diff --git a/Doc/RomWBW Applications.pdf b/Doc/RomWBW Applications.pdf
index a225010b..8ab31688 100644
Binary files a/Doc/RomWBW Applications.pdf and b/Doc/RomWBW Applications.pdf differ
diff --git a/Doc/RomWBW Disk Catalog.pdf b/Doc/RomWBW Disk Catalog.pdf
index 60c65b0b..79b6d053 100644
Binary files a/Doc/RomWBW Disk Catalog.pdf and b/Doc/RomWBW Disk Catalog.pdf differ
diff --git a/Doc/RomWBW Hardware.pdf b/Doc/RomWBW Hardware.pdf
index 00d4940f..677e1b42 100644
Binary files a/Doc/RomWBW Hardware.pdf and b/Doc/RomWBW Hardware.pdf differ
diff --git a/Doc/RomWBW Introduction.pdf b/Doc/RomWBW Introduction.pdf
index 43e429cb..86988212 100644
Binary files a/Doc/RomWBW Introduction.pdf and b/Doc/RomWBW Introduction.pdf differ
diff --git a/Doc/RomWBW System Guide.pdf b/Doc/RomWBW System Guide.pdf
index a56c19ff..b596f10e 100644
Binary files a/Doc/RomWBW System Guide.pdf and b/Doc/RomWBW System Guide.pdf differ
diff --git a/Doc/RomWBW User Guide.pdf b/Doc/RomWBW User Guide.pdf
index 8da07e31..c96b2056 100644
Binary files a/Doc/RomWBW User Guide.pdf and b/Doc/RomWBW User Guide.pdf differ
diff --git a/ReadMe.md b/ReadMe.md
index 8370ef81..dcef157f 100644
--- a/ReadMe.md
+++ b/ReadMe.md
@@ -7,7 +7,7 @@
 **RomWBW Introduction** \
 Version 3.6 \
 Wayne Warthen  ([wwarthen@gmail.com](mailto:wwarthen@gmail.com)) \
-09 Dec 2025
+10 Dec 2025
 
 # Overview
 
@@ -363,6 +363,9 @@ let me know if I missed you!
 
 - Henk Berends added support for the MSX platform.
 
+- Jay Cotton provided the SCSI transport code upon which the SCSI driver
+  is based.
+
 ## Related Projects
 
 Outside of the hardware platforms adapted to RomWBW, there are a variety
diff --git a/ReadMe.txt b/ReadMe.txt
index 5d155098..99af8c31 100644
--- a/ReadMe.txt
+++ b/ReadMe.txt
@@ -1,6 +1,6 @@
 RomWBW Introduction
 Wayne Warthen (wwarthen@gmail.com)
-09 Dec 2025
+10 Dec 2025
 
 
 
@@ -370,6 +370,9 @@ let me know if I missed you!
 
 - Henk Berends added support for the MSX platform.
 
+- Jay Cotton provided the SCSI transport code upon which the SCSI driver
+  is based.
+
 
 Related Projects
 
diff --git a/Source/Apps/assign/assign.asm b/Source/Apps/assign/assign.asm
index b16d8d84..634ccd92 100644
--- a/Source/Apps/assign/assign.asm
+++ b/Source/Apps/assign/assign.asm
@@ -40,6 +40,7 @@
 ;                    overflow when the drives are finally added
 ;   2025-07-19 [D?N] Support for native USB drivers
 ;   2025-08-09 [WBW] Support for ESPSD driver
+;   2025-11-10 [WBW] Support for SCSI driver
 ;_______________________________________________________________________________
 ;
 ; ToDo:
@@ -2430,7 +2431,7 @@ devtbl:				; device table
 	.dw	dev04, dev05, dev06, dev07
 	.dw	dev08, dev09, dev10, dev11
 	.dw	dev12, dev13, dev14, dev15
-	.dw	dev16, dev17
+	.dw	dev16, dev17, dev18
 ;
 devunk	.db	"?",0
 dev00	.db	"MD",0
@@ -2450,9 +2451,10 @@ dev13	.db	"CHUSB",0
 dev14	.db	"CHSD",0
 dev15	.db	"USB",0
 dev16	.db	"ESPSD",0
-dev17	.equ	devunk
+dev17	.db	"SCSI",0
+dev18	.equ	devunk
 ;
-devcnt	.equ	18		; 18 device types defined
+devcnt	.equ	19		; 19 device types defined
 ;
 udevram		.db	"RAM",0
 udevrom		.db	"ROM",0
@@ -2470,10 +2472,10 @@ stack	.equ	$		; stack top
 ; Messages
 ;
 indent	.db	"   ",0
-msgban1	.db	"ASSIGN v2.2 for RomWBW CP/M ",0
+msgban1	.db	"ASSIGN v2.3 for RomWBW CP/M ",0
 msg22	.db	"2.2",0
 msg3	.db	"3",0
-msbban2	.db	", 9-Aug-2025",0
+msbban2	.db	",10-Dec-2025",0
 msghb	.db	" (HBIOS Mode)",0
 msgub	.db	" (UBIOS Mode)",0
 msgban3	.db	"Copyright 2025, Wayne Warthen, GNU GPL v3",0
diff --git a/Source/CBIOS/cbios.asm b/Source/CBIOS/cbios.asm
index 9f30a48a..ac3b6b13 100644
--- a/Source/CBIOS/cbios.asm
+++ b/Source/CBIOS/cbios.asm
@@ -3408,7 +3408,7 @@ DEVTBL:	; DEVICE TABLE
 	.DW	DEV04, DEV05, DEV06, DEV07
 	.DW	DEV08, DEV09, DEV10, DEV11
 	.DW	DEV12, DEV13, DEV14, DEV15
-	.DW	DEV16, DEV17
+	.DW	DEV16, DEV17, DEV18
 ;
 DEVUNK	.DB	"???$"
 DEV00	.DB	"MD$"
@@ -3428,7 +3428,8 @@ DEV13	.DB	"CHUSB$"
 DEV14	.DB	"CHSD$"
 DEV15	.DB	"USB$"
 DEV16	.DB	"ESPSD$"
-DEV17	.EQU	DEVUNK
+DEV17	.DB	"SCSI$"
+DEV18	.EQU	DEVUNK
 ;
 #ENDIF
 ;
diff --git a/Source/Doc/Hardware.md b/Source/Doc/Hardware.md
index 350d933d..dea1c43e 100644
--- a/Source/Doc/Hardware.md
+++ b/Source/Doc/Hardware.md
@@ -2478,6 +2478,7 @@ the active platform and configuration.
 | SD        | SD Card Interface                                      |
 | SYQ       | Iomega SparQ Drive on PPI                              |
 | ESPSD     | S100 ESP32-based SD Card Interface                     |
+| SCSI      | 5380 SCSI Interface                                    |
 
 ## Video
 
diff --git a/Source/Doc/Introduction.md b/Source/Doc/Introduction.md
index 34af573a..0ad7e5a3 100644
--- a/Source/Doc/Introduction.md
+++ b/Source/Doc/Introduction.md
@@ -347,6 +347,9 @@ please let me know if I missed you!
 
 * Henk Berends added support for the MSX platform.
 
+* Jay Cotton provided the SCSI transport code upon which the SCSI
+  driver is based.
+
 `\clearpage`{=latex}
 
 ## Related Projects
diff --git a/Source/Doc/SystemGuide.md b/Source/Doc/SystemGuide.md
index 3452b338..fa558b6d 100644
--- a/Source/Doc/SystemGuide.md
+++ b/Source/Doc/SystemGuide.md
@@ -1101,6 +1101,7 @@ below enumerates their values.
 | DIODEV_CHSD     | 0x0E   | CH375/376 SD Card                        | ch.asm     |
 | DIODEV_USB      | 0x0F   | CH376 Native USB Device                  | ch376.asm  |
 | DIODEV_ESPSD    | 0x10   | S100 ESP32 SD Card                       | espsd.asm  |
+| DIODEV_SCSI     | 0x11   | 5380 SCSI Interface                      | scsi.asm   |
 
 A fixed set of media types are defined. The currently defined media 
 types identifiers are listed below. Each driver will support one or
diff --git a/Source/HBIOS/Config/SZ180_std.asm b/Source/HBIOS/Config/SZ180_std.asm
index 57c31064..228f6665 100644
--- a/Source/HBIOS/Config/SZ180_std.asm
+++ b/Source/HBIOS/Config/SZ180_std.asm
@@ -82,3 +82,5 @@ SDCNT		.SET	1		; SD: NUMBER OF SD CARD DEVICES (1-2), FOR DSD/SC/MT ONLY
 ESPSDENABLE	.SET	TRUE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ESPSDCNT	.SET	1		; ESPSD: NUMBER OF BOARDS TO DETECT (1-2), 1-2 DEVICES PER BOARD
 ESPSD0DUAL	.SET	TRUE		; ESPSD 0: DUAL INTERFACE BOARD (DUAL SD)
+;
+SCSIENABLE	.SET	TRUE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
diff --git a/Source/HBIOS/Config/SZ80_std.asm b/Source/HBIOS/Config/SZ80_std.asm
index c7e6a62f..8146ad70 100644
--- a/Source/HBIOS/Config/SZ80_std.asm
+++ b/Source/HBIOS/Config/SZ80_std.asm
@@ -72,3 +72,5 @@ PPIDEENABLE	.SET	TRUE		; PPIDE: ENABLE PARALLEL PORT IDE DISK DRIVER (PPIDE.ASM)
 ESPSDENABLE	.SET	TRUE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ESPSDCNT	.SET	1		; ESPSD: NUMBER OF BOARDS TO DETECT (1-2), 1-2 DEVICES PER BOARD
 ESPSD0DUAL	.SET	TRUE		; ESPSD 0: DUAL INTERFACE BOARD (DUAL SD)
+;
+SCSIENABLE	.SET	TRUE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
diff --git a/Source/HBIOS/Config/SZ80_t35.asm b/Source/HBIOS/Config/SZ80_t35.asm
index fffe50e4..157f6c12 100644
--- a/Source/HBIOS/Config/SZ80_t35.asm
+++ b/Source/HBIOS/Config/SZ80_t35.asm
@@ -83,3 +83,5 @@ SDENABLE	.SET	TRUE		; SD: ENABLE SD CARD DISK DRIVER (SD.ASM)
 ESPSDENABLE	.SET	TRUE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ESPSDCNT	.SET	1		; ESPSD: NUMBER OF BOARDS TO DETECT (1-2), 1-2 DEVICES PER BOARD
 ESPSD0DUAL	.SET	TRUE		; ESPSD 0: DUAL INTERFACE BOARD (DUAL SD)
+;
+SCSIENABLE	.SET	TRUE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
diff --git a/Source/HBIOS/cfg_DUO.asm b/Source/HBIOS/cfg_DUO.asm
index 8312eaeb..b70ad13e 100644
--- a/Source/HBIOS/cfg_DUO.asm
+++ b/Source/HBIOS/cfg_DUO.asm
@@ -375,6 +375,8 @@ SYQ1BASE	.SET	LPT1BASE	; SYQ 1: BASE I/O ADDRESS OF PPI FOR SYQ
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO4BASE	.SET	$90		; PIO: PIO REGISTERS BASE ADR FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
diff --git a/Source/HBIOS/cfg_DYNO.asm b/Source/HBIOS/cfg_DYNO.asm
index 5fa40dc9..ad726905 100644
--- a/Source/HBIOS/cfg_DYNO.asm
+++ b/Source/HBIOS/cfg_DYNO.asm
@@ -359,6 +359,8 @@ SYQENABLE	.SET	FALSE		; SYQ: ENABLE SYQUEST SPARQ DISK DRIVER (SYQ.ASM)
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_EPITX.asm b/Source/HBIOS/cfg_EPITX.asm
index 311d7423..2d01e721 100644
--- a/Source/HBIOS/cfg_EPITX.asm
+++ b/Source/HBIOS/cfg_EPITX.asm
@@ -385,6 +385,8 @@ SYQ1BASE	.SET	LPT1BASE	; SYQ 1: BASE I/O ADDRESS OF PPI FOR SYQ
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_EZZ80.asm b/Source/HBIOS/cfg_EZZ80.asm
index 78c91ac7..69f0ef11 100644
--- a/Source/HBIOS/cfg_EZZ80.asm
+++ b/Source/HBIOS/cfg_EZZ80.asm
@@ -394,6 +394,8 @@ SYQ1BASE	.SET	LPT1BASE	; SYQ 1: BASE I/O ADDRESS OF PPI FOR SYQ
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_GMZ180.asm b/Source/HBIOS/cfg_GMZ180.asm
index b5565571..3c403293 100644
--- a/Source/HBIOS/cfg_GMZ180.asm
+++ b/Source/HBIOS/cfg_GMZ180.asm
@@ -384,6 +384,8 @@ SYQ1BASE	.SET	LPT1BASE	; SYQ 1: BASE I/O ADDRESS OF PPI FOR SYQ
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_HEATH.asm b/Source/HBIOS/cfg_HEATH.asm
index 79dd9373..87c1f40a 100644
--- a/Source/HBIOS/cfg_HEATH.asm
+++ b/Source/HBIOS/cfg_HEATH.asm
@@ -384,6 +384,8 @@ SYQ1BASE	.SET	LPT1BASE	; SYQ 1: BASE I/O ADDRESS OF PPI FOR SYQ
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_MASTER.asm b/Source/HBIOS/cfg_MASTER.asm
index c30cdf2e..29006f8d 100644
--- a/Source/HBIOS/cfg_MASTER.asm
+++ b/Source/HBIOS/cfg_MASTER.asm
@@ -495,6 +495,13 @@ ESPSD0DUAL	.EQU	TRUE		; ESPSD 0: DUAL INTERFACE BOARD (DUAL SD)
 ESPSD1BASE	.EQU	$82		; ESPSD 1: ESP32 INTERFACE IO BASE ADR
 ESPSD1DUAL	.EQU	TRUE		; ESPSD 1: DUAL INTERFACE BOARD (DUAL SD)
 ;
+SCSIENABLE	.EQU	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+SCSITRACE	.EQU	1		; SCSI: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
+SCSICNT		.EQU	2		; SCSI: NUMBER OF TARGET DEVICES (1-2)
+SCSI_TID	.EQU	0		; SCSI: TARGET DEVICE ID (0-6)
+SCSI0_LUN	.EQU	0		; SCSI0: TARGET LUN
+SCSI1_LUN	.EQU	1		; SCSI1: TARGET LUN
+;
 PIO_4P		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO4BASE	.EQU	$90		; PIO: PIO REGISTERS BASE ADR FOR ECB 4P BOARD
 PIO_ZP		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
diff --git a/Source/HBIOS/cfg_MBC.asm b/Source/HBIOS/cfg_MBC.asm
index 7d3dfedb..928c83ad 100644
--- a/Source/HBIOS/cfg_MBC.asm
+++ b/Source/HBIOS/cfg_MBC.asm
@@ -363,6 +363,8 @@ SYQ1BASE	.SET	LPT1BASE	; SYQ 1: BASE I/O ADDRESS OF PPI FOR SYQ
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO4BASE	.SET	$90		; PIO: PIO REGISTERS BASE ADR FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
diff --git a/Source/HBIOS/cfg_MK4.asm b/Source/HBIOS/cfg_MK4.asm
index ce9b0170..75ea1cc3 100644
--- a/Source/HBIOS/cfg_MK4.asm
+++ b/Source/HBIOS/cfg_MK4.asm
@@ -356,6 +356,8 @@ SYQENABLE	.SET	FALSE		; SYQ: ENABLE SYQUEST SPARQ DISK DRIVER (SYQ.ASM)
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO4BASE	.SET	$90		; PIO: PIO REGISTERS BASE ADR FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
diff --git a/Source/HBIOS/cfg_MON.asm b/Source/HBIOS/cfg_MON.asm
index 1dc2529b..478ad81c 100644
--- a/Source/HBIOS/cfg_MON.asm
+++ b/Source/HBIOS/cfg_MON.asm
@@ -391,6 +391,8 @@ SYQ1BASE	.SET	LPT1BASE	; SYQ 1: BASE I/O ADDRESS OF PPI FOR SYQ
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_MSX.asm b/Source/HBIOS/cfg_MSX.asm
index fee0e2c8..386c5371 100644
--- a/Source/HBIOS/cfg_MSX.asm
+++ b/Source/HBIOS/cfg_MSX.asm
@@ -398,6 +398,8 @@ SYQ1BASE	.SET	LPT1BASE	; SYQ 1: BASE I/O ADDRESS OF PPI FOR SYQ
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_N8.asm b/Source/HBIOS/cfg_N8.asm
index 56a491f1..be168432 100644
--- a/Source/HBIOS/cfg_N8.asm
+++ b/Source/HBIOS/cfg_N8.asm
@@ -358,6 +358,8 @@ SYQENABLE	.SET	FALSE		; SYQ: ENABLE SYQUEST SPARQ DISK DRIVER (SYQ.ASM)
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO4BASE	.SET	$90		; PIO: PIO REGISTERS BASE ADR FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
diff --git a/Source/HBIOS/cfg_N8PC.asm b/Source/HBIOS/cfg_N8PC.asm
index ebd5ce58..706ea7e6 100644
--- a/Source/HBIOS/cfg_N8PC.asm
+++ b/Source/HBIOS/cfg_N8PC.asm
@@ -357,6 +357,8 @@ SYQENABLE	.SET	FALSE		; SYQ: ENABLE SYQUEST SPARQ DISK DRIVER (SYQ.ASM)
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO4BASE	.SET	$90		; PIO: PIO REGISTERS BASE ADR FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
diff --git a/Source/HBIOS/cfg_NABU.asm b/Source/HBIOS/cfg_NABU.asm
index 32c74928..56f78117 100644
--- a/Source/HBIOS/cfg_NABU.asm
+++ b/Source/HBIOS/cfg_NABU.asm
@@ -394,6 +394,8 @@ SYQ1BASE	.SET	LPT1BASE	; SYQ 1: BASE I/O ADDRESS OF PPI FOR SYQ
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_RCEZ80.asm b/Source/HBIOS/cfg_RCEZ80.asm
index d1f8561d..f39f34e6 100644
--- a/Source/HBIOS/cfg_RCEZ80.asm
+++ b/Source/HBIOS/cfg_RCEZ80.asm
@@ -395,6 +395,8 @@ SYQ1BASE	.SET	LPT1BASE	; SYQ 1: BASE I/O ADDRESS OF PPI FOR SYQ
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_RCZ180.asm b/Source/HBIOS/cfg_RCZ180.asm
index 63cd948a..0676bfe1 100644
--- a/Source/HBIOS/cfg_RCZ180.asm
+++ b/Source/HBIOS/cfg_RCZ180.asm
@@ -392,6 +392,8 @@ SYQ1BASE	.SET	LPT1BASE	; SYQ 1: BASE I/O ADDRESS OF PPI FOR SYQ
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_RCZ280.asm b/Source/HBIOS/cfg_RCZ280.asm
index 2a3ca400..d1aea887 100644
--- a/Source/HBIOS/cfg_RCZ280.asm
+++ b/Source/HBIOS/cfg_RCZ280.asm
@@ -402,6 +402,8 @@ SYQ1BASE	.SET	LPT1BASE	; SYQ 1: BASE I/O ADDRESS OF PPI FOR SYQ
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_RCZ80.asm b/Source/HBIOS/cfg_RCZ80.asm
index 873b47d0..b391e3e3 100644
--- a/Source/HBIOS/cfg_RCZ80.asm
+++ b/Source/HBIOS/cfg_RCZ80.asm
@@ -397,6 +397,8 @@ SYQ1BASE	.SET	LPT1BASE	; SYQ 1: BASE I/O ADDRESS OF PPI FOR SYQ
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_RPH.asm b/Source/HBIOS/cfg_RPH.asm
index a742b4e4..97677765 100644
--- a/Source/HBIOS/cfg_RPH.asm
+++ b/Source/HBIOS/cfg_RPH.asm
@@ -339,6 +339,8 @@ SYQENABLE	.SET	FALSE		; SYQ: ENABLE SYQUEST SPARQ DISK DRIVER (SYQ.ASM)
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO4BASE	.SET	$90		; PIO: PIO REGISTERS BASE ADR FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
diff --git a/Source/HBIOS/cfg_SBC.asm b/Source/HBIOS/cfg_SBC.asm
index 67da3e92..f7a2dffa 100644
--- a/Source/HBIOS/cfg_SBC.asm
+++ b/Source/HBIOS/cfg_SBC.asm
@@ -347,6 +347,8 @@ SYQENABLE	.SET	FALSE		; SYQ: ENABLE SYQUEST SPARQ DISK DRIVER (SYQ.ASM)
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO4BASE	.SET	$90		; PIO: PIO REGISTERS BASE ADR FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
diff --git a/Source/HBIOS/cfg_SCZ180.asm b/Source/HBIOS/cfg_SCZ180.asm
index 4ced8c68..baefc092 100644
--- a/Source/HBIOS/cfg_SCZ180.asm
+++ b/Source/HBIOS/cfg_SCZ180.asm
@@ -389,6 +389,8 @@ SYQ1BASE	.SET	LPT1BASE	; SYQ 1: BASE I/O ADDRESS OF PPI FOR SYQ
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_SZ180.asm b/Source/HBIOS/cfg_SZ180.asm
index bd233093..574d07e5 100644
--- a/Source/HBIOS/cfg_SZ180.asm
+++ b/Source/HBIOS/cfg_SZ180.asm
@@ -381,6 +381,13 @@ ESPSD0DUAL	.SET	TRUE		; ESPSD 0: DUAL INTERFACE BOARD (DUAL SD)
 ESPSD1BASE	.SET	$82		; ESPSD 1: ESP32 INTERFACE IO BASE ADR
 ESPSD1DUAL	.SET	TRUE		; ESPSD 1: DUAL INTERFACE BOARD (DUAL SD)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+SCSITRACE	.SET	1		; SCSI: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
+SCSICNT		.SET	2		; SCSI: NUMBER OF TARGET DEVICES (1-2)
+SCSI_TID	.SET	0		; SCSI: TARGET DEVICE ID (0-6)
+SCSI0_LUN	.SET	0		; SCSI0: TARGET LUN
+SCSI1_LUN	.SET	1		; SCSI1: TARGET LUN
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_SZ80.asm b/Source/HBIOS/cfg_SZ80.asm
index 3b3b9026..6f7d994b 100644
--- a/Source/HBIOS/cfg_SZ80.asm
+++ b/Source/HBIOS/cfg_SZ80.asm
@@ -370,6 +370,13 @@ ESPSD0DUAL	.SET	TRUE		; ESPSD 0: DUAL INTERFACE BOARD (DUAL SD)
 ESPSD1BASE	.SET	$82		; ESPSD 1: ESP32 INTERFACE IO BASE ADR
 ESPSD1DUAL	.SET	TRUE		; ESPSD 1: DUAL INTERFACE BOARD (DUAL SD)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+SCSITRACE	.SET	1		; SCSI: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
+SCSICNT		.SET	2		; SCSI: NUMBER OF TARGET DEVICES (1-2)
+SCSI_TID	.SET	0		; SCSI: TARGET DEVICE ID (0-6)
+SCSI0_LUN	.SET	0		; SCSI0: TARGET LUN
+SCSI1_LUN	.SET	1		; SCSI1: TARGET LUN
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_Z80RETRO.asm b/Source/HBIOS/cfg_Z80RETRO.asm
index 0de1dc3c..70271cb6 100644
--- a/Source/HBIOS/cfg_Z80RETRO.asm
+++ b/Source/HBIOS/cfg_Z80RETRO.asm
@@ -314,6 +314,8 @@ SYQENABLE	.SET	FALSE		; SYQ: ENABLE SYQUEST SPARQ DISK DRIVER (SYQ.ASM)
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_ZETA.asm b/Source/HBIOS/cfg_ZETA.asm
index 8c38ad10..2c666b2a 100644
--- a/Source/HBIOS/cfg_ZETA.asm
+++ b/Source/HBIOS/cfg_ZETA.asm
@@ -284,6 +284,8 @@ SYQENABLE	.SET	FALSE		; SYQ: ENABLE SYQUEST SPARQ DISK DRIVER (SYQ.ASM)
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/cfg_ZETA2.asm b/Source/HBIOS/cfg_ZETA2.asm
index 7b35ac02..3bc56c5f 100644
--- a/Source/HBIOS/cfg_ZETA2.asm
+++ b/Source/HBIOS/cfg_ZETA2.asm
@@ -295,6 +295,8 @@ SYQENABLE	.SET	FALSE		; SYQ: ENABLE SYQUEST SPARQ DISK DRIVER (SYQ.ASM)
 ;
 ESPSDENABLE	.SET	FALSE		; ESPSD: ENABLE S100 ESP32 SD DISK DRIVER (ESPSD.ASM)
 ;
+SCSIENABLE	.SET	FALSE		; SCSI: ENABLE 3580-BASED SCSI INTERFACE (SCSI.ASM)
+;
 PIO_4P		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.SET	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
diff --git a/Source/HBIOS/hbios.asm b/Source/HBIOS/hbios.asm
index 3d81382d..4cec5430 100644
--- a/Source/HBIOS/hbios.asm
+++ b/Source/HBIOS/hbios.asm
@@ -4438,6 +4438,9 @@ HB_INITTBL:
 #IF (ESPSDENABLE)
 	.DW	ESPSD_INIT
 #ENDIF
+#IF (SCSIENABLE)
+	.DW	SCSI_INIT
+#ENDIF
 #IF (PRPENABLE)
 	.DW	PRP_INIT
 #ENDIF
@@ -9321,6 +9324,15 @@ SIZ_ESPSD	.EQU	$ - ORG_ESPSD
 		MEMECHO	" bytes.\n"
 #ENDIF
 ;
+#IF (SCSIENABLE)
+ORG_SCSI		.EQU	$
+  #INCLUDE "scsi.asm"
+SIZ_SCSI	.EQU	$ - ORG_SCSI
+		MEMECHO	"SCSI occupies "
+		MEMECHO	SIZ_SCSI
+		MEMECHO	" bytes.\n"
+#ENDIF
+;
 #IF (ESPENABLE)
 ORG_ESP		.EQU	$
   #INCLUDE "esp.asm"
diff --git a/Source/HBIOS/hbios.inc b/Source/HBIOS/hbios.inc
index eb4749d0..f642679f 100644
--- a/Source/HBIOS/hbios.inc
+++ b/Source/HBIOS/hbios.inc
@@ -427,6 +427,7 @@ DIODEV_CHUSB	.EQU	$0D
 DIODEV_CHSD	.EQU	$0E
 DIODEV_USB	.EQU	$0F
 DIODEV_ESPSD	.EQU	$10
+DIODEV_SCSI	.EQU	$11
 ;
 ; RTC DEVICE IDS
 ;
diff --git a/Source/HBIOS/invntdev.asm b/Source/HBIOS/invntdev.asm
index 1b86aab5..1d4e9484 100644
--- a/Source/HBIOS/invntdev.asm
+++ b/Source/HBIOS/invntdev.asm
@@ -1,6 +1,6 @@
 ;==============================================================================
 ; DEVIVE INVENTORY - Inventory Device
-; Version  August-2025
+; Version  December-2025
 ;==============================================================================
 ;
 ; This was extracted from HBIOS and converted into a ROM Application
@@ -11,6 +11,7 @@
 ; Change Log:
 ;   2025-06-30 [MAP] Initial Release copied from HBIOS.ASM
 ;   2025-08-09 [WBW] Add support for ESPSD driver
+;   2025-12-10 [WBW] Add support for SCSI driver
 ;______________________________________________________________________________
 ;
 ; Include Files
@@ -584,6 +585,7 @@ PS_DDCHUSB	.TEXT	"CHUSB$"
 PS_DDCHSD	.TEXT	"CHSD$"
 PS_DDCHNATUSB	.TEXT	"USB$"
 PS_DDESPSD	.TEXT	"ESPSD$"
+PS_DDSCSI	.TEXT	"SCSI$"
 ;
 ; DISK TYPE STRINGS
 ;
diff --git a/Source/HBIOS/scsi.asm b/Source/HBIOS/scsi.asm
new file mode 100644
index 00000000..e806a625
--- /dev/null
+++ b/Source/HBIOS/scsi.asm
@@ -0,0 +1,808 @@
+;
+;=============================================================================
+;   SCSI DISK DRIVER FOR 5380
+;=============================================================================
+;
+; DISK DEVICE DRIVER FOR THE 5380 SCSI CHIP.
+; DERIVED FROM CODE PROVIDED BY JAY COTTON.
+;
+; TODO:
+;  - IMPLEMENT INQUIRY COMMAND AND DISPLAY DATA AT INIT
+;  - IMPLEMENT CAPACITY COMMAND
+;  - DO SOMETHING IN INITDEV TO CONFIRM LUN EXISTS
+;
+; NOTES:
+;  - CAPACITY IS CURRENTLY HARD-CODED TO 200000 BLOCKS (1GB OF DATA)
+;
+SCSIBASE		.EQU	$40
+;
+; SCSI DEVICE STATUS CODES
+;
+SCSI_STOK		.EQU	0
+SCSI_STNOMEDIA		.EQU	-1
+SCSI_STIOERR		.EQU	-2
+SCSI_STTO		.EQU	-3
+SCSI_STNOTRDY		.EQU	-4
+;
+; NCR 5380 I/O REGISTERS
+;
+SCSI_SR_CSD	.EQU	SCSIBASE	; CURRENT SCSI DATA
+SCSI_SR_ICR	.EQU	SCSIBASE + $01	; INITIATOR COMMAND
+SCSI_SR_MR	.EQU	SCSIBASE + $02	; MODE
+SCSI_SR_TCR	.EQU	SCSIBASE + $03	; TARGET COMMAND
+SCSI_SR_CSBS	.EQU	SCSIBASE + $04	; CURRENT SCSI BUS STAT.
+SCSI_SR_BSR	.EQU	SCSIBASE + $05	; BUS STATUS
+SCSI_SR_IDR	.EQU	SCSIBASE + $06	; INITIATOR DMA RECV.
+SCSI_SR_RPI	.EQU	SCSIBASE + $07	; RESET PARITY/IRQ
+;
+; NCR 5380 OUTPUT ONLY REGISTERS
+;
+SCSI_SR_ODR	.EQU	SCSIBASE	; OUTPUT DATA
+SCSI_SR_SER	.EQU	SCSIBASE + $04	; SELECT ENABLE
+SCSI_SR_SDS	.EQU	SCSIBASE + $05	; START DMA SEND
+SCSI_SR_SDTR	.EQU	SCSIBASE + $06	; START TARGET DMA RECV.
+SCSI_SR_SDIR	.EQU	SCSIBASE + $07	; START INITIATOR DMA RECV.
+;
+; SCSI CURRENT BUS STATUS BIT MASKS
+;
+SCSI_SM_RST	.EQU	$80		; RESET
+SCSI_SM_BSY	.EQU	$40		; BUSY
+SCSI_SM_REQ	.EQU	$20		; REQUEST
+SCSI_SM_MSG	.EQU	$10		; MESSAGE
+SCSI_SM_CD	.EQU	$08		; CMD/DATA
+SCSI_SM_IO	.EQU	$04		; IN/OUT
+SCSI_SM_SEL	.EQU	$02		; SELECT
+SCSI_SM_DBP	.EQU	$01		; PARITY BIT
+;
+SCSI_SM_PHM	.EQU	$08		; PHASE MATCH BIT
+;
+; SDCI DEVICE CONFIGURATION
+;
+; PER DEVICE DATA OFFSETS IN CFG BLOCK
+;
+SCSI_DEV	.EQU	0		; OFFSET OF DEVICE NUMBER (BYTE)
+SCSI_IOBASE	.EQU	1		; IO BASE ADDRESS (BYTE)
+SCSI_LUN	.EQU	2		; TARGET LUN
+SCSI_STAT	.EQU	3		; LAST STATUS (BYTE)
+SCSI_MEDCAP	.EQU	4		; MEDIA CAPACITY (DWORD)
+SCSI_LBA	.EQU	8		; OFFSET OF LBA (DWORD)
+;                                       
+SCSI_CFGSIZ	.EQU	12		; SIZE OF CFG TBL ENTRIES
+;
+SCSI_CFGTBL:
+;
+#IF (SCSICNT >= 1)
+;
+SCSI0_CFG:
+	.DB	$FE			; DRIVER DEVICE NUMBER (FILLED DYNAMICALLY)
+	.DB	SCSIBASE		; IO BASE ADDRESS
+	.DB	SCSI0_LUN		; SCSI TARGET LUN
+	.DB	SCSI_STNOTRDY		; DEVICE STATUS
+	.DW	$0000,$0020		; DEVICE CAPACITY (BLOCKS)
+	.DW	0,0			; CURRENT LBA
+;
+	DEVECHO	"SCSI: IO="
+	DEVECHO	SCSIBASE
+	DEVECHO ", LUN="
+	DEVECHO SCSI0_LUN
+	DEVECHO	"\n"
+#ENDIF
+;
+#IF (SCSICNT >= 2)
+	.DB	$FE			; DRIVER DEVICE NUMBER (FILLED DYNAMICALLY)
+	.DB	SCSIBASE		; IO BASE ADDRESS
+	.DB	SCSI1_LUN		; SCSI TARGET LUN
+	.DB	SCSI_STNOTRDY		; DEVICE STATUS
+	.DW	$0000,$0020		; DEVICE CAPACITY (BLOCKS)
+	.DW	0,0			; CURRENT LBA
+;
+	DEVECHO	"SCSI: IO="
+	DEVECHO	SCSIBASE
+	DEVECHO ", LUN="
+	DEVECHO SCSI1_LUN
+	DEVECHO	"\n"
+#ENDIF
+;
+#IF ($ - SCSI_CFGTBL) != (SCSICNT * 2 * SCSI_CFGSIZ)
+	.ECHO	"*** INVALID SCSI CONFIG TABLE ***\n"
+#ENDIF
+;
+	.DB	$FF			; END OF TABLE MARKER
+;
+;=============================================================================
+; INITIALIZATION ENTRY POINT
+;=============================================================================
+;
+SCSI_INIT:
+	CALL	NEWLINE			; FORMATTING
+	PRTS("SCSI:$")			; TAG
+;
+	PRTS(" IO=0x$")			; LABEL FOR IO ADDRESS
+	LD	A,SCSIBASE		; GET IO BASE ADDRES
+	CALL	PRTHEXBYTE		; DISPLAY IT
+;
+	CALL	SCSI_DETECT		; DETECT THE SCSI INTERFACE
+	JR	Z,SCSI_INIT1		; IF FOUND CONTINUE
+	PRTS(" NOT PRESENT$")		; SHOW NOT PRESENT
+	XOR	A			; SUCCESS
+	RET				; AND BAIL OUT
+;
+SCSI_INIT1:
+	XOR	A			; ZERO ACCUM
+	LD	(SCSI_DEVNUM),A		; INIT DEV UNIT NUM FOR DYNAMIC ASSIGNMENT
+	LD	IY,SCSI_CFGTBL		; POINT TO START OF CONFIG TABLE
+;
+SCSI_INIT2:
+	LD	A,(IY)			; LOAD FIRST BYTE TO CHECK FOR END
+	CP	$FF			; CHECK FOR END OF TABLE VALUE
+	RET	Z			; RETURN IF DONE
+;
+	CALL	SCSI_INIT3		; REGISTER & INIT DEVICE
+;
+	LD	DE,SCSI_CFGSIZ		; SIZE OF CFG TABLE ENTRY
+	ADD	IY,DE			; BUMP POINTER
+	JP	SCSI_INIT2		; AND LOOP
+;
+SCSI_INIT3:
+	; UPDATE DRIVER RELATIVE UNIT NUMBER IN CONFIG TABLE
+	LD	A,(SCSI_DEVNUM)		; GET NEXT UNIT NUM TO ASSIGN
+	LD	(IY+SCSI_DEV),A		; UPDATE IT
+	INC	A			; BUMP TO NEXT UNIT NUM TO ASSIGN
+	LD	(SCSI_DEVNUM),A		; SAVE IT
+;
+	; ADD UNIT TO GLOBAL DISK UNIT TABLE
+	LD	BC,SCSI_FNTBL		; BC := FUNC TABLE ADR
+	PUSH	IY			; CFG ENTRY POINTER
+	POP	DE			; COPY TO DE
+	CALL	DIO_ADDENT		; ADD ENTRY TO GLOBAL DISK DEV TABLE
+;
+	CALL	SCSI_PRTPREFIX		; TAG FOR ACTIVE DEVICE
+;
+	PRTS(" LUN=$")			; LUN LABEL
+	LD	A,(IY+SCSI_LUN)		; LOAD LUN
+	CALL	PRTDEC8			; DISPLAY IT
+;
+	CALL	SCSI_INITDEV		; INITIALIZE DEVICE
+#IF (SCSITRACE < 2)
+	JP	NZ,SCSI_PRTSTAT
+#ENDIF
+	RET	NZ
+;
+	; PRINT STORAGE CAPACITY (BLOCK COUNT)
+	PRTS(" BLOCKS=0x$")		; PRINT FIELD LABEL
+	LD	A,SCSI_MEDCAP		; OFFSET TO CAPACITY FIELD
+	CALL	LDHLIYA			; HL := IY + A, REG A TRASHED
+	CALL	LD32			; GET THE CAPACITY VALUE
+	CALL	PRTHEX32		; PRINT HEX VALUE
+;
+	; PRINT STORAGE SIZE IN MB
+	PRTS(" SIZE=$")			; PRINT FIELD LABEL
+	LD	B,11			; 11 BIT SHIFT TO CONVERT BLOCKS --> MB
+	CALL	SRL32			; RIGHT SHIFT
+	CALL	PRTDEC32		; PRINT DWORD IN DECIMAL
+	PRTS("MB$")			; PRINT SUFFIX
+;
+	XOR	A			; SUCCESS
+	RET
+;
+;=============================================================================
+; DRIVER FUNCTION TABLE
+;=============================================================================
+;
+SCSI_FNTBL:
+	.DW	SCSI_STATUS
+	.DW	SCSI_RESET
+	.DW	SCSI_SEEK
+	.DW	SCSI_READ
+	.DW	SCSI_WRITE
+	.DW	SCSI_VERIFY
+	.DW	SCSI_FORMAT
+	.DW	SCSI_DEVICE
+	.DW	SCSI_MEDIA
+	.DW	SCSI_DEFMED
+	.DW	SCSI_CAP
+	.DW	SCSI_GEOM
+#IF (($ - SCSI_FNTBL) != (DIO_FNCNT * 2))
+	.ECHO	"*** INVALID SCSI FUNCTION TABLE ***\n"
+#ENDIF
+;
+SCSI_VERIFY:
+SCSI_FORMAT:
+SCSI_DEFMED:
+	SYSCHKERR(ERR_NOTIMPL)		; NOT IMPLEMENTED
+	RET
+;
+;
+;
+SCSI_READ:
+	CALL	HB_DSKREAD		; HOOK HBIOS DISK READ SUPERVISOR
+	LD	A,$08			; SETUP READ COMMAND
+	JR	SCSI_IO			; DO THE IO
+;
+;
+;
+SCSI_WRITE:
+	CALL	HB_DSKWRITE		; HOOK HBIOS DISK WRITE SUPERVISOR
+	LD	A,$0A			; SETUP WRITE COMMAND
+	JR	SCSI_IO			; DO THE IO
+;
+;
+;
+SCSI_IO:
+	LD	(SCSI_DSKBUF),HL	; SAVE DISK BUFFER ADDRESS
+	; SETUP SCSI COMMAND
+	LD	(SCSI_S_CDB),A		; SET SCSI COMMAND
+	; SETUP DISK BUFFER POINTERS
+	LD	(SCSI_BUF_OUT),HL	; INPUT BUFFER
+	LD	(SCSI_BUF_IN),HL	; OUTPUT BUFFER
+	; SETUP LUN/LBA
+	LD	A,(IY+SCSI_LUN)		; PUT LUN IN ACCUM
+	RRCA				; MOVE TO TOP 3 BITS
+	RRCA				; ...
+	RRCA				; ...
+	OR	(IY+SCSI_LBA+2)		; MERGE WITH TOP OF LBA
+	LD	(SCSI_CUR_LUN),A	; PUT IN CDB
+	LD	A,(IY+SCSI_LBA+1)	; LBA MID
+	LD	(SCSI_CUR_LBN),A	; PUT IN CDB
+	LD	A,(IY+SCSI_LBA+0)	; LBA MID
+	LD	(SCSI_CUR_LBN+1),A	; PUT IN CDB
+	PUSH	IX			; SAVE IX
+	LD	IX,SCSI_S_IOT		; SET POINTER
+	CALL	SCSI_GO			; DO THE SCSI TRANSACTION
+	POP	IX			; RESTORE IX
+	JR	NZ,SCSI_IO1		; IF ERROR, SKIP INCREMENT
+	; INCREMENT LBA
+	LD	A,SCSI_LBA		; LBA OFFSET
+	CALL	LDHLIYA			; HL := IY + A, REG A TRASHED
+	CALL	INC32HL			; INCREMENT THE VALUE
+	; INCREMENT DMA
+	LD	HL,SCSI_DSKBUF+1	; POINT TO MSB OF BUFFER ADR
+	INC	(HL)			; BUMP DMA BY
+	INC	(HL)			; ... 512 BYTES
+	XOR	A			; SIGNAL SUCCESS
+SCSI_IO1:
+	LD	HL,(SCSI_DSKBUF)	; CURRENT DMA TO HL
+	OR	A			; SET FLAGS
+	RET	Z			; DONE IF NO ERROR
+	LD	A,ERR_IO		; SIGNAL IO ERROR
+	OR	A			; SET FLAGS
+	RET				; AND DONE
+;
+;
+;
+SCSI_STATUS:
+	LD	A,(IY+SCSI_STAT)	; GET STATUS OF SELECTED DEVICE
+	OR	A			; SET FLAGS
+	RET				; AND RETURN
+;
+;
+;
+SCSI_RESET:
+	CALL	SCSI_INITDEV		; REINITIALIZE UNIT
+	OR	A			; SET RESULT FLAGS
+	RET
+;
+;
+;
+SCSI_DEVICE:
+	LD	D,DIODEV_SCSI		; D := DEVICE TYPE
+	LD	E,(IY+SCSI_DEV)		; E := PHYSICAL DEVICE NUMBER
+	LD	C,%00110000		; C := GENERIC HARD DISK ATTRIBUTES
+	LD	H,0			; H := MODE
+	LD	L,(SCSI_IOBASE)		; L := BASE I/O ADDRESS
+	XOR	A			; SIGNAL SUCCESS
+	RET
+;
+;
+;
+SCSI_MEDIA:
+	LD	A,E			; GET FLAGS
+	OR	A			; SET FLAGS
+	JR	Z,SCSI_MEDIA1		; JUST REPORT CURRENT STATUS AND MEDIA
+	CALL	SCSI_INITDEV		; REINITIALIZE DEVICE
+;
+SCSI_MEDIA1:
+	LD	A,(IY+SCSI_STAT)	; GET STATUS
+	OR	A			; SET FLAGS
+	LD	D,0			; NO MEDIA CHANGE DETECTED
+	LD	E,MID_HD		; ASSUME WE ARE OK
+	RET	Z			; RETURN IF GOOD INIT
+	LD	E,MID_NONE		; SIGNAL NO MEDIA
+	LD	A,ERR_NOMEDIA		; NO MEDIA ERROR
+	OR	A			; SET FLAGS
+	RET				; AND RETURN
+;
+;
+;
+SCSI_SEEK:
+	BIT	7,D			; CHECK FOR LBA FLAG
+	CALL	Z,HB_CHS2LBA		; CLEAR MEANS CHS, CONVERT TO LBA
+	RES	7,D			; CLEAR FLAG REGARDLESS (DOES NO HARM IF ALREADY LBA)
+	LD	(IY+SCSI_LBA+0),L	; SAVE NEW LBA
+	LD	(IY+SCSI_LBA+1),H	; ...
+	LD	(IY+SCSI_LBA+2),E	; ...
+	LD	(IY+SCSI_LBA+3),D	; ...
+	XOR	A			; SIGNAL SUCCESS
+	RET				; AND RETURN
+;
+;
+;
+SCSI_CAP:
+	LD	A,(IY+SCSI_STAT)	; GET STATUS
+	PUSH	AF			; SAVE IT
+	LD	A,SCSI_MEDCAP		; OFFSET TO CAPACITY FIELD
+	CALL	LDHLIYA			; HL := IY + A, REG A TRASHED
+	CALL	LD32			; GET THE CURRENT CAPACITY INTO DE:HL
+	LD	BC,512			; 512 BYTES PER BLOCK
+	POP	AF			; RECOVER STATUS
+	OR	A			; SET FLAGS
+	RET
+;
+;
+;
+SCSI_GEOM:
+	; FOR LBA, WE SIMULATE CHS ACCESS USING 16 HEADS AND 16 SECTORS
+	; RETURN HS:CC -> DE:HL, SET HIGH BIT OF D TO INDICATE LBA CAPABLE
+	CALL	SCSI_CAP		; GET TOTAL BLOCKS IN DE:HL, BLOCK SIZE TO BC
+	LD	L,H			; DIVIDE BY 256 FOR # TRACKS
+	LD	H,E			; ... HIGH BYTE DISCARDED, RESULT IN HL
+	LD	D,16 | $80		; HEADS / CYL = 16, SET LBA CAPABILITY BIT
+	LD	E,16			; SECTORS / TRACK = 16
+	RET				; DONE, A STILL HAS SCSI_CAP STATUS
+;
+;=============================================================================
+; FUNCTION SUPPORT ROUTINES
+;=============================================================================
+;
+; ON RETURN, ZF SET INDICATES HARDWARE FOUND
+;
+SCSI_DETECT:
+	LD	A,$05
+	OUT	(SCSIBASE+3),A
+	IN	A,(SCSIBASE+3)
+	CP	$05
+	RET	NZ
+	LD	A,$0A
+	OUT	(SCSIBASE+3),A
+	IN	A,(SCSIBASE+3)
+	CP	$0A
+	RET
+;
+; INITIALIZE DEVICE
+;
+SCSI_INITDEV:
+	XOR	A
+	LD	(IY+SCSI_STAT),A
+	RET
+;
+;=============================================================================
+; COMMAND PROCESSING
+;=============================================================================
+;
+;----------------------------------------------------------------
+;WRITE LOGICAL BLOCK TO DISK
+;CUR_TID,CUR_LUN,CUR_LBN ALREADY SET
+;EXIT WITH ZERO STATUS IF OK
+;----------------------------------------------------------------
+;
+WR_PHY:
+	LD A,0AH		;WRITE COMMAND
+	JR PHY_COM		;FINISH SAME AS READ
+
+;----------------------------------------------------------------
+;READ LOGICAL BLOCK FROM DISK
+;CUR_TID,CUR_LUN,CUR_LBN ALREADY SET
+;EXIT WITH ZERO STATUS IF OK
+;----------------------------------------------------------------
+;
+RD_PHY:
+	LD A,8			;READ COMMAND
+PHY_COM:
+	LD (SCSI_S_CDB),A		;SET IN COMMAND BLOCK
+	LD IX,SCSI_S_IOT		;POINT TO IO TABLE
+	CALL SCSI_GO
+	AND 02H			;MASK TO ERROR BIT
+	RET
+;-------------------------------------------------------------------------------
+;DO SCSI TRANSACTION
+; IX=SCSI IO BLOCK
+;-------------------------------------------------------------------------------
+SCSI_GO:
+	LD A,$FF	;PRESET ERROR STATUS
+	LD L,(IX+4)	;POINT TO STATUS ADDRESS
+	LD H,(IX+5)	;POINT TO STATUS ADDRESS
+	LD (HL),A	;SET ERROR
+;
+	XOR A		;
+	OUT (SCSI_SR_MR),A	;RESET CONTROL REG
+	OUT (SCSI_SR_TCR),A	;CLEAR COMMAND REG.
+	OUT (SCSI_SR_ICR),A	;
+	LD A,(IX)	;GET TID
+	BIT	7,A	;   TURN ON MY ID
+	OUT (SCSI_SR_ODR),A	;SET TARGET ID
+	LD A,$01	;DRIVE BUS
+	OUT (SCSI_SR_ICR),A	;
+	LD A,$05	;SET SEL AND DRIVE BUS
+	OUT (SCSI_SR_ICR),A	;
+;
+;WAIT FOR SCSI BUSY
+	LD BC,0		;INIT TIMEOUT
+S_SWT:
+	IN A,(SCSI_SR_CSBS)	;GET BUS STATUS
+	AND SCSI_SM_BSY	;MASK TO BUSY BIT
+	JR NZ,S_BSYA	;JMP IF BUSY ACTIVE
+	NOP		;KILL A LITTLE TIME
+	NOP
+	NOP
+	NOP
+	DEC BC		;DEC TIMEOUT
+	LD A,B		;TEST TIMEOUT=0
+	OR C
+	JR NZ,S_SWT	;JMP IF NO TIMEOUT
+	XOR A		;CLEAR A
+	OUT (SCSI_SR_ICR),A	;CLEAR SEL AND DATA
+	JR S_EXIT	;ERROR EXIT
+;
+;BUSY IS ACTIVE
+S_BSYA:
+	XOR A		;CLEAR A
+	OUT (SCSI_SR_ICR),A	;CLEAR SEL AND DATA
+
+;-------------------------------------------------------------------------------
+;
+;TARGET IS SELECTED SO TEST BSY AND REQ
+;THEN DECODE REQUESTED PHASE
+;
+;-------------------------------------------------------------------------------
+PHASE:
+	XOR A
+	OUT (SCSI_SR_ICR),A	;RESET INITIATOR
+;
+S_WTREQ:
+	IN A,(SCSI_SR_CSBS)	;GET BUS STATUS
+	LD B,A		;SAVE COPY
+	AND SCSI_SM_BSY	;MASK TO BUSY BIT
+	JR NZ,S_WTRQ1	;STILL BUSY SO CONT.
+
+;-------------------------------------------------------------------------------
+;BUSY LOST SO EXIT
+;-------------------------------------------------------------------------------
+S_EXIT:
+	LD L,(IX+4)	;GET STATUS POINTER
+	LD H,(IX+5)	;GET STATUS POINTER
+	LD A,(HL)
+	RET		;BUSY LOST? WERE DONE
+;
+S_WTRQ1:
+	LD A,B		;RECOVER STATUS
+	AND SCSI_SM_REQ	;REQUEST ACTIVE?
+	JR Z,S_WTREQ	;LOOP TILL REQUEST
+
+;-------------------------------------------------------------------------------
+;REQUEST IS ACTIVE SO SET 5380 TO REQUESTED PHASE
+;-------------------------------------------------------------------------------
+	LD A,B		;RECOVER BUS STATUS
+	RR A		;SHIFT STATUS TO PHASE BITS
+	RR A
+	AND $07		;MASK TO PHASE BITS
+	OUT (SCSI_SR_TCR),A	;SET PHASE
+;
+;JUMP TO PHASE HANDLER
+;
+	LD A,B		;RECOVER BUS STATUS 
+	RR A
+	AND $0E		;MASK TO PHASE BITS
+	LD E,A		;
+	LD D,0
+	LD HL,PHTABL	;POINT TO TABLE
+	ADD HL,DE	;OFFSET INTO TABLE
+	LD E,(HL)	;GET EXECUTION ADDRESS
+	INC HL
+	LD D,(HL)
+	PUSH DE
+	RET		;EXECUTE PHASE
+
+;-------------------------------------------------------------------------------
+;PHASE TABLE
+;-------------------------------------------------------------------------------
+PHTABL:
+	.WORD	PHASE0	;DATA OUT
+	.WORD	PHASE1	;DATA IN
+	.WORD	PHASE2	;CMD OUT
+	.WORD	PHASE3	;STATUS IN
+	.WORD	S_EXIT	;UNUSED
+	.WORD	S_EXIT	;UNUSED
+	.WORD	PHASE6	;MESSAGE OUT
+	.WORD	PHASE7	;MESSAGE IN
+
+;-------------------------------------------------------------------------------
+;PHASE HANDLERS
+;-------------------------------------------------------------------------------
+;
+;DATA OUT
+PHASE0:
+	LD L,(IX+6)	;GET POINTER
+	LD H,(IX+7)
+	JP S_WRIT	;WRITE BYTES
+;
+;DATA IN
+PHASE1:
+	LD L,(IX+8)	;GET POINTER
+	LD H,(IX+9)
+	JP S_READ	;READ BYTES
+;
+;CMD OUT
+PHASE2:
+	LD L,(IX+2)
+	LD H,(IX+3)
+	JP S_WRIT
+;
+;STATUS IN
+PHASE3:
+	LD L,(IX+4)
+	LD H,(IX+5)
+	JP S_READ
+;
+;MSG OUT
+PHASE6:
+	LD L,(IX+10)
+	LD H,(IX+11)
+	JP S_WRIT
+;
+;MSG IN
+PHASE7:
+	LD L,(IX+12)
+	LD H,(IX+13)
+	JP S_READ
+;-------------------------------------------------------------------------------
+;SCSI WRITE ROUTINE (SEND BYTES TO TARGET)
+;BUS PHASE ALREADY SET. RETURN ON PHASE MISMATCH 
+;-------------------------------------------------------------------------------
+S_WRIT:
+	LD A,1		;DRIVE SCSI DATA BUS
+	OUT (SCSI_SR_ICR),A
+;
+;WAIT FOR REQ WHILE CHECKING BUSY
+;
+S_WWREQ:
+        IN A,(SCSI_SR_CSBS)  ;GET CURRENT BUS STAT
+        LD B,A          ;SAVE IT
+        AND SCSI_SM_REQ      ;REQUEST ACTIVE?
+        JR NZ,S_WNXT    ;
+;
+        LD A,B          ;RECOVER CURRENT BUS STAT
+        AND SCSI_SM_BSY      ;STILL BUSY?
+        JP NZ,S_WWREQ   ;LOOP IF STILL BUSY
+        JP PHASE        ;
+;
+;REQUEST ACTIVE SO CHECK PHASE
+;
+S_WNXT:
+        IN A,(SCSI_SR_BSR)   ;GET STATUS
+        AND SCSI_SM_PHM      ;MASK TO PHASE MATCH
+        JP Z,PHASE      ;JMP IF PHASE MISMATCH
+;
+;REQUEST ACTIVE AND PHASE MATCH SO SEND DATA
+;
+	LD A,(HL)	;GET BYTE
+	OUT (SCSI_SR_ODR),A	;SEND DATA
+	LD A,$11	;ACK + DRIVE BUS
+	OUT (SCSI_SR_ICR),A	;SET ACK,DRIVE SCSI BUS
+	INC HL		;ADVANCE BUF POINTER
+;
+;WAIT FOR REQUEST TO DROP
+;
+S_WNREQ:
+	IN A,(SCSI_SR_CSBS)	;GET CURRENT STATUS
+	AND SCSI_SM_REQ
+	JR NZ,S_WNREQ	;LOOP TILL REQ DROPS
+;
+	LD A,$1		;DROP ACK,ASSERT DATA
+	OUT (SCSI_SR_ICR),A	;DROP ACK
+	JP S_WWREQ	;LOOP FOR NEXT BYTE/PHASE
+;-------------------------------------------------------------------------------
+;SCSI READ ROUTINE (GET BYTES FROM TARGET)
+;BUS PHASE ALREADY SET. RETURN ON PHASE MISMATCH 
+;-------------------------------------------------------------------------------
+;
+S_READ:
+;
+;WAIT FOR REQ WHILE CHECKING BUSY
+;
+S_RWREQ:
+        IN A,(SCSI_SR_CSBS)  ;GET CURRENT BUS STAT
+        LD B,A          ;SAVE IT
+        AND SCSI_SM_REQ      ;REQUEST ACTIVE?
+        JR NZ,S_RNXT    ;
+;
+        LD A,B          ;RECOVER CURRENT BUS STAT
+        AND SCSI_SM_BSY      ;STILL BUSY?
+        JP NZ,S_RWREQ   ;LOOP IF STIL BUSY
+        JP PHASE        ;
+;
+;REQUEST ACTIVE SO CHECK PHASE
+S_RNXT:
+        IN A,(SCSI_SR_BSR)   ;GET STATUS
+        AND SCSI_SM_PHM      ;MASK TO PHASE MATCH
+        JP Z,PHASE      ;JMP IF PHASE MISMATCH
+
+;REQUEST ACTIVE AND PHASE MATCH SO GET DATA
+;
+	IN A, (SCSI_SR_CSD)	;GET DATA
+	LD (HL),A	;SAVE DATA
+	LD A,$10
+	OUT (SCSI_SR_ICR),A	;SET ACK
+	INC HL		;ADVANCE BUF POINTER
+;
+;WAIT FOR REQUEST TO DROP
+;
+S_RNREQ:
+	IN A,(SCSI_SR_CSBS)	;GET CURRENT STATUS
+	AND SCSI_SM_REQ
+	JR NZ,S_RNREQ	;LOOP TILL REQ DROPS
+	XOR A
+	OUT (SCSI_SR_ICR),A	;DROP ACK
+	JP S_READ	;LOOP FOR NEXT BYTE/PHASE
+
+;
+;=============================================================================
+; HARDWARE INTERFACE ROUTINES
+;=============================================================================
+;
+;=============================================================================
+; ERROR HANDLING AND DIAGNOSTICS
+;=============================================================================
+;
+; ERROR HANDLERS
+;
+SCSI_NOMEDIA:
+	LD	A,SCSI_STNOMEDIA
+	JR	SCSI_ERR
+;
+SCSI_IOERR:
+	LD	A,SCSI_STIOERR
+	JR	SCSI_ERR
+;
+SCSI_TO:
+	LD	A,SCSI_STTO
+	JR	SCSI_ERR
+;
+SCSI_NOTRDY:
+	LD	A,SCSI_STNOTRDY
+	JR	SCSI_ERR
+;
+SCSI_ERR:
+	LD	(IY+SCSI_STAT),A	; SAVE NEW STATUS
+;
+#IF (SCSITRACE >= 2)
+	CALL	SCSI_PRTSTAT
+#ENDIF
+	OR	A			; SET FLAGS
+	RET
+;
+;
+;
+SCSI_PRTERR:
+	RET	Z			; DONE IF NO ERRORS
+	; FALL THRU TO SCSI_PRTSTAT
+;
+; PRINT FULL DEVICE STATUS LINE
+;
+SCSI_PRTSTAT:
+	PUSH	AF
+	PUSH	DE
+	PUSH	HL
+	LD	A,(IY+SCSI_STAT)
+	CALL	SCSI_PRTPREFIX		; PRINT UNIT PREFIX
+	JR	SCSI_PRTSTAT3
+SCSI_PRTSTAT2:
+	CALL	NEWLINE
+	PRTS("SCSI:$")			; NO UNIT NUM IN PREFIX FOR INVALID UNIT
+SCSI_PRTSTAT3:
+	CALL	PC_SPACE		; FORMATTING
+	CALL	SCSI_PRTSTATSTR
+	POP	HL
+	POP	DE
+	POP	AF
+	RET
+;
+; PRINT STATUS STRING
+;
+SCSI_PRTSTATSTR:
+	PUSH	AF
+	PUSH	DE
+	LD	A,(IY+SCSI_STAT)
+	OR	A
+	LD	DE,SCSI_STR_STOK
+	JR	Z,SCSI_PRTSTATSTR1
+	INC	A
+	LD	DE,SCSI_STR_STNOMEDIA
+	JR	Z,SCSI_PRTSTATSTR1
+	INC	A
+	LD	DE,SCSI_STR_STIOERR
+	JR	Z,SCSI_PRTSTATSTR1
+	INC	A
+	LD	DE,SCSI_STR_STTO
+	JR	Z,SCSI_PRTSTATSTR1
+	INC	A
+	LD	DE,SCSI_STR_STNOTRDY
+	JR	Z,SCSI_PRTSTATSTR1
+	LD	DE,SCSI_STR_STUNK
+SCSI_PRTSTATSTR1:
+	CALL	WRITESTR
+	POP	DE
+	POP	AF
+	RET
+;
+; PRINT DIAGNONSTIC PREFIX
+;
+SCSI_PRTPREFIX:	
+	PUSH	AF
+	CALL	NEWLINE
+	PRTS("SCSI$")
+	LD	A,(IY+SCSI_DEV)		; GET CURRENT DEVICE NUM
+	CP	$FE			; NOT YET ASSIGNED?
+	JR	Z,SCSI_PRTPREFIX1	; SKIP DEV NUM IF SO
+	CALL	PRTDECB
+SCSI_PRTPREFIX1:
+	CALL	PC_COLON
+	POP	AF
+	RET
+;
+;=============================================================================
+; STRING DATA
+;=============================================================================
+;
+SCSI_STR_STOK		.TEXT	"OK$"
+SCSI_STR_STNOMEDIA	.TEXT	"NO MEDIA$"
+SCSI_STR_STIOERR	.TEXT	"IO ERROR$"
+SCSI_STR_STTO		.TEXT	"TIMEOUT$"
+SCSI_STR_STNOTRDY	.TEXT	"NOT READY$"
+SCSI_STR_STUNK		.TEXT	"UNKNOWN ERROR$"
+;
+;=============================================================================
+; DATA STORAGE
+;=============================================================================
+;
+SCSI_DEVNUM	.DB	0		; TEMP DEVICE NUM USED DURING INIT
+SCSI_DSKBUF	.DW	0		; ACTIVE DISK BUFFER
+;
+;----------------------------------------------------------------
+;SCSI COMMAND DESCRIPTOR FOR READ/WRITE
+;DO NOT USE THIS FOR DIRECT SCSI I/O
+;YOU WILL MESS UP BLOCK/DEBLOCK
+;
+SCSI_S_CDB:	
+		.DB	8		; COMMAND
+SCSI_CUR_LUN:
+		.DB	0 << 5		; LUN/LBA HI
+SCSI_CUR_LBN:
+		.DB	0		; LBA MID
+		.DB	0		; LBA LOW
+		.DB	1		; COUNT
+		.DB	0		; FLAGS
+;
+;----------------------------------------------------------------
+;SCSI I/O ADDRESS TABLE	FOR READ/WRITE
+;DONT MESS WITH THIS EITHER
+SCSI_S_IOT:
+SCSI_CUR_TID	.DB	1 << SCSI_TID	;TARGET
+		.DB	0		;UNUSED
+		.DW	SCSI_S_CDB	;CDB POINTER
+		.DW	SCSI_S_STAT	;STATUS POINTER
+SCSI_BUF_OUT	.DW	HB_WRKBUF	;DATA OUT POINTER
+SCSI_BUF_IN	.DW	HB_WRKBUF	;DATA IN POINTER
+		.DW	SCSI_S_MSG	;MSG OUT POINTER
+		.DW	SCSI_S_MSG	;MSG IN POINTER
+;
+;----------------------------------------------------------------
+;THIS IS THE END OF INITIALIZED DATA
+;EVERYTHING FOLLOWING MUST HAVE MEMORY SPACE AVAILABLE
+;BUT IS NOT PART OF THE BOOT IMAGE
+;----------------------------------------------------------------
+;
+; UNINITIALIZED	DATA AREA
+;
+SCSI_S_STAT	.DW	0	;SCSI ENDING STATUS
+SCSI_S_MSG	.DW	0	;SCSI MESSAGE
+;
diff --git a/Source/ver.inc b/Source/ver.inc
index 6768e9d3..ab3717be 100644
--- a/Source/ver.inc
+++ b/Source/ver.inc
@@ -2,7 +2,7 @@
 #DEFINE	RMN	6
 #DEFINE	RUP	0
 #DEFINE	RTP	0
-#DEFINE BIOSVER	"3.6.0-dev.43"
+#DEFINE BIOSVER	"3.6.0-dev.44"
 #define rmj	RMJ
 #define rmn	RMN
 #define rup	RUP
diff --git a/Source/ver.lib b/Source/ver.lib
index 7a815ab0..d6ff2e4d 100644
--- a/Source/ver.lib
+++ b/Source/ver.lib
@@ -3,5 +3,5 @@ rmn	equ	6
 rup	equ	0
 rtp	equ	0
 biosver	macro
-	db	"3.6.0-dev.43"
+	db	"3.6.0-dev.44"
 	endm