Small Bug Fix for PPA/IMM/SYQ Drivers

Credit to Mark Elkin for testing and finding this issue.

Doc/ChangeLog.txt

@@ -7,7 +7,9 @@ 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)
+- WBW: Support for EMM Zip Drive on PPI interface (much inspiration from Alan Cox)
+- WBW: Support for PPA Zip Drive on PPI interface (much inspiration from Alan Cox)
+- WBW: Support for SyQuest SparQ Drive on PPI interface (much inspiration from Alan Cox)
 
 Version 3.2.1
 -------------

ReadMe.md

@@ -3,7 +3,7 @@
 **RomWBW ReadMe** \
 Version 3.3 \
 Wayne Warthen  ([wwarthen@gmail.com](mailto:wwarthen@gmail.com)) \
-23 May 2023
+02 Jun 2023
 
 # Overview
 

ReadMe.txt

@@ -1,6 +1,6 @@
 RomWBW ReadMe
 Wayne Warthen (wwarthen@gmail.com)
-23 May 2023
+02 Jun 2023
 
 
 

Source/Doc/UserGuide.md

@@ -3901,6 +3901,7 @@ may be discovered by RomWBW in your system.
 | GDC       | Video    | uPD7220 Video Display Controller                       |
 | HDSK      | Disk     | SIMH Simulator Hard Disk                               |
 | IDE       | Disk     | IDE/ATA Hard Disk Interface                            |
+| IMM       | Disk     | IMM Zip Drive on PPI                                   |
 | INTRTC    | RTC      | Interrupt-based Real Time Clock                        |
 | KBD       | Kbd      | 8242 PS/2 Keyboard Controller                          |
 | KIO       | System   | Zilog Serial/ Parallel Counter/Timer                   |
@@ -3910,6 +3911,7 @@ may be discovered by RomWBW in your system.
 | I2C       | System   | I2C Interface                                          |
 | PIO       | Char     | Zilog Parallel Interface Controller                    |
 | PPIDE     | Disk     | 8255 IDE/ATA Hard Disk Interface                       |
+| PPA       | Disk     | PPA Zip Drive on PPI                                   |
 | PPK       | Kbd      | Matrix Keyboard                                        |
 | PPPSD     | Disk     | ParPortProp SD Card Interface                          |
 | PPPCON    | Serial   | ParPortProp Serial Console Interface                   |
@@ -3922,6 +3924,7 @@ may be discovered by RomWBW in your system.
 | SIO       | Char     | Zilog Serial Port Interface                            |
 | SN76489   | Sound    | SN76489 Programmable Sound Generator                   |
 | SPK       | Sound    | Bit-bang Speaker                                       |
+| SYQ       | Disk     | Iomega SparQ Drive on PPI                              |
 | TMS       | Video    | TMS9918/38/58 Video Display Controller                 |
 | UART      | Char     | 16C550 Family Serial Interface                         |
 | USB-FIFO  | Char     | FT232H-based ECB USB FIFO                              |

Source/HBIOS/imm.asm

@@ -9,7 +9,7 @@
 ; INTENDED TO CO-EXIST WITH LPT DRIVER.
 ;
 ; CREATED BY WAYNE WARTHEN FOR ROMWBW HBIOS.
-; MUCH OF THE CODE IS DERIVED FROM FUZIX (ALAN COX).
+; MUCH OF THE CODE IS DERIVED FROM LINUX AND FUZIX (ALAN COX).
 ;
 ; 5/23/2023 WBW - INITIAL RELEASE
 ; 5/26/2023 WBW - CLEAN UP, LED ACTIVITY
@@ -189,7 +189,7 @@ IMM_INIT4:
 	CALL	DIO_ADDENT		; ADD ENTRY TO GLOBAL DISK DEV TABLE
 ;
 	CALL	IMM_RESET		; RESET/INIT THE INTERFACE
-#IF (IMMTRACE == 0)
+#IF (IMMTRACE <= 1)
 	CALL	IMM_PRTSTAT
 #ENDIF
 	JR	NZ,IMM_INIT6
@@ -224,6 +224,9 @@ IMM_INIT6:
 ; ON RETURN, ZF SET INDICATES HARDWARE FOUND
 ;
 IMM_DETECT:
+#IF (IMMTRACE >= 3)
+	PRTS("\r\nDETECT:$")
+#ENDIF
 	; INITIALIZE 8255
 	LD	A,(IY+IMM_IOBASE)	; BASE PORT
 	ADD	A,IMM_IOSETUP		; BUMP TO SETUP PORT
@@ -232,28 +235,51 @@ IMM_DETECT:
 	OUT	(C),A			; DO IT
 	CALL	DELAY			; BRIEF DELAY FOR GOOD MEASURE
 ;
-	; WE USE THIS SEQUENCE TO DETECT AN ACTUAL IMM DEVICE ON THE
-	; PARALLEL PORT.  THE VALUES RECORDED IN THE FINAL CALL TO
-	; IMM_DISCONNECT ARE USED TO CONFIRM DEVICE PRESENCE.
-	; NO ACTUAL SCSI COMMANDS ARE USED.
+	; ATTEMPT TO ESTABLISH A CONNECTION TO THE IMM DEVICE AND
+	; ISSUE A SCSI BUS RESET.  WE DON'T KNOW IF DEVICE IS THERE
+	; YET.  THIS IS DONE BLIND ASSUMING IT IS THERE.
 	CALL	IMM_DISCONNECT
 	CALL	IMM_CONNECT
+	CALL	IMM_RESETPULSE		; ISSUE A SCSI BUS RESET
+	LD	DE,62			; WAIT A BIT
+	CALL	VDELAY
+;
+	; USE AN ABBREVIATED VERSION OF SELECT PROCESSING TO
+	; CHECK IF DEVICE EXISTS.
+	IMM_WCTL($0C)
+	CALL	IMM_READSTATUS
+;
+#IF (IMMTRACE >= 3)
+	CALL	PC_SPACE
+	CALL	PRTHEXBYTE
+#ENDIF
+;
+	; READY FOR SELECT?
+	AND	$08
+	CP	$00
+	JR	NZ,IMM_DETECT1
+;
+	IMM_WCTL($04)
+	LD	A,$80 | (1 << IMM_TGT)
+	CALL	IMM_WRITEDATA
+	IMM_WCTL($0C)
+	IMM_WCTL($0D)
+	CALL	DELAY
+	CALL	IMM_READSTATUS
+;
+#IF (IMMTRACE >= 3)
+	CALL	PC_SPACE
+	CALL	PRTHEXBYTE
+#ENDIF
+;
+	; DID SELECT SUCCEED?
+	AND	$08
+	CP	$08
+;
+IMM_DETECT1:
+	PUSH	AF
 	CALL	IMM_DISCONNECT
-;
-	; THE IMM_SN VALUES ARE RECORDED IN THE CPP ROUTINE USED BY
-	; IMM_CONNECT/DISCONNECT.
-	; EXPECTING S1=$B8, S2=$18, S3=$38
-	LD	A,(IMM_S1)
-	CP	$B8
-	RET	NZ
-	LD	A,(IMM_S2)
-	CP	$18
-	RET	NZ
-	LD	A,(IMM_S3)
-	CP	$38
-	RET	NZ
-;
-	XOR	A
+	POP	AF
 	RET
 ;
 ;=============================================================================
@@ -302,10 +328,12 @@ IMM_WRITE:
 ;
 ;
 IMM_IO:
-	LD	(IMM_DSKBUF),HL		; SAVE DISK BUFFER ADDRESS
+	PUSH	HL
 	CALL	IMM_CHKERR		; CHECK FOR ERR STATUS AND RESET IF SO
+	POP	HL
 	JR	NZ,IMM_IO3		; BAIL OUT ON ERROR
 ;
+	LD	(IMM_DSKBUF),HL		; SAVE DISK BUFFER ADDRESS
 	; SETUP LBA
 	; 3 BYTES, LITTLE ENDIAN -> BIG ENDIAN
 	LD	HL,IMM_CMD_RW+1		; START OF LBA FIELD IN CDB (MSB)
@@ -607,6 +635,10 @@ IMM_SELECT:
 ;
 IMM_SELECT1:
 	CALL	IMM_READSTATUS
+#IF (IMMTRACE >= 3)
+	CALL	PC_SPACE
+	CALL	PRTHEXBYTE
+#ENDIF
 	AND	$08
 	JR	Z,IMM_SELECT2		; IF CLEAR, MOVE ON
 	DEC	HL
@@ -620,22 +652,8 @@ IMM_SELECT2:
 	; PLACE HOST AND TARGET BIT ON DATA BUS
 	LD	A,$80 | (1 << IMM_TGT)
 	CALL	IMM_WRITEDATA
-	CALL	DELAY			; CONFIRM DELAY TIME?
 	IMM_WCTL($0C)
-;
-#IF (IMMTRACE >= 3)
-	CALL	IMM_READSTATUS
-	CALL	PC_SPACE
-	CALL	PRTHEXBYTE
-#ENDIF
-;
 	IMM_WCTL($0D)
-;
-#IF (IMMTRACE >= 3)
-	CALL	IMM_READSTATUS
-	CALL	PC_SPACE
-	CALL	PRTHEXBYTE
-#ENDIF
 ;
 	LD	HL,500			; TIMEOUT COUNTER
 ;
@@ -1024,7 +1042,7 @@ IMM_GETSTATUS:
 ;
 	RET
 ;
-; TERMINATE A BULD READ OPERATION
+; TERMINATE A BULK READ OPERATION
 ;
 IMM_ENDREAD:
 	IMM_WCTL($04)
@@ -1151,7 +1169,8 @@ IMM_CHKCMD1:
 ;
 	; REQ SENSE CMD COMPLETED
 #IF (IMMTRACE >= 3)
-	LD	A,16
+	PRTS("\r\nSENSE:$")
+	LD	A,$19
 	LD	DE,HB_WRKBUF
 	CALL	Z,PRTHEXBUF
 #ENDIF
@@ -1219,7 +1238,8 @@ IMM_INITDEV1:
 	JR	NZ,IMM_INITDEV2		; IF ERROR, LOOP
 ;
 #IF (IMMTRACE >= 3)
-	LD	A,16
+	PRTS("\r\nSENSE:$")
+	LD	A,$19
 	LD	DE,HB_WRKBUF
 	CALL	PRTHEXBUF
 #ENDIF
@@ -1241,9 +1261,10 @@ IMM_INITDEV3:
 	LD	HL,IMM_CMD_RDCAP	; POINT TO READ CAPACITY CMD
 	CALL	IMM_RUNCMD		; RUN THE SCSI ENGINE
 	CALL	Z,IMM_CHKCMD		; CHECK AND RECORD ANY ERRORS
-	RET	NZ			; BAIL ON ON ERROR
+	RET	NZ			; BAIL OUT ON ERROR
 ;
 #IF (IMMTRACE >= 3)
+	PRTS("\r\nRDCAP:$")
 	LD	A,8
 	LD	DE,HB_WRKBUF
 	CALL	PRTHEXBUF
@@ -1302,7 +1323,7 @@ IMM_ERR:
 	LD	(IY+IMM_STAT),A		; SAVE NEW STATUS
 ;
 IMM_ERR2:
-#IF (IMMTRACE >= 1)
+#IF (IMMTRACE >= 2)
 	CALL	IMM_PRTSTAT
 #ENDIF
 	OR	A			; SET FLAGS

Source/HBIOS/ppa.asm

@@ -9,7 +9,7 @@
 ; INTENDED TO CO-EXIST WITH LPT DRIVER.
 ;
 ; CREATED BY WAYNE WARTHEN FOR ROMWBW HBIOS.
-; MUCH OF THE CODE IS DERIVED FROM FUZIX (ALAN COX).
+; MUCH OF THE CODE IS DERIVED FROM LINUX AND FUZIX (ALAN COX).
 ;
 ; 5/23/2023 WBW - INITIAL RELEASE
 ; 5/26/3023 WBW - CLEAN UP, LED ACTIVITY
@@ -71,8 +71,6 @@
 ;
 ; TODO:
 ;
-; - CURRENTLY HAS ONLY DETECTION LOGIC.  NEED TO WRITE THE REST!!!
-;
 ; - OPTIMIZE READ/WRITE LOOPS
 ;
 ; NOTES:
@@ -137,6 +135,9 @@ PPA_LBA		.EQU	8		; OFFSET OF LBA (DWORD)
 #DEFINE PPA_WCTL(VAL)	LD A,VAL \ CALL PPA_WRITECTRL
 #DEFINE PPA_WDATA(VAL)	LD A,VAL \ CALL PPA_WRITEDATA
 ;
+#DEFINE PPA_DPUL(VAL)	LD A,VAL \ CALL PPA_DPULSE
+#DEFINE PPA_CPUL(VAL)	LD A,VAL \ CALL PPA_CPULSE
+;
 ;=============================================================================
 ; INITIALIZATION ENTRY POINT
 ;=============================================================================
@@ -192,7 +193,7 @@ PPA_INIT4:
 	CALL	DIO_ADDENT		; ADD ENTRY TO GLOBAL DISK DEV TABLE
 ;
 	CALL	PPA_RESET		; RESET/INIT THE INTERFACE
-#IF (PPATRACE == 0)
+#IF (PPATRACE <= 1)
 	CALL	PPA_PRTSTAT
 #ENDIF
 	JR	NZ,PPA_INIT6
@@ -227,6 +228,9 @@ PPA_INIT6:
 ; ON RETURN, ZF SET INDICATES HARDWARE FOUND
 ;
 PPA_DETECT:
+#IF (PPATRACE >= 3)
+	PRTS("\r\nDETECT:$")
+#ENDIF
 	; INITIALIZE 8255
 	LD	A,(IY+PPA_IOBASE)	; BASE PORT
 	ADD	A,PPA_IOSETUP		; BUMP TO SETUP PORT
@@ -235,34 +239,37 @@ PPA_DETECT:
 	OUT	(C),A			; DO IT
 	CALL	DELAY			; BRIEF DELAY FOR GOOD MEASURE
 ;
-	LD	A,$AA \ CALL	PPA_WRITEDATA
+	PPA_WDATA($AA)
 	CALL	PPA_DISCONNECT
 	CALL	PPA_CONNECT
-	LD	A,$06 \ CALL	PPA_WRITECTRL
+	PPA_WCTL($0E)
 	CALL	PPA_READSTATUS
 ;
+#IF (PPATRACE >= 3)
 	CALL	PC_SPACE
 	CALL	PRTHEXBYTE
+#ENDIF
 ;
-	AND	$F0
-	CP	$F0
+	AND	$08
+	CP	$08
 	JR	NZ,PPA_DETECT_FAIL
-	LD	A,$04 \ CALL	PPA_WRITECTRL
+;
+	PPA_WCTL($0C)
 	CALL	PPA_READSTATUS
 ;
+#IF (PPATRACE >= 3)
 	CALL	PC_SPACE
 	CALL	PRTHEXBYTE
+#ENDIF
 ;
-	AND	$F0
-	CP	$80
+	AND	$08
+	CP	$00
 	JR	NZ,PPA_DETECT_FAIL
-	LD	A,$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,$0C \ CALL	PPA_WRITECTRL
+;
 	CALL	PPA_DISCONNECT
+;
+	PPA_WDATA($AA)
+	PPA_WCTL($0C)
 ;
 	XOR	A			; SIGNAL SUCCESS
 	RET				; AND RETURN
@@ -270,7 +277,6 @@ PPA_DETECT:
 PPA_DETECT_FAIL:
 	OR	$FF			; SIGNAL FAILURE
 	RET	NZ
-
 ;
 ;=============================================================================
 ; DRIVER FUNCTION TABLE
@@ -318,10 +324,12 @@ PPA_WRITE:
 ;
 ;
 PPA_IO:
-	LD	(PPA_DSKBUF),HL		; SAVE DISK BUFFER ADDRESS
+	PUSH	HL
 	CALL	PPA_CHKERR		; CHECK FOR ERR STATUS AND RESET IF SO
+	POP	HL
 	JR	NZ,PPA_IO3		; BAIL OUT ON ERROR
 ;
+	LD	(PPA_DSKBUF),HL		; SAVE DISK BUFFER ADDRESS
 	; SETUP LBA
 	; 3 BYTES, LITTLE ENDIAN -> BIG ENDIAN
 	LD	HL,PPA_CMD_RW+1		; START OF LBA FIELD IN CDB (MSB)
@@ -447,32 +455,6 @@ PPA_GEOM:
 ; 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,PPA_CMD_TIMEOUT	; TIMEOUT
-	JR	PPA_WAITDONE1
-;
 ; OUTPUT BYTE IN A TO THE DATA PORT
 ;
 PPA_WRITEDATA:
@@ -548,64 +530,91 @@ PPA_READSTATUS5:
 ;
 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
+	PPA_WCTL($0C)
+	PPA_WCTL($0E)
+	PPA_WCTL($0C)
+	PPA_WCTL($04)
+	PPA_WCTL($0C)
 	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
+	PPA_WCTL($04)
+	PPA_WCTL($06)
+	PPA_WCTL($04)
+	PPA_WCTL($0C)
 	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
+	PPA_CPUL($00)
+	PPA_CPUL($3C)
+	PPA_CPUL($20)
+	PPA_CPUL($8F)
 	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
+	PPA_DPUL($00)
+	PPA_DPUL($3C)
+	PPA_DPUL($20)
+	PPA_DPUL($0F)
+;
+	; TURNS OFF MG014 LED
+	PPA_WCTL($8C)
+;
+	RET
+;
+; INITIATE A SCSI BUS RESET.
+;
+PPA_RESETPULSE:
+	PPA_WDATA($40)
+	PPA_WCTL($08)
+	CALL	DELAY		; 32 US, IDEALLY 30 US
+	PPA_WCTL($0C)
 	RET
 ;
 ; SCSI SELECT PROCESS
 ;
-;
 PPA_SELECT:
+#IF (PPATRACE >= 3)
+	PRTS("\r\nSELECT: $")
+#ENDIF
+;
+#IF (PPATRACE >= 3)
+	CALL	PPA_READSTATUS
+	CALL	PC_SPACE
+	CALL	PRTHEXBYTE
+#ENDIF
+;
 	LD	A,1 << PPA_TGT
 	CALL	PPA_WRITEDATA
-	LD	A,$0E \ CALL	PPA_WRITECTRL
-	LD	A,$0C \ CALL	PPA_WRITECTRL
+	PPA_WCTL($0E)
+	PPA_WCTL($0C)
 	LD	A,1 << PPA_SELF
 	CALL	PPA_WRITEDATA
-	LD	A,$08 \ CALL	PPA_WRITECTRL
+	PPA_WCTL($08)
 ;
-	LD	HL,0			; TIMEOUT COUNTER
+	LD	HL,500			; TIMEOUT COUNTER
 ;
 PPA_SELECT1:
+#IF (PPATRACE >= 3)
 	CALL	PPA_READSTATUS
-	OR	$F0
-	RET	NZ
+	CALL	PC_SPACE
+	CALL	PRTHEXBYTE
+#ENDIF
+	AND	$40
+	CP	$40
+	RET	Z
 	DEC	HL
 	LD	A,H
 	OR	L
-	RET	Z			; TIMEOUT
-	JR	PPA_SELECT1
+	JR	NZ,PPA_SELECT1
+	JP	PPA_CMD_TIMEOUT
 ;
 ; SEND SCSI CMD BYTE STRING.  AT ENTRY, HL POINTS TO START OF
 ; COMMAND BYTES.  THE LENGTH OF THE COMMAND STRING MUST PRECEED
@@ -615,7 +624,313 @@ PPA_SELECT1:
 ; DATA OUTPOUT IS BURSTED (NO CHECK FOR BUSY).  SEEMS TO WORK FINE.
 ;
 PPA_SENDCMD:
-	JP	PPA_ERR			; NOW DO STANDARD ERR PROCESSING
+;
+#IF (PPATRACE >= 3)
+	PRTS("\r\nSENDCMD:$")
+#ENDIF
+;
+	DEC	HL		; BACKUP TO LENGTH BYTE
+	LD	B,(HL)		; PUT IN B FOR LOOP COUNTER
+;
+#IF (PPATRACE >= 3)
+	LD	A,B
+	CALL	PC_SPACE
+	CALL	PRTHEXBYTE
+	PRTS(" BYTES$")
+#ENDIF
+;
+	INC	HL		; BACK TO FIRST CMD BYTE
+;
+PPA_SENDCMD1:
+	;PPA_WCTL($0C)
+	LD	A,(HL)		; LOAD CMD BYTE
+;
+#IF (PPATRACE >= 3)
+	CALL	PC_SPACE
+	CALL	PRTHEXBYTE
+#ENDIF
+;
+	CALL	PPA_WRITEDATA	; PUT IT ON THE BUS
+	INC	HL		; BUMP TO NEXT BYTE
+	PPA_WCTL($0E)
+	PPA_WCTL($0C)
+	DJNZ	PPA_SENDCMD1	; LOOP TILL DONE
+;
+	RET
+;
+;
+;
+;
+; WAIT FOR SCSI BUS TO BECOME READY WITH A TIMEOUT.
+;
+PPA_WAITLOOP:
+	CALL	PPA_READSTATUS
+	BIT	7,A
+	RET	NZ			; DONE, STATUS IN A
+	DEC	HL
+	LD	A,H
+	OR	L
+	RET	Z			; TIMEOUT
+	JR	PPA_WAITLOOP
+;
+PPA_WAIT:
+	LD	HL,500			; GOOD VALUE???
+	PPA_WCTL($0C)
+	CALL	PPA_WAITLOOP
+
+	;CALL	PC_SPACE
+	;CALL	PRTHEXBYTE
+
+	JP	Z,PPA_CMD_TIMEOUT	; HANDLE TIMEOUT
+	;PUSH	AF
+	;PPA_WCTL($04)
+	;POP	AF
+	AND	$F0
+	RET				; RETURN W/ RESULT IN A
+;
+; MAX OBSERVED PPA_WAITLOOP ITERATIONS IS $0116B3
+;
+PPA_LONGWAIT:
+	LD	B,3			; VALUE???
+	PPA_WCTL($0C)
+PPA_LONGWAIT1:
+	LD	HL,0
+	CALL	PPA_WAITLOOP
+	JR	NZ,PPA_LONGWAIT2	; HANDLE SUCCESS
+	DJNZ	PPA_LONGWAIT1		; LOOP TILL COUNTER EXHAUSTED
+
+	;CALL	PC_SPACE
+	;CALL	PRTHEXBYTE
+
+	JP	PPA_CMD_TIMEOUT		; HANDLE TIMEOUT
+;
+PPA_LONGWAIT2:
+	;PUSH	AF
+	;PPA_WCTL($04)
+;
+#IF 0
+	PUSH	AF
+	CALL	PC_GT
+	LD	A,B
+	CALL	PRTHEXBYTE
+	CALL	PC_COLON
+	CALL	PRTHEXWORDHL
+	POP	AF
+#ENDIF
+;
+	;POP	AF
+
+	;CALL	PC_SPACE
+	;CALL	PRTHEXBYTE
+
+	AND	$F0
+	RET				; RETURN W/ RESULT IN A
+;
+; GET A BYTE OF DATA FROM THE SCSI DEVICE.  THIS IS A NIBBLE READ.
+; BYTE RETURNED IN A.
+;
+PPA_GETBYTE:
+	CALL	PPA_WAIT
+	PPA_WCTL($04)
+	CALL	PPA_READSTATUS
+	AND	$F0
+	PUSH 	AF
+	PPA_WCTL($06)
+	CALL	PPA_READSTATUS
+	AND	$F0
+	RRCA
+	RRCA
+	RRCA
+	RRCA
+	POP	HL
+	OR	H
+	PUSH	AF
+	PPA_WCTL($0C)
+	POP	AF
+	RET
+;
+; GET A CHUNK OF DATA FROM SCSI BUS.  THIS IS SPECIFICALLY FOR
+; READ PHASE.  IF A LENGTH IS SPECIFIED (NON-ZERO HL), THEN THE
+; DATA IS BURST READ.  IF NO LENGTH SPECIFIED, DATA IS READ AS
+; LONG AS SCSI DEVICE WANTS TO CONTINUE SENDING (NO OVERRUN
+; CHECK IN THIS CASE).
+;
+; THIS IS A NIBBLE READ.
+;
+; DE=BUFFER
+; HL=LENGTH (0 FOR VARIABLE)
+;
+PPA_GETDATA:
+	; BRANCH TO CORRECT ROUTINE
+	LD	A,H
+	OR	L			; IF ZERO
+	JR	NZ,PPA_GETDATALEN	; DO BURST READ
+;
+#IF (PPATRACE >= 3)
+	PRTS("\r\nGETDATA:$")
+#ENDIF
+;
+PPA_GETDATA1:
+	PUSH	HL			; SAVE BYTE COUNTER
+	CALL	PPA_WAIT		; WAIT FOR BUS READY
+	POP	HL			; RESTORE BYTE COUNTER
+	CP	$D0			; CHECK FOR READ PHASE
+	JR	NZ,PPA_GETDATA2		; IF NOT, ASSUME WE ARE DONE
+	PPA_WCTL($04)
+	CALL	PPA_READSTATUS		; GET FIRST NIBBLE
+	AND	$F0			; ISOLATE BITS
+	PUSH 	AF			; SAVE WORKING VALUE
+	PPA_WCTL($06)
+	CALL	PPA_READSTATUS		; GET SECOND NIBBLE
+	AND	$F0			; ISOLATE BITS
+	RRCA				; AND SHIFT TO LOW NIBBLE
+	RRCA
+	RRCA
+	RRCA
+	POP	BC			; RECOVER LOW NIBBLE
+	OR	B			; COMBINE
+	LD	(DE),A			; AND SAVE THE FULL BYTE VALUE
+	INC	DE			; NEXT BUFFER POS
+	INC	HL			; INCREMENT BYTES COUNTER
+	JR	PPA_GETDATA1		; LOOP TILL DONE
+;
+PPA_GETDATA2:
+;
+#IF (PPATRACE >= 3)
+	CALL	PC_SPACE
+	CALL	PRTHEXWORDHL
+	PRTS(" BYTES$")
+#ENDIF
+;
+	PPA_WCTL($0C)
+	RET
+;
+PPA_GETDATALEN:
+;
+#IF (PPATRACE >= 3)
+	PRTS("\r\nGETDLEN:$")
+	CALL	PC_SPACE
+	CALL	PRTHEXWORDHL
+	PRTS(" BYTES$")
+#ENDIF
+;
+PPA_GETDATALEN1:
+	PPA_WCTL($04)
+	CALL	PPA_READSTATUS		; GET FIRST NIBBLE
+	AND	$F0			; ISOLATE BITS
+	PUSH 	AF			; SAVE WORKING VALUE
+	PPA_WCTL($06)
+	CALL	PPA_READSTATUS		; GET SECOND NIBBLE
+	AND	$F0			; ISOLATE BITS
+	RRCA				; MOVE TO LOW NIBBLE
+	RRCA
+	RRCA
+	RRCA
+	POP	BC			; RECOVER FIRST NIBBLE
+	OR	B			; COMBINE
+	LD	(DE),A			; SAVE FINAL BYTE VALUE
+	INC	DE			; NEXT BUFFER POS
+	DEC	HL			; DEC LOOP COUNTER
+	LD	A,H			; CHECK LOOP COUNTER
+	OR	L
+	JR	NZ,PPA_GETDATALEN1	; LOOP IF NOT DONE
+	PPA_WCTL($0C)
+	RET
+;
+; PUT A CHUNK OF DATA TO THE SCSI BUS.  THIS IS SPECIFICALLY FOR
+; WRITE PHASE.  IF A LENGTH IS SPECIFIED (NON-ZERO HL), THEN THE
+; DATA IS BURST WRITTEN.  IF NO LENGTH SPECIFIED, DATA IS WRITTEN AS
+; LONG AS SCSI DEVICE WANTS TO CONTINUE RECEIVING (NO OVERRUN
+; CHECK IN THIS CASE).
+;
+; READS ARE DONE AS BYTE PAIRS.  EACH LOOP READS 2 BYTES.
+;
+; DE=BUFFER
+; HL=LENGTH (0 FOR VARIABLE)
+;
+PPA_PUTDATA:
+	LD	A,H
+	OR	L
+	JR	NZ,PPA_PUTDATALEN
+;
+#IF (PPATRACE >= 3)
+	PRTS("\r\nPUTDATA:$")
+#ENDIF
+;
+PPA_PUTDATA1:
+	PUSH	HL			; SAVE BYTE COUNTER
+	CALL	PPA_WAIT		; WAIT FOR BUS READY
+	POP	HL			; RESTORE BYTE COUNTER
+	CP	$C0			; CHECK FOR WRITE PHASE
+	JR	NZ,PPA_PUTDATA2		; IF NOT, ASSUME WE ARE DONE
+	LD	A,(DE)			; GET NEXT BYTE TO WRITE (FIRST OF PAIR)
+	CALL	PPA_WRITEDATA		; PUT ON BUS
+	INC	DE			; BUMP TO NEXT BUF POS
+	INC	HL			; INCREMENT COUNTER
+	PPA_WCTL($0E)
+	PPA_WCTL($0C)
+	LD	A,(DE)			; GET NEXT BYTE TO WRITE (SECOND OF PAIR)
+	JR	PPA_PUTDATA1		; LOOP TILL DONE
+;
+PPA_PUTDATA2:
+;
+#IF (PPATRACE >= 3)
+	CALL	PC_SPACE
+	CALL	PRTHEXWORDHL
+	PRTS(" BYTES$")
+#ENDIF
+;
+	RET
+;
+PPA_PUTDATALEN:
+;
+#IF (PPATRACE >= 3)
+	PRTS("\r\nPUTDLEN:$")
+	CALL	PC_SPACE
+	CALL	PRTHEXWORDHL
+	PRTS(" BYTES$")
+#ENDIF
+;
+PPA_PUTDATALEN1:
+	LD	A,(DE)			; GET NEXT BYTE (FIRST OF PAIR)
+	CALL	PPA_WRITEDATA		; PUT ON BUS
+	INC	DE			; INCREMENT BUF POS
+	DEC	HL			; DEC LOOP COUNTER
+	PPA_WCTL($0E)
+	PPA_WCTL($0C)
+	LD	A,H			; CHECK LOOP COUNTER
+	OR	L
+	JR	NZ,PPA_PUTDATALEN1	; LOOP TILL DONE
+	RET
+;
+; READ SCSI COMMAND STATUS
+;
+PPA_GETSTATUS:
+;
+#IF (PPATRACE >= 3)
+	PRTS("\r\nSTATUS:$")
+#ENDIF
+;
+	CALL	PPA_GETBYTE		; GET ONE BYTE
+	LD	(PPA_CMDSTAT),A		; SAVE AS FIRST STATUS BYTE
+;
+#IF (PPATRACE >= 3)
+	CALL	PC_SPACE
+	CALL	PRTHEXBYTE
+#ENDIF
+;
+	CALL	PPA_WAIT		; CHECK FOR OPTIONAL SECOND BYTE
+	CP	$F0			; STILL IN STATUS PHASE?
+	RET	NZ			; IF NOT, DONE
+	CALL	PPA_GETBYTE		; ELSE, GET THE SECOND BYTE
+	LD	(PPA_CMDSTAT+1),A	; AND SAVE IT
+;
+#IF (PPATRACE >= 3)
+	CALL	PC_SPACE
+	CALL	PRTHEXBYTE
+#ENDIF
+;
+	RET
 ;
 ; THIS IS THE MAIN SCSI ENGINE.  BASICALLY, IT SELECTS THE DEVICE
 ; ON THE BUS, SENDS THE COMMAND, THEN PROCESSES THE RESULT.
@@ -625,6 +940,83 @@ PPA_SENDCMD:
 ; BC: TRANSFER LENGTH (0=VARIABLE)
 ;
 PPA_RUNCMD:
+	; THERE ARE MANY PLACES NESTED WITHIN THE ROUTINES THAT
+	; ARE CALLED HERE.  HERE WE SAVE THE STACK SO THAT WE CAN
+	; EASILY AND QUICKLY ABORT OUT OF ANY NESTED ROUTINE.
+	; SEE PPA_CMD_ERR BELOW.
+	LD	(PPA_CMDSTK),SP		; FOR ERROR ABORTS
+	LD	(PPA_DSKBUF),DE		; SAVE BUF PTR
+	LD	(PPA_XFRLEN),BC		; SAVE XFER LEN
+	PUSH	HL
+	CALL	PPA_CONNECT		; PARALLEL PORT BUS CONNECT
+	CALL	PPA_SELECT		; SELECT TARGET DEVICE
+	CALL	PPA_WAIT		; WAIT TILL READY
+	POP	HL
+	CALL	PPA_SENDCMD		; SEND THE COMMAND
+;
+PPA_RUNCMD_PHASE:
+	; WAIT FOR THE BUS TO BE READY.  WE USE AN EXTRA LONG WAIT
+	; TIMEOUT HERE BECAUSE THIS IS WHERE WE WILL WAIT FOR LONG
+	; OPERATIONS TO COMPLETE.  IT CAN TAKE SOME TIME IF THE
+	; DEVICE HAS GONE TO SLEEP BECAUSE IT WILL NEED TO WAKE UP
+	; AND SPIN UP BEFORE PROCESSING AN I/O COMMAND.
+	CALL	PPA_LONGWAIT		; WAIT TILL READY
+;
+#IF (PPATRACE >= 3)
+	PRTS("\r\nPHASE: $")
+	CALL	PRTHEXBYTE
+#ENDIF
+;
+	CP	$C0			; DEVICE WANTS TO RCV DATA
+	JR	Z,PPA_RUNCMD_WRITE
+	CP	$D0			; DEVICE WANTS TO SEND DATA
+	JR	Z,PPA_RUNCMD_READ
+	CP	$F0			; DEVICE WANTS TO BE DONE
+	JR	Z,PPA_RUNCMD_END
+	JR	PPA_CMD_IOERR
+;
+PPA_RUNCMD_WRITE:
+	LD	DE,(PPA_DSKBUF)		; XFER BUFFER
+	LD	HL,(PPA_XFRLEN)		; XFER LENGTH
+	CALL	PPA_PUTDATA		; SEND DATA NOW
+	JR	PPA_RUNCMD_PHASE	; BACK TO DISPATCH
+;
+PPA_RUNCMD_READ:
+	;CALL	PPA_NEGOTIATE		; NEGOTIATE FOR READ
+	;CALL	PPA_WAIT		; WAIT TILL READY
+	LD	DE,(PPA_DSKBUF)		; XFER BUFFER
+	LD	HL,(PPA_XFRLEN)		; XFER LENGTH
+	CALL	PPA_GETDATA		; GET THE DATA NOW
+	;CALL	PPA_ENDREAD		; TERMINATE THE READ
+	JR	PPA_RUNCMD_PHASE	; BACK TO DISPATCH
+;
+PPA_RUNCMD_END:
+	;CALL	PPA_NEGOTIATE		; NEGOTIATE FOR READ (STATUS)
+	;CALL	PPA_WAIT		; WAIT TILL READY
+	CALL	PPA_GETSTATUS		; READ STATUS BYTES
+	;CALL	PPA_ENDREAD		; TERMINATE THE READ
+	CALL	PPA_DISCONNECT		; PARALLEL PORT BUS DISCONNECT
+	XOR	A			; SIGNAL SUCCESS
+	RET
+;
+PPA_CMD_IOERR:
+	LD	A,PPA_STIOERR		; ERROR VALUE TO A
+	JR	PPA_CMD_ERR		; CONTINUE
+;
+PPA_CMD_TIMEOUT:
+	LD	A,PPA_STTO		; ERROR VALUE TO A
+	JR	PPA_CMD_ERR		; CONTINUE
+;
+PPA_CMD_ERR:
+	LD	SP,(PPA_CMDSTK)		; UNWIND STACK
+	PUSH	AF			; SAVE STATUS
+	;CALL	PPA_RESETPULSE		; CLEAN UP THE MESS???
+	LD	DE,62			; DELAY AFTER RESET PULSE
+	CALL	VDELAY
+	CALL	PPA_DISCONNECT		; PARALLEL PORT BUS DISCONNECT
+	LD	DE,62			; DELAY AFTER DISCONNECT
+	CALL	VDELAY
+	POP	AF			; RECOVER STATUS
 	JP	PPA_ERR			; NOW DO STANDARD ERR PROCESSING
 ;
 ; ERRORS SHOULD GENERALLY NOT CAUSE SCSI PROCESSING TO FAIL.  IF A
@@ -656,7 +1048,8 @@ PPA_CHKCMD1:
 ;
 	; REQ SENSE CMD COMPLETED
 #IF (PPATRACE >= 3)
-	LD	A,16
+	PRTS("\r\nSENSE:$")
+	LD	A,$19
 	LD	DE,HB_WRKBUF
 	CALL	Z,PRTHEXBUF
 #ENDIF
@@ -693,7 +1086,86 @@ PPA_INITDEV:
 	OUT	(C),A			; DO IT
 	CALL	DELAY			; SHORT DELAY FOR BUS SETTLE
 ;
-	JP	PPA_NOTSUP
+	; BUS RESET
+	CALL	PPA_CONNECT
+	CALL	PPA_RESETPULSE
+	LD	DE,62			; 1000 US
+	CALL	VDELAY
+	CALL	PPA_DISCONNECT
+	LD	DE,62			; 1000 US
+	CALL	VDELAY
+;
+	; INITIALLY, THE DEVICE MAY REQUIRE MULTIPLE REQUEST SENSE
+	; COMMANDS BEFORE IT WILL ACCEPT I/O COMMANDS.  THIS IS DUE
+	; TO THINGS LIKE BUS RESET NOTIFICATION, MEDIA CHANGE, ETC.
+	; HERE, WE RUN A FEW REQUEST SENSE COMMANDS.  AS SOON AS ONE
+	; INDICATES NO ERRORS, WE CAN CONTINUE.
+	LD	B,4			; TRY UP TO 4 TIMES
+PPA_INITDEV1:
+	PUSH	BC			; SAVE LOOP COUNTER
+;
+	; REQUEST SENSE COMMAND
+	LD	DE,HB_WRKBUF		; BUFFER FOR SENSE DATA
+	LD	BC,0			; READ WHATEVER IS SENT
+	LD	HL,PPA_CMD_SENSE	; POINT TO CMD BUFFER
+	CALL	PPA_RUNCMD		; RUN THE SCSI ENGINE
+	JR	NZ,PPA_INITDEV2		; CMD PROC ERROR
+;
+#IF (PPATRACE >= 3)
+	PRTS("\r\nSENSE:$")
+	LD	A,$19
+	LD	DE,HB_WRKBUF
+	CALL	PRTHEXBUF
+#ENDIF
+;
+	; CHECK SENSE KEY
+	LD	A,(HB_WRKBUF + 2)	; GET SENSE KEY
+	OR	A			; SET FLAGS
+;
+PPA_INITDEV2:
+	POP	BC			; RESTORE LOOP COUNTER
+	JR	Z,PPA_INITDEV3		; IF NO ERROR, MOVE ON
+	DJNZ	PPA_INITDEV1		; TRY UNTIL COUNTER EXHAUSTED
+	JP	PPA_IOERR		; BAIL OUT WITH ERROR
+;
+PPA_INITDEV3:
+	; READ & RECORD DEVICE CAPACITY
+	LD	DE,HB_WRKBUF		; BUFFER TO CAPACITY RESPONSE
+	LD	BC,0			; READ WHATEVER IS SENT
+	LD	HL,PPA_CMD_RDCAP	; POINT TO READ CAPACITY CMD
+	CALL	PPA_RUNCMD		; RUN THE SCSI ENGINE
+	CALL	Z,PPA_CHKCMD		; CHECK AND RECORD ANY ERRORS
+	RET	NZ			; BAIL OUT ON ERROR
+;
+#IF (PPATRACE >= 3)
+	PRTS("\r\nRDCAP:$")
+	LD	A,8
+	LD	DE,HB_WRKBUF
+	CALL	PRTHEXBUF
+#ENDIF
+;
+	; CAPACITY IS RETURNED IN A 4 BYTE, BIG ENDIAN FIELD AND
+	; INDICATES THE LAST LBA VALUE.  WE NEED TO CONVERT THIS TO
+	; LITTLE ENDIAN AND INCREMENT THE VALUE TO MAKE IT A CAPACITY
+	; COUNT INSTEAD OF A LAST LBA VALUE.
+	LD	A,PPA_MEDCAP		; OFFSET IN CFG FOR CAPACITY
+	CALL	LDHLIYA			; POINTER TO HL
+	PUSH	HL			; SAVE IT
+	LD	HL,HB_WRKBUF		; POINT TO VALUE IN CMD RESULT
+	CALL	LD32			; LOAD IT TO DE:HL
+	LD	A,L			; FLIP BYTES
+	LD	L,D			; ... BIG ENDIAN
+	LD	D,A			; ... TO LITTLE ENDIAN
+	LD	A,H
+	LD	H,E
+	LD	E,A
+	CALL	INC32			; INCREMENT TO FINAL VALUE
+	POP	BC			; RECOVER SAVE LOCATION
+	CALL	ST32			; STORE VALUE
+;
+	XOR	A			; SIGNAL SUCCESS
+	LD	(IY+PPA_STAT),A		; RECORD IT
+	RET
 ;
 ;=============================================================================
 ; ERROR HANDLING AND DIAGNOSTICS
@@ -726,7 +1198,7 @@ PPA_ERR:
 	LD	(IY+PPA_STAT),A		; SAVE NEW STATUS
 ;
 PPA_ERR2:
-#IF (PPATRACE >= 1)
+#IF (PPATRACE >= 2)
 	CALL	PPA_PRTSTAT
 #ENDIF
 	OR	A			; SET FLAGS

Source/HBIOS/syq.asm

@@ -9,7 +9,7 @@
 ; INTENDED TO CO-EXIST WITH LPT DRIVER.
 ;
 ; CREATED BY WAYNE WARTHEN FOR ROMWBW HBIOS.
-; MUCH OF THE CODE IS DERIVED FROM FUZIX (ALAN COX).
+; MUCH OF THE CODE IS DERIVED FROM LINUX AND FUZIX (ALAN COX).
 ;
 ; 5/29/2023 WBW - INITIAL RELEASE
 ;
@@ -393,15 +393,17 @@ SYQ_WRITE:
 ;
 ;
 SYQ_IO:
-	LD	(SYQ_DSKBUF),HL		; SAVE DISK BUFFER ADDRESS
-	LD	A,B			; XFR MODE TO ACCUM
-	LD	(SYQ_XFRMODE),A		; AND SAVE IT FOR CMD
 ;
 	PUSH	BC			; SAVE MODE/COMMAND
+	PUSH	HL			; SAVE DISK BUF PTR
 	CALL	SYQ_CHKERR		; CHECK FOR ERR STATUS AND RESET IF SO
+	POP	HL			; RECOVER DISK BUF PTR
 	POP	BC			; RECOVER MODE/COMMAND
 	JR	NZ,SYQ_IO1		; BAIL OUT ON ERROR
 ;
+	LD	A,B			; XFR MODE TO ACCUM
+	LD	(SYQ_XFRMODE),A		; AND SAVE IT FOR CMD
+	LD	(SYQ_DSKBUF),HL		; SAVE DISK BUFFER ADDRESS
 	LD	A,SYQ_LBA		; LBA OFFSET IN CONFIG
 	CALL	LDHLIYA			; POINT TO LBA DWORD
 	CALL	LD32			; SET DE:HL TO LBA

Source/ver.inc

@@ -2,7 +2,7 @@
 #DEFINE	RMN	3
 #DEFINE	RUP	0
 #DEFINE	RTP	0
-#DEFINE BIOSVER	"3.3.0-dev.18"
+#DEFINE BIOSVER	"3.3.0-dev.20"
 #define rmj	RMJ
 #define rmn	RMN
 #define rup	RUP

Source/ver.lib

@@ -3,5 +3,5 @@ rmn	equ	3
 rup	equ	0
 rtp	equ	0
 biosver	macro
-	db	"3.3.0-dev.18"
+	db	"3.3.0-dev.20"
 	endm