IMM Driver Cleanup, PPA Driver Skeleton

IMM Driver has rational timeouts now. It also lights the MG014 LED during activity. The PPA skeleton just attempts to determine if the PPA interface is present. It does not attempt any I/O.
Preliminary IMM Driver (Zip Drive)
2026-02-07 23:13:13 -06:00 · 2023-05-26 16:48:13 -07:00 · 2023-05-23 18:35:18 -07:00 · 2023-05-11 14:20:54 -07:00
48 changed files with 2700 additions and 33 deletions
--- a/Doc/ChangeLog.txt
+++ b/Doc/ChangeLog.txt
@@ -7,6 +7,7 @@ Version 3.3
 - WBW: Support per-drive floppy configuration
 - WBW: Support for Bill Shen's VGARC
 - WBW: Support for MG014 Parallel Port module + printer
+- WBW: Support for Zip Drive on emm interface (much inspiration from Alan Cox)

 Version 3.2.1
 -------------
--- a/Applications.pdf
+++ b/Applications.pdf
--- a/Catalog.pdf
+++ b/Catalog.pdf
--- a/Errata.pdf
+++ b/Errata.pdf
--- a/Applications.pdf
+++ b/Applications.pdf
--- a/Doc/RomWBW
+++ b/Doc/RomWBW
--- a/Doc/RomWBW
+++ b/Doc/RomWBW
--- a/Options.pdf
+++ b/Options.pdf
--- a/ReadMe.md
+++ b/ReadMe.md
@@ -3,7 +3,7 @@
 **RomWBW ReadMe** \
 Version 3.3 \
 Wayne Warthen  ([wwarthen@gmail.com](mailto:wwarthen@gmail.com)) \
-03 May 2023
+23 May 2023

 # Overview

--- a/ReadMe.txt
+++ b/ReadMe.txt
@@ -1,6 +1,6 @@
 RomWBW ReadMe
 Wayne Warthen (wwarthen@gmail.com)
-03 May 2023
+23 May 2023



--- a/Source/Apps/assign.asm
+++ b/Source/Apps/assign.asm
@@ -1918,8 +1918,8 @@ dev06	.db	"SD",0
 dev07	.db	"PRPSD",0
 dev08	.db	"PPPSD",0
 dev09	.db	"HDSK",0
-dev10	.equ	devunk
-dev11	.equ	devunk
+dev10	.db	"PPA",0
+dev11	.db	"IMM",0
 dev12	.equ	devunk
 dev13	.equ	devunk
 dev14	.equ	devunk
--- a/Source/CBIOS/cbios.asm
+++ b/Source/CBIOS/cbios.asm
@@ -2929,6 +2929,12 @@ DRV_INIT3:
 	RET
 ;
 DRV_INIT3A:
+	; CHECK FOR HARD DISK REMOVABLE CARTRIDGE DRIVES
+	CP	DIODEV_PPA		; PPA (ZIP DRIVE) IS REMOVABLE
+	JR	Z,DRV_INIT3B		; IF SO, SKIP MEDIA CHECK
+	CP	DIODEV_IMM		; IMM (ZIP DRIVE) IS REMOVABLE
+	JR	Z,DRV_INIT3B		; IF SO, SKIP MEDIA CHECK
+
 	; CHECK FOR ACTIVE AND RETURN IF NOT
 	PUSH	DE			; SAVE DE (HARD DISK VOLUME COUNTER)
 	PUSH	HL			; SAVE DRIVE LIST PTR
@@ -2944,6 +2950,7 @@ DRV_INIT3A:

 	RET	NZ			; IF NO MEDIA, JUST RETURN

+DRV_INIT3B:
 	; IF ACTIVE...
 	LD	(HL),C			; SAVE UNIT NUM IN LIST
 	INC	HL			; BUMP PTR
@@ -3392,8 +3399,8 @@ DEV06	.DB	"SD$"
 DEV07	.DB	"PRPSD$"
 DEV08	.DB	"PPPSD$"
 DEV09	.DB	"HDSK$"
-DEV10	.EQU	DEVUNK
-DEV11	.EQU	DEVUNK
+DEV10	.DB	"PPA$"
+DEV11	.DB	"IMM$"
 DEV12	.EQU	DEVUNK
 DEV13	.EQU	DEVUNK
 DEV14	.EQU	DEVUNK
--- a/Source/CPM3/boot.z80
+++ b/Source/CPM3/boot.z80
@@ -181,6 +181,12 @@ dinit3:
 	ret
 ;
 dinit3a:
+	; check for hard disk removable cartridge drives
+	cp	0A0h			; ppa (zip drive) is removable
+	jr	z,dinit3b		; if so, skip media check
+	cp	0B0h			; imm (zip drive) is removable
+	jr	z,dinit3b		; if so, skip media check
+
 	; check for active and return if not
 	push	de			; save de (hard disk volume counter)
 	push	hl			; save drive list ptr
@@ -195,7 +201,8 @@ dinit3a:
 	pop	de			; restore de
 	
 	ret	nz			; if no media, just return
-	
+
+dinit3b:
 	; if active...
 	ld	(hl),c			; save unit num in list
 	inc	hl			; bump ptr
--- a/Source/Doc/Applications.md
+++ b/Source/Doc/Applications.md
@@ -889,6 +889,28 @@ written in C and requires SDCC to compile. As such it is not part of
 the RomWBW build process. However, the full project and source code is
 found in the [FAT GitHub Repository](https://github.com/wwarthen/FAT).

+## Known Issues
+
+CP/M (and workalike) OSes have significant restrictions on filename
+characters.  The FAT application will block any attempt to create a
+file on the CP/M filesystem containing any of these prohibited
+characters:
+
+|         `< > . , ; : = ? * [ ] _ % | ( ) / \`
+
+The operation will be aborted with "`Error: Invalid Path Name`" if such
+a filename character is encountered.
+
+Since MS-DOS does allow some of these characters, you can have
+issues when copying files from MS-DOS to CP/M if the MS-DOS filenames
+use these characters.  Unfortunately, FAT is not yet smart enough to
+substitute illegal characters with legal ones.  So, you will need to
+clean the filenames before trying to copy them to CP/M.
+
+The FAT application does try to detect the scenario where you are
+copying a file to itself.  However, this detection is not perfect and
+can corrupt a file if it occurs.  Be careful to avoid this.
+
 `\clearpage`{=latex}

 # TUNE
--- a/Source/Doc/UserGuide.md
+++ b/Source/Doc/UserGuide.md
@@ -3896,7 +3896,8 @@ may be discovered by RomWBW in your system.
 | DSKY      | System   | Keypad & Display                                       |
 | DSRTC     | RTC      | Maxim DS1302 Real-Time Clock w/ NVRAM                  |
 | DUART     | Char     | SCC2681 or compatible Dual UART                        |
-| FD        | Disk     | 8272 of compatible Floppy Disk Controller              |
+| EMM       | Disk     | Disk drive on Parallel Port emm interface (Zip Drive)  |
+| FD        | Disk     | 8272 or compatible Floppy Disk Controller              |
 | GDC       | Video    | uPD7220 Video Display Controller                       |
 | HDSK      | Disk     | SIMH Simulator Hard Disk                               |
 | IDE       | Disk     | IDE/ATA Hard Disk Interface                            |
--- a/Source/Doc/Z180
+++ b/Source/Doc/Z180
--- a/Source/HBIOS/Config/RCZ80_easy.asm
+++ b/Source/HBIOS/Config/RCZ80_easy.asm
@@ -75,5 +75,6 @@ IDEENABLE	.SET	TRUE		; IDE: ENABLE IDE DISK DRIVER (IDE.ASM)
 PPIDEENABLE	.SET	TRUE		; PPIDE: ENABLE PARALLEL PORT IDE DISK DRIVER (PPIDE.ASM)
 SDENABLE	.SET	FALSE		; SD: ENABLE SD CARD DISK DRIVER (SD.ASM)
 SDCNT		.SET	1		; SD: NUMBER OF SD CARD DEVICES (1-2), FOR DSD/SC/MT SC ONLY
+IMMENABLE	.SET	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
 ;
 PRPENABLE	.SET	FALSE		; PRP: ENABLE ECB PROPELLER IO BOARD DRIVER (PRP.ASM)
--- a/Source/HBIOS/Config/RCZ80_kio.asm
+++ b/Source/HBIOS/Config/RCZ80_kio.asm
@@ -72,5 +72,6 @@ IDEENABLE	.SET	TRUE		; IDE: ENABLE IDE DISK DRIVER (IDE.ASM)
 PPIDEENABLE	.SET	TRUE		; PPIDE: ENABLE PARALLEL PORT IDE DISK DRIVER (PPIDE.ASM)
 SDENABLE	.SET	FALSE		; SD: ENABLE SD CARD DISK DRIVER (SD.ASM)
 SDCNT		.SET	1		; SD: NUMBER OF SD CARD DEVICES (1-2), FOR DSD/SC/MT SC ONLY
+IMMENABLE	.SET	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
 ;
 PRPENABLE	.SET	FALSE		; PRP: ENABLE ECB PROPELLER IO BOARD DRIVER (PRP.ASM)
--- a/Source/HBIOS/Config/RCZ80_skz.asm
+++ b/Source/HBIOS/Config/RCZ80_skz.asm
@@ -67,5 +67,6 @@ IDEENABLE	.SET	TRUE		; IDE: ENABLE IDE DISK DRIVER (IDE.ASM)
 PPIDEENABLE	.SET	TRUE		; PPIDE: ENABLE PARALLEL PORT IDE DISK DRIVER (PPIDE.ASM)
 SDENABLE	.SET	FALSE		; SD: ENABLE SD CARD DISK DRIVER (SD.ASM)
 SDCNT		.SET	1		; SD: NUMBER OF SD CARD DEVICES (1-2), FOR DSD/SC/MT SC ONLY
+IMMENABLE	.SET	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
 ;
 PRPENABLE	.SET	FALSE		; PRP: ENABLE ECB PROPELLER IO BOARD DRIVER (PRP.ASM)
--- a/Source/HBIOS/Config/RCZ80_std.asm
+++ b/Source/HBIOS/Config/RCZ80_std.asm
@@ -61,5 +61,6 @@ PPIDEENABLE	.SET	TRUE		; PPIDE: ENABLE PARALLEL PORT IDE DISK DRIVER (PPIDE.ASM)
 SDENABLE	.SET	FALSE		; SD: ENABLE SD CARD DISK DRIVER (SD.ASM)
 SDMODE		.SET	SDMODE_PIO	; SD: DRIVER MODE: SDMODE_[JUHA|N8|CSIO|PPI|UART|DSD|MK4|SC|MT|PIO|USR]
 SDCNT		.SET	1		; SD: NUMBER OF SD CARD DEVICES (1-2), FOR DSD/SC/MT SC ONLY
+IMMENABLE	.SET	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
 ;
 PRPENABLE	.SET	FALSE		; PRP: ENABLE ECB PROPELLER IO BOARD DRIVER (PRP.ASM)
--- a/Source/HBIOS/Config/RCZ80_tiny.asm
+++ b/Source/HBIOS/Config/RCZ80_tiny.asm
@@ -82,5 +82,6 @@ IDE0BASE	.SET	$90		; IDE 0: IO BASE ADDRESS
 PPIDEENABLE	.SET	TRUE		; PPIDE: ENABLE PARALLEL PORT IDE DISK DRIVER (PPIDE.ASM)
 SDENABLE	.SET	FALSE		; SD: ENABLE SD CARD DISK DRIVER (SD.ASM)
 SDCNT		.SET	1		; SD: NUMBER OF SD CARD DEVICES (1-2), FOR DSD/SC/MT SC ONLY
+IMMENABLE	.SET	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
 ;
 PRPENABLE	.SET	FALSE		; PRP: ENABLE ECB PROPELLER IO BOARD DRIVER (PRP.ASM)
--- a/Source/HBIOS/Config/RCZ80_zrc.asm
+++ b/Source/HBIOS/Config/RCZ80_zrc.asm
@@ -59,5 +59,6 @@ IDEENABLE	.SET	TRUE		; IDE: ENABLE IDE DISK DRIVER (IDE.ASM)
 PPIDEENABLE	.SET	TRUE		; PPIDE: ENABLE PARALLEL PORT IDE DISK DRIVER (PPIDE.ASM)
 SDENABLE	.SET	FALSE		; SD: ENABLE SD CARD DISK DRIVER (SD.ASM)
 SDCNT		.SET	1		; SD: NUMBER OF SD CARD DEVICES (1-2), FOR DSD/SC/MT SC ONLY
+IMMENABLE	.SET	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
 ;
 PRPENABLE	.SET	FALSE		; PRP: ENABLE ECB PROPELLER IO BOARD DRIVER (PRP.ASM)
--- a/Source/HBIOS/Config/RCZ80_zrc_ram.asm
+++ b/Source/HBIOS/Config/RCZ80_zrc_ram.asm
@@ -63,5 +63,6 @@ IDEENABLE	.SET	TRUE		; IDE: ENABLE IDE DISK DRIVER (IDE.ASM)
 PPIDEENABLE	.SET	TRUE		; PPIDE: ENABLE PARALLEL PORT IDE DISK DRIVER (PPIDE.ASM)
 SDENABLE	.SET	FALSE		; SD: ENABLE SD CARD DISK DRIVER (SD.ASM)
 SDCNT		.SET	1		; SD: NUMBER OF SD CARD DEVICES (1-2), FOR DSD/SC/MT SC ONLY
+IMMENABLE	.SET	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
 ;
 PRPENABLE	.SET	FALSE		; PRP: ENABLE ECB PROPELLER IO BOARD DRIVER (PRP.ASM)
--- a/Source/HBIOS/cfg_dyno.asm
+++ b/Source/HBIOS/cfg_dyno.asm
@@ -252,6 +252,10 @@ PIO1BASE	.EQU	$BC		; PIO 1: REGISTERS BASE ADR
 ;
 LPTENABLE	.EQU	FALSE		; LPT: ENABLE CENTRONICS PRINTER DRIVER (LPT.ASM)
 ;
+PPAENABLE	.EQU	FALSE		; PPA: ENABLE PPA DISK DRIVER (PPA.ASM)
+;
+IMMENABLE	.EQU	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
+;
 PIO_4P		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
--- a/Source/HBIOS/cfg_master.asm
+++ b/Source/HBIOS/cfg_master.asm
@@ -317,6 +317,22 @@ LPTTRACE	.EQU	1		; LPT: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
 LPT0BASE	.EQU	$E8		; LPT 0: REGISTERS BASE ADR
 LPT1BASE	.EQU	$EC		; LPT 1: REGISTERS BASE ADR
 ;
+PPAENABLE	.EQU	FALSE		; PPA: ENABLE PPA DISK DRIVER (PPA.ASM)
+PPACNT		.EQU	1		; PPA: NUMBER OF PPA DEVICES (1-2)
+PPATRACE	.EQU	1		; PPA: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
+PPA0MODE	.EQU	PPAMODE_MG014	; PPA 0: DRIVER MODE: PPAMODE_[NONE|MG014]
+PPA0BASE	.EQU	LPT0BASE	; PPA 0: BASE I/O ADDRESS OF PPI FOR PPA
+PPA1MODE	.EQU	PPAMODE_MG014	; PPA 1: DRIVER MODE: PPAMODE_[NONE|MG014]
+PPA1BASE	.EQU	LPT1BASE	; PPA 1: BASE I/O ADDRESS OF PPI FOR PPA
+;
+IMMENABLE	.EQU	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
+IMMCNT		.EQU	1		; IMM: NUMBER OF IMM DEVICES (1-2)
+IMMTRACE	.EQU	1		; IMM: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
+IMM0MODE	.EQU	IMMMODE_MG014	; IMM 0: DRIVER MODE: IMMMODE_[NONE|MG014]
+IMM0BASE	.EQU	LPT0BASE	; IMM 0: BASE I/O ADDRESS OF PPI FOR IMM
+IMM1MODE	.EQU	IMMMODE_MG014	; IMM 1: DRIVER MODE: IMMMODE_[NONE|MG014]
+IMM1BASE	.EQU	LPT1BASE	; IMM 1: BASE I/O ADDRESS OF PPI FOR IMM
+;
 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)
--- a/Source/HBIOS/cfg_mbc.asm
+++ b/Source/HBIOS/cfg_mbc.asm
@@ -241,6 +241,22 @@ LPTTRACE	.EQU	1		; LPT: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
 LPT0BASE	.EQU	$E8		; LPT 0: REGISTERS BASE ADR
 LPT1BASE	.EQU	$EC		; LPT 1: REGISTERS BASE ADR
 ;
+PPAENABLE	.EQU	FALSE		; PPA: ENABLE PPA DISK DRIVER (PPA.ASM)
+PPACNT		.EQU	1		; PPA: NUMBER OF PPA DEVICES (1-2)
+PPATRACE	.EQU	1		; PPA: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
+PPA0MODE	.EQU	PPAMODE_MG014	; PPA 0: DRIVER MODE: PPAMODE_[NONE|MG014]
+PPA0BASE	.EQU	LPT0BASE	; PPA 0: BASE I/O ADDRESS OF PPI FOR PPA
+PPA1MODE	.EQU	PPAMODE_MG014	; PPA 1: DRIVER MODE: PPAMODE_[NONE|MG014]
+PPA1BASE	.EQU	LPT1BASE	; PPA 1: BASE I/O ADDRESS OF PPI FOR PPA
+;
+IMMENABLE	.EQU	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
+IMMCNT		.EQU	1		; IMM: NUMBER OF IMM DEVICES (1-2)
+IMMTRACE	.EQU	1		; IMM: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
+IMM0MODE	.EQU	IMMMODE_MG014	; IMM 0: DRIVER MODE: IMMMODE_[NONE|MG014]
+IMM0BASE	.EQU	LPT0BASE	; IMM 0: BASE I/O ADDRESS OF PPI FOR IMM
+IMM1MODE	.EQU	IMMMODE_MG014	; IMM 1: DRIVER MODE: IMMMODE_[NONE|MG014]
+IMM1BASE	.EQU	LPT1BASE	; IMM 1: BASE I/O ADDRESS OF PPI FOR IMM
+;
 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)
--- a/Source/HBIOS/cfg_mk4.asm
+++ b/Source/HBIOS/cfg_mk4.asm
@@ -254,6 +254,10 @@ LPTTRACE	.EQU	1		; LPT: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
 LPT0BASE	.EQU	$E8		; LPT 0: REGISTERS BASE ADR
 LPT1BASE	.EQU	$EC		; LPT 1: REGISTERS BASE ADR
 ;
+PPAENABLE	.EQU	FALSE		; PPA: ENABLE PPA DISK DRIVER (PPA.ASM)
+;
+IMMENABLE	.EQU	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
+;
 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)
--- a/Source/HBIOS/cfg_n8.asm
+++ b/Source/HBIOS/cfg_n8.asm
@@ -247,6 +247,10 @@ PIO1BASE	.EQU	$BC		; PIO 1: REGISTERS BASE ADR
 ;
 LPTENABLE	.EQU	FALSE		; LPT: ENABLE CENTRONICS PRINTER DRIVER (LPT.ASM)
 ;
+PPAENABLE	.EQU	FALSE		; PPA: ENABLE PPA DISK DRIVER (PPA.ASM)
+;
+IMMENABLE	.EQU	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
+;
 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)
--- a/Source/HBIOS/cfg_rcz180.asm
+++ b/Source/HBIOS/cfg_rcz180.asm
@@ -263,6 +263,22 @@ LPTTRACE	.EQU	1		; LPT: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
 LPT0BASE	.EQU	$18		; LPT 0: REGISTERS BASE ADR
 LPT1BASE	.EQU	$00		; LPT 1: REGISTERS BASE ADR
 ;
+PPAENABLE	.EQU	FALSE		; PPA: ENABLE PPA DISK DRIVER (PPA.ASM)
+PPACNT		.EQU	1		; PPA: NUMBER OF PPA DEVICES (1-2)
+PPATRACE	.EQU	1		; PPA: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
+PPA0MODE	.EQU	PPAMODE_MG014	; PPA 0: DRIVER MODE: PPAMODE_[NONE|MG014]
+PPA0BASE	.EQU	LPT0BASE	; PPA 0: BASE I/O ADDRESS OF PPI FOR PPA
+PPA1MODE	.EQU	PPAMODE_MG014	; PPA 1: DRIVER MODE: PPAMODE_[NONE|MG014]
+PPA1BASE	.EQU	LPT1BASE	; PPA 1: BASE I/O ADDRESS OF PPI FOR PPA
+;
+IMMENABLE	.EQU	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
+IMMCNT		.EQU	1		; IMM: NUMBER OF IMM DEVICES (1-2)
+IMMTRACE	.EQU	1		; IMM: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
+IMM0MODE	.EQU	IMMMODE_MG014	; IMM 0: DRIVER MODE: IMMMODE_[NONE|MG014]
+IMM0BASE	.EQU	LPT0BASE	; IMM 0: BASE I/O ADDRESS OF PPI FOR IMM
+IMM1MODE	.EQU	IMMMODE_MG014	; IMM 1: DRIVER MODE: IMMMODE_[NONE|MG014]
+IMM1BASE	.EQU	LPT1BASE	; IMM 1: BASE I/O ADDRESS OF PPI FOR IMM
+;
 PIO_4P		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
--- a/Source/HBIOS/cfg_rcz280.asm
+++ b/Source/HBIOS/cfg_rcz280.asm
@@ -267,6 +267,22 @@ LPTTRACE	.EQU	1		; LPT: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
 LPT0BASE	.EQU	$18		; LPT 0: REGISTERS BASE ADR
 LPT1BASE	.EQU	$00		; LPT 1: REGISTERS BASE ADR
 ;
+PPAENABLE	.EQU	FALSE		; PPA: ENABLE PPA DISK DRIVER (PPA.ASM)
+PPACNT		.EQU	1		; PPA: NUMBER OF PPA DEVICES (1-2)
+PPATRACE	.EQU	1		; PPA: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
+PPA0MODE	.EQU	PPAMODE_MG014	; PPA 0: DRIVER MODE: PPAMODE_[NONE|MG014]
+PPA0BASE	.EQU	LPT0BASE	; PPA 0: BASE I/O ADDRESS OF PPI FOR PPA
+PPA1MODE	.EQU	PPAMODE_MG014	; PPA 1: DRIVER MODE: PPAMODE_[NONE|MG014]
+PPA1BASE	.EQU	LPT1BASE	; PPA 1: BASE I/O ADDRESS OF PPI FOR PPA
+;
+IMMENABLE	.EQU	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
+IMMCNT		.EQU	1		; IMM: NUMBER OF IMM DEVICES (1-2)
+IMMTRACE	.EQU	1		; IMM: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
+IMM0MODE	.EQU	IMMMODE_MG014	; IMM 0: DRIVER MODE: IMMMODE_[NONE|MG014]
+IMM0BASE	.EQU	LPT0BASE	; IMM 0: BASE I/O ADDRESS OF PPI FOR IMM
+IMM1MODE	.EQU	IMMMODE_MG014	; IMM 1: DRIVER MODE: IMMMODE_[NONE|MG014]
+IMM1BASE	.EQU	LPT1BASE	; IMM 1: BASE I/O ADDRESS OF PPI FOR IMM
+;
 PIO_4P		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
--- a/Source/HBIOS/cfg_rcz80.asm
+++ b/Source/HBIOS/cfg_rcz80.asm
@@ -258,9 +258,25 @@ LPTENABLE	.EQU	FALSE		; LPT: ENABLE CENTRONICS PRINTER DRIVER (LPT.ASM)
 LPTMODE		.EQU	LPTMODE_MG014	; LPT: DRIVER MODE: LPTMODE_[NONE|IBM|MG014]
 LPTCNT		.EQU	1		; LPT: NUMBER OF CHIPS TO DETECT (1-2)
 LPTTRACE	.EQU	1		; LPT: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
-LPT0BASE	.EQU	$18		; LPT 0: REGISTERS BASE ADR
+LPT0BASE	.EQU	$0C		; LPT 0: REGISTERS BASE ADR
 LPT1BASE	.EQU	$00		; LPT 1: REGISTERS BASE ADR
 ;
+PPAENABLE	.EQU	FALSE		; PPA: ENABLE PPA DISK DRIVER (PPA.ASM)
+PPACNT		.EQU	1		; PPA: NUMBER OF PPA DEVICES (1-2)
+PPATRACE	.EQU	1		; PPA: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
+PPA0MODE	.EQU	PPAMODE_MG014	; PPA 0: DRIVER MODE: PPAMODE_[NONE|MG014]
+PPA0BASE	.EQU	LPT0BASE	; PPA 0: BASE I/O ADDRESS OF PPI FOR PPA
+PPA1MODE	.EQU	PPAMODE_MG014	; PPA 1: DRIVER MODE: PPAMODE_[NONE|MG014]
+PPA1BASE	.EQU	LPT1BASE	; PPA 1: BASE I/O ADDRESS OF PPI FOR PPA
+;
+IMMENABLE	.EQU	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
+IMMCNT		.EQU	1		; IMM: NUMBER OF IMM DEVICES (1-2)
+IMMTRACE	.EQU	1		; IMM: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
+IMM0MODE	.EQU	IMMMODE_MG014	; IMM 0: DRIVER MODE: IMMMODE_[NONE|MG014]
+IMM0BASE	.EQU	LPT0BASE	; IMM 0: BASE I/O ADDRESS OF PPI FOR IMM
+IMM1MODE	.EQU	IMMMODE_MG014	; IMM 1: DRIVER MODE: IMMMODE_[NONE|MG014]
+IMM1BASE	.EQU	LPT1BASE	; IMM 1: BASE I/O ADDRESS OF PPI FOR IMM
+;
 PIO_4P		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
--- a/Source/HBIOS/cfg_rph.asm
+++ b/Source/HBIOS/cfg_rph.asm
@@ -236,6 +236,10 @@ PIO1BASE	.EQU	$BC		; PIO 1: REGISTERS BASE ADR
 ;
 LPTENABLE	.EQU	FALSE		; LPT: ENABLE CENTRONICS PRINTER DRIVER (LPT.ASM)
 ;
+PPAENABLE	.EQU	FALSE		; PPA: ENABLE PPA DISK DRIVER (PPA.ASM)
+;
+IMMENABLE	.EQU	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
+;
 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)
--- a/Source/HBIOS/cfg_sbc.asm
+++ b/Source/HBIOS/cfg_sbc.asm
@@ -234,11 +234,10 @@ PIO0BASE	.EQU	$B8		; PIO 0: REGISTERS BASE ADR
 PIO1BASE	.EQU	$BC		; PIO 1: REGISTERS BASE ADR
 ;
 LPTENABLE	.EQU	FALSE		; LPT: ENABLE CENTRONICS PRINTER DRIVER (LPT.ASM)
-LPTMODE		.EQU	LPTMODE_NONE	; LPT: DRIVER MODE: LPTMODE_[NONE|IBM|MG014]
-LPTCNT		.EQU	1		; LPT: NUMBER OF CHIPS TO DETECT (1-2)
-LPTTRACE	.EQU	1		; LPT: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
-LPT0BASE	.EQU	$E8		; LPT 0: REGISTERS BASE ADR
-LPT1BASE	.EQU	$EC		; LPT 1: REGISTERS BASE ADR
+;
+PPAENABLE	.EQU	FALSE		; PPA: ENABLE PPA DISK DRIVER (PPA.ASM)
+;
+IMMENABLE	.EQU	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
 ;
 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
--- a/Source/HBIOS/cfg_scz180.asm
+++ b/Source/HBIOS/cfg_scz180.asm
@@ -257,6 +257,22 @@ LPTTRACE	.EQU	1		; LPT: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
 LPT0BASE	.EQU	$18		; LPT 0: REGISTERS BASE ADR
 LPT1BASE	.EQU	$00		; LPT 1: REGISTERS BASE ADR
 ;
+PPAENABLE	.EQU	FALSE		; PPA: ENABLE PPA DISK DRIVER (PPA.ASM)
+PPACNT		.EQU	1		; PPA: NUMBER OF PPA DEVICES (1-2)
+PPATRACE	.EQU	1		; PPA: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
+PPA0MODE	.EQU	PPAMODE_MG014	; PPA 0: DRIVER MODE: PPAMODE_[NONE|MG014]
+PPA0BASE	.EQU	LPT0BASE	; PPA 0: BASE I/O ADDRESS OF PPI FOR PPA
+PPA1MODE	.EQU	PPAMODE_MG014	; PPA 1: DRIVER MODE: PPAMODE_[NONE|MG014]
+PPA1BASE	.EQU	LPT1BASE	; PPA 1: BASE I/O ADDRESS OF PPI FOR PPA
+;
+IMMENABLE	.EQU	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
+IMMCNT		.EQU	1		; IMM: NUMBER OF IMM DEVICES (1-2)
+IMMTRACE	.EQU	1		; IMM: TRACE LEVEL (0=NO,1=ERRORS,2=ALL)
+IMM0MODE	.EQU	IMMMODE_MG014	; IMM 0: DRIVER MODE: IMMMODE_[NONE|MG014]
+IMM0BASE	.EQU	LPT0BASE	; IMM 0: BASE I/O ADDRESS OF PPI FOR IMM
+IMM1MODE	.EQU	IMMMODE_MG014	; IMM 1: DRIVER MODE: IMMMODE_[NONE|MG014]
+IMM1BASE	.EQU	LPT1BASE	; IMM 1: BASE I/O ADDRESS OF PPI FOR IMM
+;
 PIO_4P		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
--- a/Source/HBIOS/cfg_z80retro.asm
+++ b/Source/HBIOS/cfg_z80retro.asm
@@ -206,6 +206,10 @@ PIOENABLE	.EQU	FALSE		; PIO: ENABLE ZILOG PIO DRIVER (PIO.ASM)
 ;
 LPTENABLE	.EQU	FALSE		; LPT: ENABLE CENTRONICS PRINTER DRIVER (LPT.ASM)
 ;
+PPAENABLE	.EQU	FALSE		; PPA: ENABLE PPA DISK DRIVER (PPA.ASM)
+;
+IMMENABLE	.EQU	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
+;
 PIO_4P		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
--- a/Source/HBIOS/cfg_zeta.asm
+++ b/Source/HBIOS/cfg_zeta.asm
@@ -177,6 +177,10 @@ PIOENABLE	.EQU	FALSE		; PIO: ENABLE ZILOG PIO DRIVER (PIO.ASM)
 ;
 LPTENABLE	.EQU	FALSE		; LPT: ENABLE CENTRONICS PRINTER DRIVER (LPT.ASM)
 ;
+PPAENABLE	.EQU	FALSE		; PPA: ENABLE PPA DISK DRIVER (PPA.ASM)
+;
+IMMENABLE	.EQU	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
+;
 PIO_4P		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
--- a/Source/HBIOS/cfg_zeta2.asm
+++ b/Source/HBIOS/cfg_zeta2.asm
@@ -188,6 +188,10 @@ PIOENABLE	.EQU	FALSE		; PIO: ENABLE ZILOG PIO DRIVER (PIO.ASM)
 ;
 LPTENABLE	.EQU	FALSE		; LPT: ENABLE CENTRONICS PRINTER DRIVER (LPT.ASM)
 ;
+PPAENABLE	.EQU	FALSE		; PPA: ENABLE PPA DISK DRIVER (PPA.ASM)
+;
+IMMENABLE	.EQU	FALSE		; IMM: ENABLE IMM DISK DRIVER (IMM.ASM)
+;
 PIO_4P		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB 4P BOARD
 PIO_ZP		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR ECB ZILOG PERIPHERALS BOARD (PIO.ASM)
 PIO_SBC		.EQU	FALSE		; PIO: ENABLE PARALLEL PORT DRIVER FOR 8255 CHIP
--- a/Source/HBIOS/hbios.asm
+++ b/Source/HBIOS/hbios.asm
@@ -1261,11 +1261,11 @@ Z280_INITZ:

 	; SET DEFAULT CPU CLOCK MULTIPLIERS (XTAL / 2)
 	;
-	; IT HAS BEEN REPORTED THAT CMR NEEDS TO BE SET PRIOR TO CCR
-	; WHEN USING AN INPUT FREQUENCY THAT IS XTAL / 2.
-	; I NEVER EXPERIENCED A PROBLEM RELATED TO ORDER, BUT JUST
+	; BILL MCMULLEN REPORTED THAT CMR NEEDS TO BE SET PRIOR TO CCR
+	; WHEN USING A CPU FREQUENCY (PHI) THAT IS XTAL * 2.
+	; HERE WE ARE SETTING CPU FREQUENCY TO XTAL / 2, BUT JUST
 	; FOR GOOD MEASURE, CMR IS SET PRIOR TO CCR BELOW.
-	; https://www.retrobrewcomputers.org/forum/index.php?t=msg&th=316&#msg_5045
+	; https://www.retrobrewcomputers.org/forum/index.php?t=msg&th=316&goto=5045&#msg_5045
 	XOR	A
 	OUT0	(Z180_CMR),A
 	OUT0	(Z180_CCR),A
@@ -3239,6 +3239,12 @@ HB_INITTBL:
 #IF (HDSKENABLE)
 	.DW	HDSK_INIT
 #ENDIF
+#IF (PPAENABLE)
+	.DW	PPA_INIT
+#ENDIF
+#IF (IMMENABLE)
+	.DW	IMM_INIT
+#ENDIF
 #IF (PRPENABLE)
 	.DW	PRP_INIT
 #ENDIF
@@ -6348,6 +6354,24 @@ SIZ_HDSK	.EQU	$ - ORG_HDSK
 		.ECHO	" bytes.\n"
 #ENDIF
 ;
+#IF (PPAENABLE)
+ORG_PPA		.EQU	$
+  #INCLUDE "ppa.asm"
+SIZ_PPA		.EQU	$ - ORG_PPA
+		.ECHO	"PPA occupies "
+		.ECHO	SIZ_PPA
+		.ECHO	" bytes.\n"
+#ENDIF
+;
+#IF (IMMENABLE)
+ORG_IMM		.EQU	$
+  #INCLUDE "imm.asm"
+SIZ_IMM		.EQU	$ - ORG_IMM
+		.ECHO	"IMM occupies "
+		.ECHO	SIZ_IMM
+		.ECHO	" bytes.\n"
+#ENDIF
+;
 #IF (TERMENABLE)
 ORG_TERM	.EQU	$
  #INCLUDE "term.asm"
@@ -6762,7 +6786,6 @@ PS_PRTDC:
 	RES	7,D			; CLEAR LBA BIT
 	LD	B,11			; 11 BIT SHIFT TO CONVERT BLOCKS --> MB
 	CALL	SRL32			; RIGHT SHIFT
-	;CALL	PRTDEC			; PRINT LOW WORD IN DECIMAL (HIGH WORD DISCARDED)
 	CALL	PRTDEC32		; PRINT DWORD IN DECIMAL
 	PRTS("MB$")			; PRINT SUFFIX
 	CALL	PC_COMMA
@@ -6777,7 +6800,6 @@ PS_PRTDC1:
 	RES	7,D			; CLEAR LBA BIT
 	LD	B,1			; 11 BIT SHIFT TO CONVERT BLOCKS --> MB
 	CALL	SRL32			; RIGHT SHIFT
-	;CALL	PRTDEC			; PRINT LOW WORD IN DECIMAL (HIGH WORD DISCARDED)
 	CALL	PRTDEC32		; PRINT DWORD IN DECIMAL
 	PRTS("KB$")			; PRINT SUFFIX
 	CALL	PC_COMMA
@@ -7134,6 +7156,8 @@ PS_DDSD		.TEXT	"SD$"
 PS_DDPRPSD	.TEXT	"PRPSD$"
 PS_DDPPPSD	.TEXT	"PPPSD$"
 PS_DDHDSK	.TEXT	"HDSK$"
+PS_DDPPA	.TEXT	"PPA$"
+PS_DDIMM	.TEXT	"IMM$"
 ;
 ; DISK TYPE STRINGS
 ;
--- a/Source/HBIOS/hbios.inc
+++ b/Source/HBIOS/hbios.inc
@@ -321,6 +321,8 @@ DIODEV_SD	.EQU	$60
 DIODEV_PRPSD	.EQU	$70
 DIODEV_PPPSD	.EQU	$80
 DIODEV_HDSK	.EQU	$90
+DIODEV_PPA	.EQU	$A0
+DIODEV_IMM	.EQU	$B0
 ;
 ; RTC DEVICE IDS
 ;
--- a/Source/HBIOS/imm.asm
+++ b/Source/HBIOS/imm.asm
--- a/Source/HBIOS/lpt.asm
+++ b/Source/HBIOS/lpt.asm
@@ -372,7 +372,7 @@ LPT_PRTCFG:
 	CALL	PRTHEXBYTE		; PRINT BASE PORT

 	; PRINT THE LPT TYPE
-	CALL	PC_SPACE		; FORMATTING
+	PRTS(": MODE=$")		; FORMATTING
 	LD	A,(IY+1)		; GET LPT TYPE BYTE
 	RLCA				; MAKE IT A WORD OFFSET
 	LD	HL,LPT_TYPE_MAP		; POINT HL TO TYPE MAP TABLE
--- a/Source/HBIOS/ppa.asm
+++ b/Source/HBIOS/ppa.asm
@@ -0,0 +1,892 @@
+;
+;=============================================================================
+;   PPA DISK DRIVER
+;=============================================================================
+;
+; PARALLEL PORT INTERFACE FOR SCSI DISK DEVICES USING A PARALLEL PORT
+; ADAPTER.  PRIMARILY TARGETS PARALLEL PORT IOMEGA ZIP DRIVES.
+;
+; CURRENTLY CODED SPECIFICALLY FOR RCBUS MG014 PARALLEL PORT HARDWARE.
+; INTENDED TO CO-EXIST WITH LPT DRIVER.
+;
+; CREATED BY WAYNE WARTHEN FOR ROMWBW HBIOS.
+; MUCH OF THE CODE IS DERIVED FROM FUZIX (ALAN COX).
+;
+; 5/23/2023 WBW - INITIAL RELEASE
+; 5/26/3023 WBW - CLEAN UP, LED ACTIVITY
+;
+;=============================================================================
+;
+;  MG014 STYLE INTERFACE (USED BY RCBUS MG014 MODULE):
+;
+;  PORT 0 (INPUT/OUTPUT):
+;
+;	D7	D6	D5	D4	D3	D2	D1	D0
+;     +-------+-------+-------+-------+-------+-------+-------+-------+
+;     | PD7   | PD6   | PD5   | PD4   | PD3   | PD2   | PD1   | PD0   |
+;     +-------+-------+-------+-------+-------+-------+-------+-------+
+;
+;  PORT 1 (INPUT):
+;
+;	D7	D6	D5	D4	D3	D2	D1	D0
+;     +-------+-------+-------+-------+-------+-------+-------+-------+
+;     |	      |	      |	      | /ERR  | SEL   | POUT  | BUSY  | /ACK  |
+;     +-------+-------+-------+-------+-------+-------+-------+-------+
+;
+;  PORT 2 (INPUT/OUTPUT):
+;
+;	D7	D6	D5	D4	D3	D2	D1	D0
+;     +-------+-------+-------+-------+-------+-------+-------+-------+
+;     | LED   |	      |	      |	      | /SEL  | /RES  | /LF   | /STB  |
+;     +-------+-------+-------+-------+-------+-------+-------+-------+
+;
+;=============================================================================
+;
+; TODO:
+;
+; - CLEAN UP WAIT LOOP STUFF
+;
+; - OPTIMIZE READ/WRITE LOOPS
+;
+; NOTES:
+;
+; - THIS DRIVER IS FOR THE ZIP DRIVE PPA INTERFACE.  IT WILL SIMPLY
+;   FAIL TO EVEN RECOGNIZE A ZIP DRIVE WITH THE OLDER PPA INTERFACE.
+;   THERE DOES NOT SEEM TO BE A WAY TO VISUALLY DETERMINE IF A ZIP
+;   DRIVE IS PPA OR PPA.  SIGH.
+;
+; - THERE ARE SOME HARD CODED TIMEOUT LOOPS IN THE CODE.  THEY ARE
+;   WORKING OK ON A 7 MHZ Z80.  THEY ARE LIKELY TO NEED TWEAKING ON
+;   FASTER CPUS.
+;
+; - THIS DRIVER OPERATES PURELY IN NIBBLE MODE.  I SUSPECT IT IS
+;   POSSIBLE TO USE FULL BYTE MODE (PS2 STYLE), BUT I HAVE NOT
+;   ATTEMPTED IT.
+;
+; - RELATIVE TO ABOVE, THIS BEAST IS SLOW.  IN ADDITION TO THE
+;   NIBBLE MODE READS, THE MG014 ASSIGNS SIGNALS DIFFERENTLY THAN
+;   THE STANDARD IBM PARALLEL PORT WHICH NECESSITATES A BUNCH OF EXTRA
+;   BIT FIDDLING ON EVERY READ.
+;
+; - SOME OF THE DATA TRANSFERS HAVE NO BUFFER OVERRUN CHECKS.  IT IS
+;   ASSUMED SCSI DEVICES WILL SEND/REQUEST THE EXPECTED NUMBER OF BYTES.
+;
+; PPA PORT OFFSETS
+;
+PPA_IODATA	.EQU	0		; PORT A, DATA, OUT
+PPA_IOSTAT	.EQU	1		; PORT B, STATUS, IN
+PPA_IOCTRL	.EQU	2		; PORT C, CTRL, OUT
+PPA_IOSETUP	.EQU	3		; PPI SETUP
+;
+; SCSI UNIT IDS
+;
+PPA_SELF	.EQU	7
+PPA_TGT		.EQU	6
+;
+; PPA DEVICE STATUS
+;
+PPA_STOK	.EQU	0
+PPA_STINVUNIT	.EQU	-1
+PPA_STNOMEDIA	.EQU	-2
+PPA_STCMDERR	.EQU	-3
+PPA_STIOERR	.EQU	-4
+PPA_STTO	.EQU	-5
+PPA_STNOTSUP	.EQU	-6
+;
+; PPA DEVICE CONFIGURATION
+;
+PPA_CFGSIZ	.EQU	12		; SIZE OF CFG TBL ENTRIES
+;
+; PER DEVICE DATA OFFSETS IN CONFIG TABLE ENTRIES
+;
+PPA_DEV		.EQU	0		; OFFSET OF DEVICE NUMBER (BYTE)
+PPA_MODE	.EQU	1		; OPERATION MODE: PPA MODE (BYTE)
+PPA_STAT	.EQU	2		; LAST STATUS (BYTE)
+PPA_IOBASE	.EQU	3		; IO BASE ADDRESS (BYTE)
+PPA_MEDCAP	.EQU	4		; MEDIA CAPACITY (DWORD)
+PPA_LBA		.EQU	8		; OFFSET OF LBA (DWORD)
+;
+;=============================================================================
+; INITIALIZATION ENTRY POINT
+;=============================================================================
+;
+PPA_INIT:
+	LD	IY,PPA_CFG		; POINT TO START OF CONFIG TABLE
+;
+PPA_INIT1:
+	LD	A,(IY)			; LOAD FIRST BYTE TO CHECK FOR END
+	CP	$FF			; CHECK FOR END OF TABLE VALUE
+	JR	NZ,PPA_INIT2		; IF NOT END OF TABLE, CONTINUE
+	XOR	A			; SIGNAL SUCCESS
+	RET				; AND RETURN
+;
+PPA_INIT2:
+	CALL	NEWLINE			; FORMATTING
+	PRTS("PPA:$")			; DRIVER LABEL
+;
+	PRTS(" IO=0x$")			; LABEL FOR IO ADDRESS
+	LD	A,(IY+PPA_IOBASE)	; GET IO BASE ADDRES
+	CALL	PRTHEXBYTE		; DISPLAY IT
+;
+	PRTS(" MODE=$")			; LABEL FOR MODE
+	LD	A,(IY+PPA_MODE)		; GET MODE BITS
+	LD	DE,PPA_STR_MODE_NONE	; MODE LABEL
+	CP	PPAMODE_NONE		; TEST FOR MODE
+	JR	Z,PPA_INIT3		; IF SO, DISPLAY IT
+	LD	DE,PPA_STR_MODE_MG014	; MODE LABEL
+	CP	PPAMODE_MG014		; TEST FOR MODE
+	JR	Z,PPA_INIT3		; IF SO, DISPLAY IT
+	LD	DE,PPA_STR_MODE_UNK	; MODE LABEL
+PPA_INIT3:
+	CALL	WRITESTR		; DISPLAY MODE
+;
+	; CHECK FOR HARDWARE PRESENCE
+	CALL	PPA_DETECT		; PROBE FOR INTERFACE
+	JR	Z,PPA_INIT4		; IF FOUND, CONTINUE
+	CALL	PC_SPACE		; FORMATTING
+	LD	DE,PPA_STR_NOHW		; NO PPA MESSAGE
+	CALL	WRITESTR		; DISPLAY IT
+	JR	PPA_INIT6		; SKIP CFG ENTRY
+;
+PPA_INIT4:
+	; UPDATE DRIVER RELATIVE UNIT NUMBER IN CONFIG TABLE
+	LD	A,(PPA_DEVNUM)		; GET NEXT UNIT NUM TO ASSIGN
+	LD	(IY+PPA_DEV),A		; UPDATE IT
+	INC	A			; BUMP TO NEXT UNIT NUM TO ASSIGN
+	LD	(PPA_DEVNUM),A		; SAVE IT
+;
+	; ADD UNIT TO GLOBAL DISK UNIT TABLE
+	LD	BC,PPA_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	PPA_RESET		; RESET/INIT THE INTERFACE
+;
+	; START PRINTING DEVICE INFO
+	CALL	PPA_PRTPREFIX		; PRINT DEVICE PREFIX
+;
+	; CHECK FOR BAD STATUS
+	LD	A,(IY+PPA_STAT)		; GET STATUS
+	OR	A			; SET FLAGS
+	JP	Z,PPA_INIT5		; CONTINUE
+	CALL	PC_SPACE		; FORMATTING
+	CALL	PPA_PRTSTATSTR		; PRINT STATUS STRING
+	JR	PPA_INIT6		; LOOP TILL DONE
+;
+PPA_INIT5:
+	; PRINT STORAGE CAPACITY (BLOCK COUNT)
+	PRTS(" BLOCKS=0x$")		; PRINT FIELD LABEL
+	LD	A,PPA_MEDCAP		; OFFSET TO CAPACITY FIELD
+	CALL	LDHLIYA			; HL := IY + A, REG A TRASHED
+	CALL	LD32			; GET THE CAPACITY VALUE
+	CALL	PRTHEX32		; PRINT HEX VALUE
+;
+	; PRINT STORAGE SIZE IN MB
+	PRTS(" SIZE=$")			; 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
+;
+PPA_INIT6:
+	LD	DE,PPA_CFGSIZ		; SIZE OF CFG TABLE ENTRY
+	ADD	IY,DE			; BUMP POINTER
+	JP	PPA_INIT1		; AND LOOP
+;
+;----------------------------------------------------------------------
+; PROBE FOR PPA HARDWARE
+;----------------------------------------------------------------------
+;
+; ON RETURN, ZF SET INDICATES HARDWARE FOUND
+;
+PPA_DETECT:
+	; INITIALIZE 8255
+	LD	A,(IY+PPA_IOBASE)	; BASE PORT
+	ADD	A,PPA_IOSETUP		; BUMP TO SETUP PORT
+	LD	C,A			; MOVE TO C FOR I/O
+	LD	A,$82			; CONFIG A OUT, B IN, C OUT
+	OUT	(C),A			; DO IT
+	CALL	DELAY			; BRIEF DELAY FOR GOOD MEASURE
+;
+	LD	A,$AA
+	CALL	PPA_WRITEDATA
+	CALL	PPA_DISCONNECT
+	CALL	PPA_CONNECT
+	LD	A,$06
+	CALL	PPA_WRITECTRL
+	CALL	PPA_READSTATUS
+;
+	CALL	PC_SPACE
+	CALL	PRTHEXBYTE
+;
+	AND	$F0
+	CP	$F0
+	JR	NZ,PPA_DETECT_FAIL
+	LD	A,$04
+	CALL	PPA_WRITECTRL
+	CALL	PPA_READSTATUS
+;
+	CALL	PC_SPACE
+	CALL	PRTHEXBYTE
+;
+	AND	$F0
+	CP	$80
+	JR	NZ,PPA_DETECT_FAIL
+	LD	A,$AA
+	CALL	PPA_WRITEDATA
+	LD	A,$0C
+	CALL	PPA_WRITECTRL
+	CALL	PPA_CONNECT
+	LD	A,$40
+	CALL	PPA_WRITEDATA
+	LD	A,$08
+	CALL	PPA_WRITECTRL
+	LD	A,$0C
+	CALL	PPA_WRITECTRL
+	CALL	PPA_DISCONNECT
+;
+	XOR	A			; SIGNAL SUCCESS
+	RET				; AND RETURN
+;
+PPA_DETECT_FAIL:
+	OR	$FF			; SIGNAL FAILURE
+	RET	NZ
+
+;
+;=============================================================================
+; DRIVER FUNCTION TABLE
+;=============================================================================
+;
+PPA_FNTBL:
+	.DW	PPA_STATUS
+	.DW	PPA_RESET
+	.DW	PPA_SEEK
+	.DW	PPA_READ
+	.DW	PPA_WRITE
+	.DW	PPA_VERIFY
+	.DW	PPA_FORMAT
+	.DW	PPA_DEVICE
+	.DW	PPA_MEDIA
+	.DW	PPA_DEFMED
+	.DW	PPA_CAP
+	.DW	PPA_GEOM
+#IF (($ - PPA_FNTBL) != (DIO_FNCNT * 2))
+	.ECHO	"*** INVALID PPA FUNCTION TABLE ***\n"
+#ENDIF
+;
+PPA_VERIFY:
+PPA_FORMAT:
+PPA_DEFMED:
+	SYSCHKERR(ERR_NOTIMPL)		; NOT IMPLEMENTED
+	RET
+;
+;
+;
+PPA_READ:
+	CALL	HB_DSKREAD		; HOOK DISK READ CONTROLLER
+	LD	A,SCSI_CMD_READ		; SETUP SCSI READ
+	LD	(PPA_CMD_RW),A		; AND SAVE IT IN SCSI CMD
+	JP	PPA_IO			; DO THE I/O
+;
+;
+;
+PPA_WRITE:
+	CALL	HB_DSKREAD		; HOOK DISK WRITE CONTROLLER
+	LD	A,SCSI_CMD_WRITE	; SETUP SCSI WRITE
+	LD	(PPA_CMD_RW),A		; AND SAVE IT IN SCSI CMD
+	JP	PPA_IO			; DO THE I/O
+;
+;
+;
+PPA_IO:
+	LD	(PPA_DSKBUF),HL		; SAVE DISK BUFFER ADDRESS
+	CALL	PPA_CHKERR		; CHECK FOR ERR STATUS AND RESET IF SO
+	JR	NZ,PPA_IO3		; BAIL OUT ON ERROR
+;
+	; SETUP LBA
+	; 3 BYTES, LITTLE ENDIAN -> BIG ENDIAN
+	LD	HL,PPA_CMD_RW+1		; START OF LBA FIELD IN CDB (MSB)
+	LD	A,(IY+PPA_LBA+2)	; THIRD BYTE OF LBA FIELD IN CFG (MSB)
+	LD	(HL),A
+	INC	HL
+	LD	A,(IY+PPA_LBA+1)
+	LD	(HL),A
+	INC	HL
+	LD	A,(IY+PPA_LBA+0)
+	LD	(HL),A
+	INC	HL
+;
+	; DO SCSI IO
+	LD	DE,(PPA_DSKBUF)		; DISK BUFFER TO DE
+	LD	BC,512			; ONE SECTOR, 512 BYTES
+	LD	HL,PPA_CMD_RW		; POINT TO READ/WRITE CMD TEMPLATE
+	CALL	PPA_RUNCMD		; RUN THE SCSI ENGINE
+	CALL	Z,PPA_CHKCMD		; IF EXIT OK, CHECK SCSI RESULTS
+	JR	NZ,PPA_IO2		; IF ERROR, SKIP INCREMENT
+	; INCREMENT LBA
+	LD	A,PPA_LBA		; LBA OFFSET
+	CALL	LDHLIYA			; HL := IY + A, REG A TRASHED
+	CALL	INC32HL			; INCREMENT THE VALUE
+	; INCREMENT DMA
+	LD	HL,IDE_DSKBUF+1		; POINT TO MSB OF BUFFER ADR
+	INC	(HL)			; BUMP DMA BY
+	INC	(HL)			; ... 512 BYTES
+	XOR	A			; SIGNAL SUCCESS
+;
+PPA_IO2:
+PPA_IO3:
+	LD	HL,(PPA_DSKBUF)		; CURRENT DMA TO HL
+	OR	A			; SET FLAGS BASED ON RETURN CODE
+	RET	Z			; RETURN IF SUCCESS
+	LD	A,ERR_IO		; SIGNAL IO ERROR
+	OR	A			; SET FLAGS
+	RET				; AND DONE
+;
+;
+;
+PPA_STATUS:
+	; RETURN UNIT STATUS
+	LD	A,(IY+PPA_STAT)		; GET STATUS OF SELECTED DEVICE
+	OR	A			; SET FLAGS
+	RET				; AND RETURN
+;
+;
+;
+PPA_RESET:
+	JP	PPA_INITDEV		; JUST (RE)INIT DEVICE
+;
+;
+;
+PPA_DEVICE:
+	LD	D,DIODEV_PPA		; D := DEVICE TYPE
+	LD	E,(IY+PPA_DEV)		; E := PHYSICAL DEVICE NUMBER
+	LD	C,%01000000		; C := REMOVABLE HARD DISK
+	LD	H,(IY+PPA_MODE)		; H := MODE
+	LD	L,(IY+PPA_IOBASE)	; L := BASE I/O ADDRESS
+	XOR	A			; SIGNAL SUCCESS
+	RET
+;
+; PPA_GETMED
+;
+PPA_MEDIA:
+	LD	A,E			; GET FLAGS
+	OR	A			; SET FLAGS
+	JR	Z,PPA_MEDIA1		; JUST REPORT CURRENT STATUS AND MEDIA
+;
+	CALL	PPA_RESET		; RESET INCLUDES MEDIA CHECK
+;
+PPA_MEDIA1:
+	LD	A,(IY+PPA_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
+;
+;
+;
+PPA_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+PPA_LBA+0),L	; SAVE NEW LBA
+	LD	(IY+PPA_LBA+1),H	; ...
+	LD	(IY+PPA_LBA+2),E	; ...
+	LD	(IY+PPA_LBA+3),D	; ...
+	XOR	A			; SIGNAL SUCCESS
+	RET				; AND RETURN
+;
+;
+;
+PPA_CAP:
+	LD	A,(IY+PPA_STAT)		; GET STATUS
+	PUSH	AF			; SAVE IT
+	LD	A,PPA_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
+;
+;
+;
+PPA_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	PPA_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 PPA_CAP STATUS
+;
+;=============================================================================
+; FUNCTION SUPPORT ROUTINES
+;=============================================================================
+;
+;
+;
+PPA_DELAY:
+	PUSH	AF
+	CALL	DELAY
+	CALL	DELAY
+	CALL	DELAY
+	CALL	DELAY
+	POP	AF
+	RET
+;
+;
+;
+PPA_WAITDONE:
+	LD	HL,0			; TIMEOUT COUNTER
+PPA_WAITDONE1:
+	CALL	PPA_READSTATUS
+	AND	$F0
+	BIT	7,A
+	RET	NZ
+	DEC	HL
+	LD	A,H
+	OR	L
+	JP	Z,IMM_CMD_TIMEOUT	; TIMEOUT
+	JR	PPA_WAITDONE1
+;
+; OUTPUT BYTE IN A TO THE DATA PORT
+;
+PPA_WRITEDATA:
+	LD	C,(IY+PPA_IOBASE)	; DATA PORT IS AT IOBASE
+	OUT	(C),A			; WRITE THE BYTE
+	;CALL	DELAY			; IS THIS NEEDED???
+	RET				; DONE
+;
+;
+;
+PPA_WRITECTRL:
+	; IBM PC INVERTS ALL BUT C2 ON THE BUS, MG014 DOES NOT.
+	; BELOW TRANSLATES FROM IBM -> MG014.	IT ALSO INVERTS THE
+	; MG014 LED SIMPLY TO MAKE IT EASY TO KEEP LED ON DURING
+	; ALL ACTIVITY.
+	XOR	$0B | $80		; HIGH BIT IS MG014 LED
+	LD	C,(IY+PPA_IOBASE)	; GET BASE IO ADDRESS
+	INC	C			; BUMP TO CONTROL PORT
+	INC	C
+	OUT	(C),A			; WRITE TO CONTROL PORT
+	;CALL	DELAY			; IS THIS NEEDED?
+	RET				; DONE
+;
+; READ THE PARALLEL PORT INPUT LINES (STATUS) AND MAP SIGNALS FROM
+; MG014 TO IBM STANDARD.  NOTE POLARITY CHANGE REQUIRED FOR BUSY.
+;
+; 	MG014		IBM PC
+;	--------	--------
+;	0: /ACK		6: /ACK
+;	1: BUSY		7: /BUSY
+;	2: POUT		5: POUT
+;	3: SEL		4: SEL
+;	4: /ERR		3: /ERR
+;
+PPA_READSTATUS:
+	LD	C,(IY+PPA_IOBASE)	; IOBASE TO C
+	INC	C			; BUMP TO STATUS PORT
+	IN	A,(C)			; READ IT
+	LD	C,0			; INIT RESULT
+;
+	; SHUFFLE BITS
+	BIT	0,A			; 0: /ACK
+	JR	Z,PPA_READSTATUS1
+	SET	6,C			; 6: /ACK
+;
+PPA_READSTATUS1:
+;
+	BIT	1,A			; 1: BUSY
+	JR	NZ,PPA_READSTATUS2	; POLARITY CHANGE!
+	SET	7,C			; 7: /BUSY
+;
+PPA_READSTATUS2:
+;
+	BIT	2,A			; 2: POUT
+	JR	Z,PPA_READSTATUS3
+	SET	5,C			; 5: POUT
+;
+PPA_READSTATUS3:
+;
+	BIT	3,A			; 3: SEL
+	JR	Z,PPA_READSTATUS4
+	SET	4,C			; 4: SEL
+;
+PPA_READSTATUS4:
+;
+	BIT	4,A			; 4: /ERR
+	JR	Z,PPA_READSTATUS5
+	SET	3,C			; 3: /ERR
+;
+PPA_READSTATUS5:
+	LD	A,C			; RESULT TO A
+	RET
+;
+;
+;
+PPA_DPULSE:
+	CALL	PPA_WRITEDATA
+	LD	A,$0C
+	CALL	PPA_WRITECTRL
+	LD	A,$0E
+	CALL	PPA_WRITECTRL
+	LD	A,$0C			;?
+	CALL	PPA_WRITECTRL		;?
+	LD	A,$04
+	CALL	PPA_WRITECTRL
+	LD	A,$0C
+	CALL	PPA_WRITECTRL
+	RET
+;
+;
+;
+PPA_CPULSE:
+	CALL	PPA_WRITEDATA
+	LD	A,$04
+	CALL	PPA_WRITECTRL
+	LD	A,$06
+	CALL	PPA_WRITECTRL
+	LD	A,$04
+	CALL	PPA_WRITECTRL
+	LD	A,$0C
+	CALL	PPA_WRITECTRL
+	RET
+;
+;
+;
+PPA_CONNECT:
+	LD	A,$00
+	CALL	PPA_CPULSE
+	LD	A,$3C
+	CALL	PPA_CPULSE
+	LD	A,$20
+	CALL	PPA_CPULSE
+	LD	A,$8F
+	CALL	PPA_CPULSE
+	RET
+;
+;
+;
+PPA_DISCONNECT:
+	LD	A,$00
+	CALL	PPA_DPULSE
+	LD	A,$3C
+	CALL	PPA_DPULSE
+	LD	A,$20
+	CALL	PPA_DPULSE
+	LD	A,$0F
+	CALL	PPA_DPULSE
+	RET
+;
+; SCSI SELECT PROCESS
+;
+;
+PPA_SELECT:
+	LD	A,1 << PPA_TGT
+	CALL	PPA_WRITEDATA
+	LD	A,$0E
+	CALL	PPA_WRITECTRL
+	LD	A,$0C
+	CALL	PPA_WRITECTRL
+	LD	A,1 << PPA_SELF
+	CALL	PPA_WRITEDATA
+	LD	A,$08
+	CALL	PPA_WRITECTRL
+;
+	LD	HL,0			; TIMEOUT COUNTER
+;
+PPA_SELECT1:
+	CALL	PPA_READSTATUS
+	OR	$F0
+	RET	NZ
+	DEC	HL
+	LD	A,H
+	OR	L
+	RET	Z			; TIMEOUT
+	JR	PPA_SELECT1
+;
+; SEND SCSI CMD BYTE STRING.  AT ENTRY, HL POINTS TO START OF
+; COMMAND BYTES.  THE LENGTH OF THE COMMAND STRING MUST PRECEED
+; THE COMMAND BYTES (HL - 1).
+;
+; NOTE THAT DATA IS SENT AS BYTE PAIRS!  EACH LOOP SENDS 2 BYTES.
+; DATA OUTPOUT IS BURSTED (NO CHECK FOR BUSY).  SEEMS TO WORK FINE.
+;
+PPA_SENDCMD:
+	JP	PPA_ERR			; NOW DO STANDARD ERR PROCESSING
+;
+; THIS IS THE MAIN SCSI ENGINE.  BASICALLY, IT SELECTS THE DEVICE
+; ON THE BUS, SENDS THE COMMAND, THEN PROCESSES THE RESULT.
+;
+; HL: COMMAND BUFFER
+; DE: TRANSFER BUFFER
+; BC: TRANSFER LENGTH (0=VARIABLE)
+;
+PPA_RUNCMD:
+	JP	PPA_ERR			; NOW DO STANDARD ERR PROCESSING
+;
+; ERRORS SHOULD GENERALLY NOT CAUSE SCSI PROCESSING TO FAIL.  IF A
+; DEVICE ERROR (I.E., READ ERROR) OCCURS, THEN THE SCSI PROTOCOL WILL
+; PROVIDE ERROR INFORMATION.  THE STATUS RESULT OF THE SCSI COMMAND
+; WILL INDICATE IF AN ERROR OCCURRED.  ADDITIONALLY, IF THE ERROR IS
+; A CHECK CONDITION ERROR, THEN IT IS MANDATORY TO ISSUE A SENSE
+; REQUEST SCSI COMMAND TO CLEAR THE ERROR AND RETRIEVE DETAILED ERROR
+; INFO.
+;
+PPA_CHKCMD:
+	; SCSI COMMAND COMPLETED, CHECK SCSI CMD STATUS
+	LD	A,(PPA_CMDSTAT)		; GET STATUS BYTE
+	OR	A			; SET FLAGS
+	RET	Z			; IF ZERO, ALL GOOD, DONE
+;
+	; DO WE HAVE A CHECK CONDITION?
+	CP	2			; CHECK CONDITION RESULT?
+	JR	Z,PPA_CHKCMD1		; IF SO, REQUEST SENSE
+	JP	PPA_IOERR		; ELSE, GENERAL I/O ERROR
+;
+PPA_CHKCMD1:
+	; USE REQUEST SENSE CMD TO GET ERROR DETAILS
+	LD	DE,HB_WRKBUF		; PUT DATA IN WORK BUF
+	LD	BC,0			; VARIABLE LENGTH REQUEST
+	LD	HL,PPA_CMD_SENSE	; REQUEST SENSE CMD
+	CALL	PPA_RUNCMD		; DO IT
+	JP	NZ,PPA_IOERR		; BAIL IF ERROR IN CMD
+;
+	; REQ SENSE CMD COMPLETED
+#IF (PPATRACE >= 3)
+	LD	A,16
+	LD	DE,HB_WRKBUF
+	CALL	Z,PRTHEXBUF
+#ENDIF
+;
+	; CHECK SCSI CMD STATUS
+	LD	A,(PPA_CMDSTAT)		; GET STATUS BYTE
+	OR	A			; SET FLAGS
+	JP	NZ,PPA_IOERR		; IF FAILED, GENERAL I/O ERROR
+;
+	; RETURN RESULT BASED ON REQ SENSE DATA
+	; TODO: WE NEED TO CHECK THE SENSE KEY FIRST!!!
+	LD	A,(HB_WRKBUF+12)	; GET ADDITIONAL SENSE CODE
+	CP	$3A			; NO MEDIA?
+	JP	Z,PPA_NOMEDIA		; IF SO, RETURN NO MEDIA ERR
+	JP	PPA_IOERR		; ELSE GENERAL I/O ERR
+;
+; CHECK CURRENT DEVICE FOR ERROR STATUS AND ATTEMPT TO RECOVER
+; VIA RESET IF DEVICE IS IN ERROR.
+;
+PPA_CHKERR:
+	LD	A,(IY+PPA_STAT)		; GET STATUS
+	OR	A			; SET FLAGS
+	CALL	NZ,PPA_RESET		; IF ERROR STATUS, RESET BUS
+	RET
+;
+; (RE)INITIALIZE DEVICE
+;
+PPA_INITDEV:
+	; INITIALIZE 8255
+	LD	A,(IY+PPA_IOBASE)	; BASE PORT
+	ADD	A,PPA_IOSETUP		; BUMP TO SETUP PORT
+	LD	C,A			; MOVE TO C FOR I/O
+	LD	A,$82			; CONFIG A OUT, B IN, C OUT
+	OUT	(C),A			; DO IT
+	CALL	DELAY			; SHORT DELAY FOR BUS SETTLE
+;
+;=============================================================================
+; ERROR HANDLING AND DIAGNOSTICS
+;=============================================================================
+;
+; ERROR HANDLERS
+;
+PPA_INVUNIT:
+	LD	A,PPA_STINVUNIT
+	JR	PPA_ERR2		; SPECIAL CASE FOR INVALID UNIT
+;
+PPA_NOMEDIA:
+	LD	A,PPA_STNOMEDIA
+	JR	PPA_ERR
+;
+PPA_CMDERR:
+	LD	A,PPA_STCMDERR
+	JR	PPA_ERR
+;
+PPA_IOERR:
+	LD	A,PPA_STIOERR
+	JR	PPA_ERR
+;
+PPA_TO:
+	LD	A,PPA_STTO
+	JR	PPA_ERR
+;
+PPA_NOTSUP:
+	LD	A,PPA_STNOTSUP
+	JR	PPA_ERR
+;
+PPA_ERR:
+	LD	(IY+PPA_STAT),A		; SAVE NEW STATUS
+;
+PPA_ERR2:
+#IF (PPATRACE >= 2)
+	CALL	PPA_PRTSTAT
+#ENDIF
+	OR	A			; SET FLAGS
+	RET
+;
+;
+;
+PPA_PRTERR:
+	RET	Z			; DONE IF NO ERRORS
+	; FALL THRU TO PPA_PRTSTAT
+;
+; PRINT FULL DEVICE STATUS LINE
+;
+PPA_PRTSTAT:
+	PUSH	AF
+	PUSH	DE
+	PUSH	HL
+	LD	A,(IY+PPA_STAT)
+	CP	PPA_STINVUNIT
+	JR	Z,PPA_PRTSTAT2		; INVALID UNIT IS SPECIAL CASE
+	CALL	PPA_PRTPREFIX		; PRINT UNIT PREFIX
+	JR	PPA_PRTSTAT3
+PPA_PRTSTAT2:
+	CALL	NEWLINE
+	PRTS("PPA:$")			; NO UNIT NUM IN PREFIX FOR INVALID UNIT
+PPA_PRTSTAT3:
+	CALL	PC_SPACE		; FORMATTING
+	CALL	PPA_PRTSTATSTR
+	POP	HL
+	POP	DE
+	POP	AF
+	RET
+;
+; PRINT STATUS STRING
+;
+PPA_PRTSTATSTR:
+	PUSH	AF
+	PUSH	DE
+	LD	A,(IY+PPA_STAT)
+	OR	A
+	LD	DE,PPA_STR_STOK
+	JR	Z,PPA_PRTSTATSTR1
+	INC	A
+	LD	DE,PPA_STR_STINVUNIT
+	JR	Z,PPA_PRTSTATSTR1
+	INC	A
+	LD	DE,PPA_STR_STNOMEDIA
+	JR	Z,PPA_PRTSTATSTR1
+	INC	A
+	LD	DE,PPA_STR_STCMDERR
+	JR	Z,PPA_PRTSTATSTR1
+	INC	A
+	LD	DE,PPA_STR_STIOERR
+	JR	Z,PPA_PRTSTATSTR1
+	INC	A
+	LD	DE,PPA_STR_STTO
+	JR	Z,PPA_PRTSTATSTR1
+	INC	A
+	LD	DE,PPA_STR_STNOTSUP
+	JR	Z,PPA_PRTSTATSTR1
+	LD	DE,PPA_STR_STUNK
+PPA_PRTSTATSTR1:
+	CALL	WRITESTR
+	POP	DE
+	POP	AF
+	RET
+;
+; PRINT DIAGNONSTIC PREFIX
+;
+PPA_PRTPREFIX:
+	PUSH	AF
+	CALL	NEWLINE
+	PRTS("PPA$")
+	LD	A,(IY+PPA_DEV)		; GET CURRENT DEVICE NUM
+	CP	$FE			; NOT YET ASSIGNED?
+	JR	Z,PPA_PRTPREFIX1	; SKIP DEV NUM IF SO
+	CALL	PRTDECB
+PPA_PRTPREFIX1:
+	CALL	PC_COLON
+	POP	AF
+	RET
+;
+;=============================================================================
+; STRING DATA
+;=============================================================================
+;
+PPA_STR_STOK		.TEXT	"OK$"
+PPA_STR_STINVUNIT	.TEXT	"INVALID UNIT$"
+PPA_STR_STNOMEDIA	.TEXT	"NO MEDIA$"
+PPA_STR_STCMDERR	.TEXT	"COMMAND ERROR$"
+PPA_STR_STIOERR		.TEXT	"IO ERROR$"
+PPA_STR_STTO		.TEXT	"TIMEOUT$"
+PPA_STR_STNOTSUP	.TEXT	"NOT SUPPORTED$"
+PPA_STR_STUNK		.TEXT	"UNKNOWN ERROR$"
+;
+PPA_STR_NOHW		.TEXT	"NOT PRESENT$"
+;
+PPA_STR_MODE_NONE	.TEXT	"NONE$"
+PPA_STR_MODE_MG014	.TEXT	"MG014$"
+PPA_STR_MODE_UNK	.TEXT	"???$"
+;
+;=============================================================================
+; DATA STORAGE
+;=============================================================================
+;
+PPA_DEVNUM	.DB	0		; TEMP DEVICE NUM USED DURING INIT
+PPA_CMDSTK	.DW	0		; STACK PTR FOR CMD ABORTING
+PPA_DSKBUF	.DW	0		; WORKING DISK BUFFER POINTER
+PPA_XFRLEN	.DW	0		; WORKING TRANSFER LENGTH
+PPA_CMDSTAT	.DB	0, 0		; CMD RESULT STATUS
+;
+PPA_TYPE_MAP:
+		.DW	PPA_STR_NONE
+		.DW	PPA_STR_MG014
+;
+PPA_STR_NONE	.DB	"<NOT PRESENT>$"
+PPA_STR_MG014	.DB	"MG014$"
+;
+; SCSI COMMAND TEMPLATES (LENGTH PREFIXED)
+;
+		.DB	6
+PPA_CMD_RW	.DB	$00, $00, $00, $00, $01, $00	; READ/WRITE SECTOR
+		.DB	6
+PPA_CMD_SENSE	.DB	$03, $00, $00, $00, $FF, $00	; REQUEST SENSE DATA
+		.DB	10
+PPA_CMD_RDCAP	.DB	$25, $00, $00, $00, $00, $00, $00, $00, $00, $00 ; READ CAPACITY
+;
+; PPA DEVICE CONFIGURATION TABLE
+;
+PPA_CFG:
+;
+#IF (PPACNT >= 1)
+;
+PPA0_CFG:	; DEVICE 0
+	.DB	0			; DRIVER DEVICE NUMBER (FILLED DYNAMICALLY)
+	.DB	PPA0MODE		; DRIVER DEVICE MODE
+	.DB	0			; DEVICE STATUS
+	.DB	PPA0BASE		; IO BASE ADDRESS
+	.DW	0,0			; DEVICE CAPACITY
+	.DW	0,0			; CURRENT LBA
+#ENDIF
+;
+#IF (PPACNT >= 2)
+;
+PPA1_CFG:	; DEVICE 1
+	.DB	0			; DRIVER DEVICE NUMBER (FILLED DYNAMICALLY)
+	.DB	PPA1MODE		; DRIVER DEVICE MODE
+	.DB	0			; DEVICE STATUS
+	.DB	PPA1BASE		; IO BASE ADDRESS
+	.DW	0,0			; DEVICE CAPACITY
+	.DW	0,0			; CURRENT LBA
+#ENDIF
+;
+#IF ($ - PPA_CFG) != (PPACNT * PPA_CFGSIZ)
+	.ECHO	"*** INVALID PPA CONFIG TABLE ***\n"
+#ENDIF
+;
+	.DB	$FF			; END MARKER
--- a/Source/HBIOS/ppp.asm
+++ b/Source/HBIOS/ppp.asm
@@ -904,7 +904,7 @@ PPPSD_GETCSD:
 	CALL	PPP_SNDCMD		; SEND COMMAND
 	RET	NZ			; ABORT ON ERROR

-	LD	B,16			; GET 4 BYTES
+	LD	B,16			; GET 16 BYTES
 	LD	HL,PPPSD_CSDBUF
 PPPSD_GETCSD1:
 	CALL	PPP_GETBYTE
--- a/Source/HBIOS/std.asm
+++ b/Source/HBIOS/std.asm
@@ -248,6 +248,16 @@ LPTMODE_NONE	.EQU	0		; NONE
 LPTMODE_IBM	.EQU	1		; IBM STYLE INTERFACE
 LPTMODE_MG014	.EQU	2		; RCBUS MG014 STYLE INTERFACE
 ;
+; PPA DRIVER MODE SELECTIONS
+;
+PPAMODE_NONE	.EQU	0		; NONE
+PPAMODE_MG014	.EQU	1		; RCBUS MG014 STYLE INTERFACE
+;
+; IMM DRIVER MODE SELECTIONS
+;
+IMMMODE_NONE	.EQU	0		; NONE
+IMMMODE_MG014	.EQU	1		; RCBUS MG014 STYLE INTERFACE
+;
 ; GDC MONITOR SELECTIONS
 ;
 GDCMON_NONE	.EQU	0
@@ -437,6 +447,16 @@ SPD_UNSUP	.EQU	0		; PLATFORM CAN CHANGE SPEEDS BUT IS UNSUPPORTED
 SPD_HIGH	.EQU	1		; PLATFORM CAN CHANGE SPEED, STARTS HIGH
 SPD_LOW		.EQU	2		; PLATFORM CAN CHANGE SPEED, STARTS LOW
 ;
+; SCSI COMMAND CODES (SHOULD BE IT IT'S OWN FILE)
+;
+SCSI_CMD_READ	.EQU	$08
+SCSI_CMD_INQ	.EQU	$12
+SCSI_CMD_TEST	.EQU	$00
+SCSI_CMD_START	.EQU	$1B
+SCSI_CMD_SENSE	.EQU	$03
+SCSI_CMD_WRITE	.EQU	$0A
+SCSI_CMD_RDCAP	.EQU	$25
+;
 #INCLUDE "build.inc"		; INCLUDE USER CONFIG, ADD VARIANT, TIMESTAMP, & ROMSIZE
 ;
 ; INCLUDE Z180 REGISTER DEFINITIONS
--- a/Source/pSys/ReadMe.txt
+++ b/Source/pSys/ReadMe.txt
@@ -48,7 +48,7 @@ The layout of the first track does not conform exactly to the
 recommended p-System layout.  The recommended layout is not possible 
 because it conflicts with the RomWBW definition for a boot track.  
 However, the changes are only slightly different sector assignments for 
-the different boot componets -- the general boot sequence and mechanism 
+the different boot components -- the general boot sequence and mechanism 
 for the p-System is completely standard.

 The logical disk geometry used by this p-System
@@ -77,14 +77,17 @@ escape sequence handling configuration.  The debugger code as added to
 SYSTEM.PASCAL to enable the debug function.  SYSTEM.INTERP was modified 
 to enable the extended BIOS functions.

-The build/makefile creates the psys disk image (psys.img) by adding 
-concatentating psys.vol and blank.vol (after adding track 0 contents to 
+The build/makefile creates the psys disk image (psys.img) by 
+concatenating psys.vol and blank.vol (after adding track 0 contents to 
 each).  psys.vol and blank.vol are recognized by CiderPress and 
 CiderPress can be used to add/remove files from these volumes.  
-However, there is currently no straightforward way to extract the 
-volumes from the disk image.  If you are good with a binary disk 
-editor, you can do it that way.  Please contact me if you are 
-interested in pursuing that.
+To extract volumes from a disk image, Andrew Davidson has created
+a nice Python script that can extract p-System volumes from an
+existing disk image file.  The extracted volume can be manipulated
+by CiderPress.  The script is also capable of re-inserting a modified
+volume back into the disk image file.  This tool is available at:
+https://github.com/robosnacks/psysimg.
+

 There is currently no support for floppy drives.

@@ -119,7 +122,7 @@ that SofTech produced a IV.1 with some nice enhancements (like
 subsidiary volumes and decent support for ANSI/VT-100 terminals).  I
 have been unable to track down the IV.1 distribution media despite
 trying very hard.  If anyone knows of a source for the media of the
-Adapable p-System for Z80, I would love to get hold of it.
+Adaptable p-System for Z80, I would love to get hold of it.

 3:58 PM Tuesday, January 17, 2023

@@ -138,4 +141,10 @@ arrow keys transmitted by an ANSI/VT-100 terminal.  In this case,
 the setup program was used to define up/down/left/right like
 WordStar does: ^E,^X,^S,^D.

-5:48 PM Tuesday, January 17, 2023
+5:48 PM Tuesday, January 17, 2023
+
+Updated instructions above to include a reference to Andrew 
+Davidson's Python script that will extract/insert volumes from/to
+a disk image.
+
+1:31 PM Thursday, May 11, 2023
--- a/Source/pSys/psys.vol
+++ b/Source/pSys/psys.vol
--- a/Source/ver.inc
+++ b/Source/ver.inc
@@ -2,7 +2,7 @@
 #DEFINE	RMN	3
 #DEFINE	RUP	0
 #DEFINE	RTP	0
-#DEFINE BIOSVER	"3.3.0-dev.13"
+#DEFINE BIOSVER	"3.3.0-dev.16"
 #define rmj	RMJ
 #define rmn	RMN
 #define rup	RUP
--- a/Source/ver.lib
+++ b/Source/ver.lib
@@ -3,5 +3,5 @@ rmn	equ	3
 rup	equ	0
 rtp	equ	0
 biosver	macro
-	db	"3.3.0-dev.13"
+	db	"3.3.0-dev.16"
 	endm