Z80 cleanup

src/zvm_m65/z80_reset.s

@@ -0,0 +1,38 @@
+
+;
+; Z80 CPU reset
+;
+
+
+Z80_reset:
+
+	; Reset registers and internal emulation data
+	
+	lda #$00
+	tay
+@1:
+	sta z80_cpustate__start, y
+	iny
+	cmp #(z80_cpustate__end - z80_cpustate__start + 1)
+	bne @1
+
+	dew REG_AF               ; AF and SP have $FFFF value at start
+	dew REG_SP
+
+	lda TIME+2               ; give a little initial randomness to register R
+	sta REG_R06
+
+	; The engine requires all the Z80 visible memory to be present within the 1st 16MB,
+	; so set the most significant buytes of 32-bit pointers to 0.
+
+	stz REG_BC_EXT1+1
+	stz REG_DE_EXT1+1
+	stz REG_HL_EXT1+1
+	stz REG_SP_EXT1+1
+	stz REG_PC_EXT1+1
+	stz PTR_IXY_d_EXT1+1
+	stz PTR_DATA_EXT1+1
+
+	; Default bank is 1 (the fastest, continuous memory)	
+
+	jmp ZVM_set_bank_1