--- M6502/M6502.pm	2007/07/30 17:56:13	30
+++ M6502/M6502.pm	2007/07/31 09:37:01	42
@@ -5,6 +5,8 @@
 
 use Data::Dump qw/dump/;
 use Carp qw/confess/;
+use Exporter 'import';
+our @EXPORT = qw'@mem $PC $A $P $X $Y $S $IPeriod $run_for';
 
 =head1 NAME
 
@@ -24,6 +26,8 @@
 our ( $A, $P, $X, $Y, $S ) = (0) x 5;
 # Set IPeriod to number of CPU cycles between calls to Loop6502
 our $IPeriod = 1;
+# Exec6502 cycles
+our $run_for = 0;
 
 =head1 init
 
@@ -32,8 +36,9 @@
 =cut
 
 sub init {
-	warn "inside init\n";
-	print "stdout\n";
+	my $self = shift;
+	warn dump(@_);
+	warn "inside init low-level M6502 from $self\n";
 };
 
 =head2 read
@@ -67,7 +72,8 @@
 
 =head2 poke_code
 
-Write series of bytes into memory without passing through MMU
+Write series of bytes into memory passing through MMU (C<read> and C<write>)
+functions. If you don't want to trigger MMU, use C<write_chunk>.
 
   $emu->poke_code( 0xbeef, 0xff, 0x00, 0xff, 0x00, 0xaa );
 
@@ -77,7 +83,22 @@
 	my $self = shift;
 	my $addr = shift;
 	warn sprintf("# poke_code(%04x,%s)\n", $addr, dump( @_ )) if $self->debug;
-	$mem[$addr++] = $_ foreach @_;
+	#$mem[$addr++] = $_ foreach @_;
+	$self->write($addr++, $_) foreach @_;
+}
+
+=head2 write_chunk
+
+Low-level update of memory, overriding user specified MMU functions C<read> and C<write>
+
+  $emu->write_chunk( $address, $chunk_of_data );
+
+=cut
+
+sub write_chunk {
+	my ($self, $addr, $chunk) = @_;
+	my $len = length($chunk);
+	splice @mem, $addr, $len, unpack('C*', $chunk);
 }
 
 =head2 ram
@@ -91,13 +112,49 @@
 sub ram {
 	my $self = shift;
 	my ($from,$to) = @_;
+	warn "ram($from,$to)\n";
 	if ($from + $to) {
 		printf "ram %04x - %04x\n", $from, $to;
-		return $mem[$from .. $to - 1];
+		return @mem[$from .. $to - 1];
 	}
 	printf "ram %04x\n", $from;
 	return $mem[$from] if defined($from);
 	confess "no from address";
 }
 
+=head2 prompt
+
+Call this after C<< $run_for >> cycles have been run on processor
+
+=cut
+
+sub prompt {
+	warn "prompt -- you should override this\n";
+	return 1;
+}
+
+=head2 push_R
+
+called by C<perl.c> to push changes in registars back to perl variables
+
+=cut
+
+sub push_R {
+	warn "push_R(",dump(@_),")\n";
+	my ( $a, $p, $x, $y, $s, $pc ) = @_;
+	$PC = $pc;
+	$S=$s; $X=$x; $Y=$y; $P=$p; $A=$a;
+	dump_R();
+}
+
+=head2 dump_R
+
+helper function which dumps registers
+
+=cut
+
+sub dump_R {
+	warn sprintf("PC: %04x A:%02x P:%02x X:%02x Y:%02x S:%02x\n", $PC, $A, $P, $X, $Y, $S);
+}
+
 1;