From 70bc8883020a2da4326439a8308513a7385dc568 Mon Sep 17 00:00:00 2001
From: Duncan Smith
Date: Mon, 6 Sep 2010 18:09:29 -0700
Subject: Fixes to actually run code

This is the version to run the first (trivial) infinite loop
correctly.  I hacked up the loader slightly to replace one of the
(nonexistent) pages with a static byte array.

z80 code executed:

$4000:
	JP	$4000

4000  c3 40 00
4003

This version also draws the opcode executed on the screen, to aid in
debugging the emulator:

        move.b  d0,$4c00+32*(128/8)

Also, it turns out that I was mixing up the emulated SP (a4) and emulated
PC (a6).  That has been fixed.

Further, it seems that movea defaults to a word operation in a68k.
This led to pointer corruption, which has been fixed.
---
 opcodes.asm | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

(limited to 'opcodes.asm')

diff --git a/opcodes.asm b/opcodes.asm
index fe5547c..8042296 100644
--- a/opcodes.asm
+++ b/opcodes.asm
@@ -108,7 +108,8 @@ _align	SET	_align+$20
 	;; This is run at the end of every instruction routine.
 DONE	MACRO
 	clr.w	d0		; 4 cycles / 2 bytes
-	move.b	(a4)+,d0	; 8 cycles / 2 bytes
+	move.b	(a6)+,d0	; 8 cycles / 2 bytes
+	move.b	d0,$4c00+32*(128/8)
 	rol.w	#5,d0		;16 cycles / 2 bytes
 	jmp	0(a5,d0.w)	;14 cycles / 4 bytes
 	;; overhead:		 42 cycles /10 bytes
@@ -602,7 +603,7 @@ emu_op_31:
 	;; LD	SP,immed.w
 	FETCHWI	d1
 	bsr	deref
-	movea	a0,a4
+	movea.l	a0,a4
 	DONE
 
 	START
@@ -1792,7 +1793,7 @@ emu_op_c3:			; S12 T36
 	;; PC <- immed.w
 	FETCHWI	d1
 	bsr	deref
-	movea	a0,a6
+	movea.l	a0,a6
 	DONE
 
 	START
@@ -1844,7 +1845,7 @@ emu_op_c9:
 	;; SP <- (SP+2)
 	POPW	d1
 	bsr	deref
-	movea	a0,a6
+	movea.l	a0,a6
 	DONE
 
 	START
@@ -2095,7 +2096,7 @@ emu_op_e9:
 	;; JP	(HL)
 	FETCHB	d6,d1
 	bsr	deref
-	movea	a0,a6
+	movea.l	a0,a6
 	DONE
 
 	START
@@ -2225,7 +2226,7 @@ emu_op_f9:
 	;; SP <- HL
 	move.w	d6,d1
 	bsr	deref
-	movea	a0,a4
+	movea.l	a0,a4
 	DONE
 
 	START
-- 
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