--- M6502/Orao.pm	2007/08/02 11:08:10	87
+++ M6502/Orao.pm	2007/08/02 12:01:09	89
@@ -284,6 +284,7 @@
 	my $self = shift;
 	my ($addr) = @_;
 	my $byte = $mem[$addr];
+	confess sprintf("can't find memory at address %04x",$addr);
 	warn sprintf("# Orao::read(%04x) = %02x\n", $addr, $byte) if $self->trace;
 
 	# keyboard