diff --git a/Source/HBIOS/hbios.asm b/Source/HBIOS/hbios.asm
index 46d315a7..51eeec24 100644
--- a/Source/HBIOS/hbios.asm
+++ b/Source/HBIOS/hbios.asm
@@ -1877,6 +1877,17 @@ SAVE_REC_M:
 	LD	A,0			; BIT 6
 	JR	Z,SAVE_REC_M		; IS RECOVERY MODE
 	LD	A,1
+SAVE_REC_M:
+	LD	(HB_BOOT_REC),A		; SAVE FOR LATER
+    #ENDIF
+  #ENDIF
+  #IF ((PLATFORM == PLT_DUO)
+    #IF (BT_REC_TYPE == BT_REC_DUORI)
+	IN	A,($78 + 6)		; UART_MSR MODEM
+	BIT	6,A			; STATUS REGISTER
+	LD	A,0			; BIT 6
+	JR	Z,SAVE_REC_M		; IS RECOVERY MODE
+	LD	A,1
 SAVE_REC_M:
 	LD	(HB_BOOT_REC),A		; SAVE FOR LATER
     #ENDIF
@@ -3225,7 +3236,7 @@ CALLDUMMY:
 #IF (BT_REC_TYPE != BT_REC_NONE)
 ;
 HB_PCINIT_REC:
-  #IF ((PLATFORM == PLT_SBC) | (PLATFORM == PLT_MBC))
+  #IF ((PLATFORM == PLT_SBC) | (PLATFORM == PLT_MBC) | (PLATFORM == PLT_DUO))
 	.DW	UART_PREINIT
 ;	.DW	CALLDUMMY
   #ENDIF
@@ -3237,6 +3248,10 @@ HB_INIT_REC:
 	.DW	MD_INIT
 	.DW	PPIDE_INIT
   #ENDIF
+  #IF ((PLATFORM == PLT_DUO)
+	.DW	UART_INIT
+	.DW	MD_INIT
+  #ENDIF
 HB_INITRLEN	.EQU	(($ - HB_INIT_REC) / 2)
 ;
 #ENDIF
diff --git a/Source/HBIOS/std.asm b/Source/HBIOS/std.asm
index de3ac009..6a53acbb 100644
--- a/Source/HBIOS/std.asm
+++ b/Source/HBIOS/std.asm
@@ -21,7 +21,7 @@
 ; 17. DUO	Andrew Lynch's Duodyne Computer
 ; 18. HEATH	Les Bird's Heath Z80 Board
 ; 19. EPITX	Alan Cox' Mini-ITX System
-; 20. MON	Jacques Pelletier's Monsputer
+; 20. MON	Jacques Pelletier's Monsputer
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;
@@ -87,6 +87,8 @@ BT_REC_FORCE	.EQU	1		; FORCE BOOT RECOVERY MODE
 BT_REC_SBC01	.EQU	2		; ECB-SBCV2 - BIT 1 RTC HIGH
 BT_REC_SBC1B	.EQU	3		; ECB-SBCV2 - 1-BIT IO PORT
 BT_REC_SBCRI	.EQU	4		; ECB-SBCV2 - 16550 UART RING INDICATOR LINE
+BT_REC_DUORI	.EQU	5		; DUO MULTI I/O - TL16C2552FN UART RING INDICATOR LINE
+
 ;
 BT_REC_TYPE	.EQU	BT_REC_NONE	; BOOT RECOVERY METHOD TO USE
 ;
diff --git a/Source/HBIOS/uart.asm b/Source/HBIOS/uart.asm
index eef0d133..cd8fe8fb 100644
--- a/Source/HBIOS/uart.asm
+++ b/Source/HBIOS/uart.asm
@@ -56,19 +56,17 @@ UART_CTSBAD		.EQU	4	; CTS STALL DETECTED
 ;
 #IF (PLATFORM == PLT_DUO)
 UARTSBASE		.EQU	$58
+UARTDBASE		.EQU	$70
 #ELSE
 UARTSBASE		.EQU	$68
+UARTDBASE		.EQU	$80
 #ENDIF
+;
 UARTABASE		.EQU	$A8
 UARTCBASE		.EQU	$80
 UARTMBASE		.EQU	$18
 UART4BASE		.EQU	$C0
 UARTRBASE		.EQU	$A0
-#IF (PLATFORM == PLT_DUO)
-UARTDBASE		.EQU	$70
-#ELSE
-UARTDBASE		.EQU	$80
-#ENDIF
 ;
 #IF (UARTINTS)
 ;
@@ -1165,26 +1163,25 @@ UART_CFG_MFP:
 	; DUAL UART CHANNEL A
 	.DB	0				; DEVICE NUMBER (UPDATED DURING INIT)
 	.DB	0				; UART TYPE
-	.DB	UARTDBASE			; IO PORT BASE (RBR, THR)
-	.DB	UARTDBASE + UART_LSR		; LINE STATUS PORT (LSR)
+	.DB	UARTDBASE+8			; IO PORT BASE (RBR, THR)
+	.DB	UARTDBASE+8 + UART_LSR		; LINE STATUS PORT (LSR)
 	.DW	UARTCFG				; LINE CONFIGURATION
 	.DW	0				; SHOULD NEVER NEED INT HANDLER
-;
-	.ECHO	"UART: MODE=DUAL, IO="
-	.ECHO	UARTDBASE+0
-	.ECHO	"\n"
-;
 	; DUAL UART CHANNEL B
 	.DB	0				; DEVICE NUMBER (UPDATED DURING INIT)
 	.DB	0				; UART TYPE
-	.DB	UARTDBASE+8			; IO PORT BASE (RBR, THR)
-	.DB	UARTDBASE+8 + UART_LSR		; LINE STATUS PORT (LSR)
+	.DB	UARTDBASE			; IO PORT BASE (RBR, THR)
+	.DB	UARTDBASE + UART_LSR		; LINE STATUS PORT (LSR)
 	.DW	UARTCFG				; LINE CONFIGURATION
 	.DW	0				; SHOULD NEVER NEED INT HANDLER
 ;
 	.ECHO	"UART: MODE=DUAL, IO="
 	.ECHO	UARTDBASE+8
 	.ECHO	"\n"
+;
+	.ECHO	"UART: MODE=DUAL, IO="
+	.ECHO	UARTDBASE+0
+	.ECHO	"\n"
 ;
 #ENDIF
 ;