From 34d25cb906bdb738eb8f131d77e79fc762a0d68a Mon Sep 17 00:00:00 2001
From: b1ackmai1er <difficultylevelhigh@gmail.com>
Date: Sun, 24 Mar 2024 12:19:58 +0800
Subject: [PATCH 1/3] Recovery button support for Duo

---
 Source/HBIOS/hbios.asm | 17 ++++++++++++++++-
 Source/HBIOS/std.asm   |  4 +++-
 Source/HBIOS/uart.asm  |  8 +++-----
 3 files changed, 22 insertions(+), 7 deletions(-)

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..f0126ead 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)
 ;

From 842a79ae5d910f0192bfd1524310039b62769698 Mon Sep 17 00:00:00 2001
From: b1ackmai1er <difficultylevelhigh@gmail.com>
Date: Sun, 24 Mar 2024 15:36:32 +0800
Subject: [PATCH 2/3] Correct the logical sequence of the Duo Dual UART ports

Make the first UART port detected be Channel A $78-$7F : CHSEL=1. ( logic 0 on the CHSEL selects the UART channel B while a logic 1 selects UART channel A. )
---
 Source/HBIOS/uart.asm | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/Source/HBIOS/uart.asm b/Source/HBIOS/uart.asm
index f0126ead..c33341d8 100644
--- a/Source/HBIOS/uart.asm
+++ b/Source/HBIOS/uart.asm
@@ -1163,6 +1163,13 @@ UART_CFG_MFP:
 	; DUAL UART CHANNEL A
 	.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)
+	.DW	UARTCFG				; LINE CONFIGURATION
+	.DW	0				; SHOULD NEVER NEED INT HANDLER
+	; DUAL UART CHANNEL B
+	.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)
 	.DW	UARTCFG				; LINE CONFIGURATION
@@ -1171,14 +1178,6 @@ UART_CFG_MFP:
 	.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)
-	.DW	UARTCFG				; LINE CONFIGURATION
-	.DW	0				; SHOULD NEVER NEED INT HANDLER
 ;
 	.ECHO	"UART: MODE=DUAL, IO="
 	.ECHO	UARTDBASE+8

From 7fe03123598a675462d831c1464c7f96f45e5c3e Mon Sep 17 00:00:00 2001
From: b1ackmai1er <difficultylevelhigh@gmail.com>
Date: Sun, 24 Mar 2024 17:53:42 +0800
Subject: [PATCH 3/3] Align assembly outout with data structure

---
 Source/HBIOS/uart.asm | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Source/HBIOS/uart.asm b/Source/HBIOS/uart.asm
index c33341d8..cd8fe8fb 100644
--- a/Source/HBIOS/uart.asm
+++ b/Source/HBIOS/uart.asm
@@ -1176,11 +1176,11 @@ UART_CFG_MFP:
 	.DW	0				; SHOULD NEVER NEED INT HANDLER
 ;
 	.ECHO	"UART: MODE=DUAL, IO="
-	.ECHO	UARTDBASE+0
+	.ECHO	UARTDBASE+8
 	.ECHO	"\n"
 ;
 	.ECHO	"UART: MODE=DUAL, IO="
-	.ECHO	UARTDBASE+8
+	.ECHO	UARTDBASE+0
 	.ECHO	"\n"
 ;
 #ENDIF