diff --git a/Source/HBIOS/dbgmon.asm b/Source/HBIOS/dbgmon.asm
index f5d360ef..fde7110b 100644
--- a/Source/HBIOS/dbgmon.asm
+++ b/Source/HBIOS/dbgmon.asm
@@ -38,7 +38,7 @@ ENA_XM	.EQU	FALSE			; NO ROOM FOR BOTH DSKY+XMODEM
 ENA_XM	.EQU	TRUE			; INCLUDE XMODEM IF SPACE AVAILABLE
 #ENDIF
 ;
-ENA_MBC6502	.EQU	TRUE		; ENABLE OR DISABLE MBC6502 OPTION
+ENA_MBC6502	.EQU	FALSE		; ENABLE OR DISABLE MBC6502 OPTION
 ;
 #INCLUDE "util.asm"
 ;