moppre Z80 opcodes implemented

2020-12-18 18:04:19 +01:00
1 parent 345e471cae
commit bf1eb88342
@@ -0,0 +1,162 @@
+
+;
+; Z80 arithmetic instructions, 8 bit
+;
+
+; XXX put ADD instructions here
+; XXX put SUB instructions here
+; XXX put SBC instructions here
+; XXX put AND instructions here
+; XXX put OR instructions here
+; XXX put XOR instructions here
+; XXX put CP instructions here
+
+Z80_instr_04:      ; INC B
+
+	ldx REG_B
+	inc REG_B
+	bra Z80_common_INC
+
+Z80_instr_0C:      ; INC C
+
+	ldx REG_C
+	inc REG_C
+	bra Z80_common_INC
+
+Z80_instr_14:      ; INC D
+
+	ldx REG_D
+	inc REG_D
+	bra Z80_common_INC
+
+Z80_instr_1C:      ; INC E
+
+	ldx REG_E
+	inc REG_E
+	bra Z80_common_INC
+
+Z80_instr_24:      ; INC H
+
+	ldx REG_H
+	inc REG_H
+	bra Z80_common_INC
+
+Z80_instr_2C:      ; INC L
+
+	ldx REG_L
+	inc REG_L
+	bra Z80_common_INC
+
+Z80_instr_3C:      ; INC A
+
+	ldx REG_A
+	inc REG_A
+
+	; FALLTROUGH
+
+Z80_common_INC:
+
+	lda REG_F
+	and #(0xFF - Z80_SF - Z80_ZF - Z80_HF - Z80_VF - Z80_NF)
+	ora z80_ftable_INC, x
+	sta REG_F
+	rts
+
+Z80_instr_34:      ; INC (HL)
+
+	jsr (VEC_fetch_via_HL)
+	tax
+	inc
+	jsr ZVM_store_back
+	bra Z80_common_INC
+
+Z80_instr_DD_34:   ; INC (IX+d)
+
+	jsr (VEC_fetch_via_IX_d)
+	tax
+	inc
+	jsr ZVM_store_back
+	bra Z80_common_INC
+
+Z80_instr_FD_34:   ; INC (IY+d)
+
+	jsr (VEC_fetch_via_IY_d)
+	tax
+	inc
+	jsr ZVM_store_back
+	bra Z80_common_INC
+
+Z80_instr_05:      ; DEC B
+
+	ldx REG_B
+	dec REG_B
+	bra Z80_common_DEC
+
+Z80_instr_0D:      ; DEC C
+
+	ldx REG_C
+	dec REG_C
+	bra Z80_common_DEC
+
+Z80_instr_15:      ; DEC D
+
+	ldx REG_D
+	dec REG_D
+	bra Z80_common_DEC
+
+Z80_instr_1D:      ; DEC E
+
+	ldx REG_E
+	dec REG_E
+	bra Z80_common_DEC
+
+Z80_instr_25:      ; DEC H
+
+	ldx REG_H
+	dec REG_H
+	bra Z80_common_DEC
+
+Z80_instr_2D:      ; DEC L
+
+	ldx REG_L
+	dec REG_L
+	bra Z80_common_DEC
+
+Z80_instr_3D:      ; DEC A
+
+	ldx REG_A
+	dec REG_A
+
+	; FALLTROUGH
+
+Z80_common_DEC:
+
+	lda REG_F
+	and #(0xFF - Z80_SF - Z80_ZF - Z80_HF - Z80_VF - Z80_NF)
+	ora z80_ftable_DEC, x
+	sta REG_F
+	rts
+
+Z80_instr_35:      ; DEC (HL)
+
+	jsr (VEC_fetch_via_HL)
+	tax
+	dec
+	jsr ZVM_store_back
+	bra Z80_common_DEC
+
+Z80_instr_DD_35:   ; DEC (IX+d)
+
+	jsr (VEC_fetch_via_IX_d)
+	tax
+	dec
+	jsr ZVM_store_back
+	bra Z80_common_DEC
+
+Z80_instr_FD_35:   ; DEC (IY+d)
+
+	jsr (VEC_fetch_via_IY_d)
+	tax
+	dec
+	jsr ZVM_store_back
+	bra Z80_common_DEC