9: ; EXX
Z80_instr_DA: ; JP C,nn
Z80_instr_DB: ; IN A,(n)
Z80_instr_DC: ; CALL C,nn
@@ -289,7 +209,6 @@ Z80_instr_E7: ; RST 20H
Z80_instr_E8: ; RET PE
Z80_instr_E9: ; JP (HL)
Z80_instr_EA: ; JP PE,nn
Z80_instr_EB: ; EX DE,HL
Z80_instr_EC: ; CALL PE,nn
Z80_instr_ED: ; #ED
Z80_instr_EE: ; XOR n