;******************************************************************************
;				SETBOOT v. 1.0
;				--------------
;
;	This program is used to patch the disk resident autostart command in
; single and double density Osborne 1 computers.  This program will prompt the
; user for the disk drive on which the command is to be placed, the command
; string, and the conditions under which the command should be used.  SETBOOT
; is as general as I can make it, and is only limited by the capabilities of
; the Osborne BIOS.
;
; Author: Noel J. Bergman
;
; (c) Copyright 1983, Noel J. Bergman
; ALL RIGHTS RESERVED
;
; This program may be freely distributed for personal use only.  Any use of
; of this program for commercial purposes requires prior written approval
; from the author.  Commercial purposes shall include distribution by any
; organization affiliated with Lifeboat Associates.  The address to write to
; for approval is:
;			Noel J. Bergman
;			8329 High School Road
;			Elkins Park, PA 19117
;------------------------------------------------------------------------------
;				Modification Log
;				------------ ---
;
; 04/01/83 - Original version.  Uses DPB to determine whether disk is single
;	     or double density.  Track, sector and sector offset locations are
;	     hardcoded. BIOS versions 1.4x are known to work.
;******************************************************************************

;*-	Autostart Information Equates

SCODE	EQU	5		; SINGLE DENSITY disk type code
STRK	EQU	2		; SINGLE DENSITY track location
SSEC	EQU	3		; SINGLE DENSITY sector location
SOFF	EQU	1Ch		; SINGLE DENSITY byte offset
SMAX	EQU	7		; SINGLE DENSITY maximum command length

DCODE	EQU	0Ch		; DOUBLE DENSITY disk type code
DTRK	EQU	1		; DOUBLE DENSITY track location
DSEC	EQU	5		; DOUBLE DENSITY sector location
DOFF	EQU	1Ch		; DOUBLE DENSITY byte offset
DMAX	EQU	7		; DOUBLE DENSITY maximum command length

;*-	CP/M 2.2 BDOS and BIOS Entry Point Equates

BDOS	EQU	0005h		; BDOS entry point
COS	EQU	09h		; BDOS Console Output String
CIL	EQU	0Ah		; BDOS Console Input Line
RSTDRV	EQU	25h		; BDOS Reset Selected Drive(s)
SELDRV	EQU	0Eh		; BDOS Select Drive
DSKPRM	EQU	1Fh		; BDOS Get Disk Parameters

BIOSE	EQU	0001h		; BIOS pointer to jump table
SELDSK	EQU	18h		; BIOS Select disk (to get XLAT table address)
SETTRK	EQU	1Bh		; BIOS Set Track
SETSEC	EQU	1Eh		; BIOS Set Sector
SETDMA	EQU	21h		; BIOS Set DMA
READ	EQU	24h		; BIOS Read Sector
WRITE	EQU	27h		; BIOS Write Sector
SECTRN	EQU	2Dh		; BIOS Sector Translation

;*-	BIOS related utility macro

BIOS	MACRO	FUNCTION	; Macro to make BIOS service calls.
	LOCAL	Lx		; Force assembler to generate unique labeling.
	LD  	HL,(BIOSE)	; HL ::= address of BIOS warm boot entry. 

	IF	FUNCTION EQ SECTRN
	PUSH	DE		; DE contains pointer to XLAT table for SECTRN
	ENDIF

	LD	DE,FUNCTION	; DE ::= offset from BIOS warm boot to desired
				; entry point.
	ADD	HL,DE		; HL ::= address of desired BIOS entry point.

	IF	FUNCTION EQ SECTRN
	POP	DE		; Restore pointer to XLAT table
	ENDIF

	LD	(Lx+1),HL	; fill in the address field of the BIOS call.
Lx:	CALL	0000h		; the relocatable call instruction.
	ENDM

;*-	Miscellaneous Equates

CR	EQU	0Dh		; Carriage Return
LF	EQU	0Ah		; Line Feed

;******************************************************************************
;	Print a welcome message.
;
	.Z80
	ASEG
	ORG	100h

START:	LD	(STACK),SP	; STACK ::= Old SP
	LD	SP,STACK	; SP ==> STACK

	CALL	QUERY1		; Print startup message
	D  	CR,LF,'SETBOOÔ [1.0NjB¬ Lasô Modifieä 4/01/83]'
	DB	CR,LF
	DB	CR,LF,'Thió versioî oæ SETBOOÔ wilì worë witè botè singlå'
	DB	CR,LF,'anä doublå densitù Osbornå disks®   Remembeò  thaô'
	DB	CR,LF,'iæ  yoõ wanô tï modifù á doublå densitù disk¬  yoõ'
	DB	CR,LF,'musô  bå usinç á doublå densitù machine¬  anä  yoõ'
	DB	CR,LF,'musô  havå  "booted¢ thå computeò  witè  á  doublå'
	DB	CR,LF,'densitù disë iî drivå A®  Makå surå thaô eacè disë'
	DB	CR,LF,'tï  bå modifieä haó á copù oæ CP/Í witè BIOÓ 1.4x®'
	DB	CR,LF,'Thå  prograí wilì prompô yoõ foò eacè  actioî  yoõ'
	DB	CR,LF,'musô  perforí  anä eacè questioî yoõ musô  answer®'
	DB	CR,LF,'Everù attempô haó beeî madå tï makå thió operatioî'
	DB	CR,LF,'painless¬ sï remembeò thå keù tï computing:'
	DB	CR,LF
	DB	CR,LF,'	NO MATTER WHAT GOES WRONG, DON''T PANIC.'
	DB	CR,LF
	DB	CR,LF
	DB	CR,LF
	DB	CR,LF
	DB	CR,LF
	DB	CR,LF
	DB	CR,LF
	DB	CR,LF,'Hit any key when ready to continue:','$'

;******************************************************************************
;	This is the beginning of the main program loop.  Here we tell him to
; put the disk that he wants to setup into drive B, and then we wait for him
; to do so.
;	After he has placed the disk into drive B, we must check to see
; whether we are dealing with single or double demsity by checking the sector
; size in the DPB.  Once that is known, the location information for that type
; of disk is setup, and the correct sector is read into the buffer.
;
DODISK:	CALL	QUERY1		; Prompt user for disk change.
	DB	CR,LF
	DB	CR,LF,'Pleaså placå thå disë tï bå modifieä iî drivå  B§ 
	D 	CR,LF,'anä then presó any key.','$'

;*- issue a drive reset so that BDOS will login new disk.
 
	LD	DE,0002h	; DE ::= drive map (only B is set)
	LD	C,RSTDRV	; C  ::= BDOS code for reset selected drive(s)
	CALL	BDOS

;*- select the B: drive
 
	LD	E,01h		; E  ::= drive code for B:
	LD	C,SELDRV	; C  ::= BDOS code for select drive
	CALL	BDOS

;*- let's take a look at the dpb and see what density disk it defines

	LD	C,DSKPRM	; C  ::= BDOS code for Get Disk Parameters
	CALL	BDOS		; HL ==> DPB for B:
	DEC	HL		; HL ==> Osborne code for this disk type
	LD	A,(HL)		; A  ::= disk type

	CP	SCODE		; Is it a single density disk?
	JP	NZ,DCHK		; No, see if it is double density

;*- fall through to setup for a single density disk.

	LD	HL,STBL		; HL ==> single density information table
	LD	BC,DTBL-STBL	; BC ::= number of bytes to copy
	LD	DE,TRACK	; DE ==> information table for this disk
	LDIR			; Copy the table
	JP	READIT		; get the sector with the autostart command

;*- see if it is double density.

DCHK:	CP	DCODE		; Is it a double density disk?
	JP	NZ,BADDSK	; No, it is neither single nor double

;*- fall through to setup for a double density disk.

	LD	HL,DTBL		; HL ==> double density information table
	LD	BC,TRACK-DTBL	; BC ::= number of bytes to copy
	LD	DE,TRACK	; DE ==> information table for this disk
	LDIR			; Copy the table
	JP	READIT		; get the sector with the autostart command

;*- tell the jerk that the disk is no good.

BADDSK:	CALL	ILPRT
	DB	CR,LF
	DB	CR,LF,'Thió ió noô  aî Osbornå Singlå oò  Doublå  densitù'�
	DB	CR,LF,'disk.  You are welcome to try again,  but you must'
	DB	CR,LF,'use only Osborne format disks.','$'
	JP	DONE

;******************************************************************************
;	Having figured out what type of disk we are dealing with, and having
; setup a table of information about it, it is now time to read the sector
; containing the autoboot information.  If the length of the autoboot command
; is an E5h, we assume that this disk does not have a copy of CP/M on it.
;
READIT:	LD	BC,(TRACK)	; BC  ::= track number
	BIOS	SETTRK		; Call BIOS to set the track

	LD	C,1		; C  ::= code for drive B:
	BIOS	SELDSK		; Select disk via BIOS so we can find XLAT
	LD	E,(HL)		; E  ::= byte offset of XLAT table
	INC	HL		; HL ==> page address of XLAT table
	LD	D,(HL)		; DE ==> XLAT table

	LD	BC,(SECTOR)	; C  ::= sector number

	LD	A,D		; A  ::= page address of XLAT table
	OR	E		; A  = 0 if no XLAT table used
	JP	Z,NXLAT		; so skip the translation

	BIOS	SECTRN		; Call BIOS to get physical sector number
	LD	B,H
	LD	C,L		; BC ::= physical sector number

NXLAT:	BIOS	SETSEC		; Call BIOS to set the sector number
	LD	BC,SECBUF	; BC ==> sector storage area
	BIOS	SETDMA		; Tell BIOS where to load sector

	BIOS	READ		; Call BIOS to read the sector
	OR	A		; ((A = 0) ==> good read)
	CALL	NZ,SYSERR	; no, so abort.

	LD	A,(SECBUF+SOFF+1)	; A ::= byte to be tested
	CP	0E5h		; Length = format code?
	JP	NZ,FOUND	; No, there is an autostart command

	CALL	ILPRT		; Tell him that there must be CP/M on the disk
	DB	CR,LF
	DB	CR,LF,'Thå disë yoõ havå selecteä doeó noô havå á copù oæ'
	DB	CR,LF,'CP/Í oî it®   Iæ yoõ wisè tï instalì aî  autostarô'
	DB	CR,LF,'commanä  oî  thå disk¬  yoõ musô firsô follo÷  thå'
	DB	CR,LF,'directionó  iî thå Osbornå manuaì foò  placinç  aî'
	DB	CR,LF,'operatinç systeí oî thå disk®','$'

	JP	DONE		; and prepare to exit.

;******************************************************************************
;	At this point SECBUF contains a valid autostart sector.  We check to
; see if there is an autostart command installed, and if there is we tell him
; what it is and when it is executed.
; 
FOUND:	LD	A,(SECBUF+SOFF)	; A  ::= autostart conditions
	CP	0		; (A =0) ==> ignore autostart
	JP	NZ,SAUTO	; No, there is an autostart command installed

	CALL	ILPRT		; Show the user that there is no autostart
	DB	CR,LF
	DB	CR,LF,'There is no autostart command on this disk.','$'

	JP	CHANGE		; See if he wants to change things.

;*-	There is an autostart command so show it to him

SAUTO:	LD	A,' '		; Prepare to clear space for name of command
	LD	(ANAME),A	; Clear first byte
	LD	HL,ANAME	; Copy from first byte
	LD	DE,ANAME+1	; to rest of command via propogation of spaces
	LD	BC,ENAME-ANAME-1; Number of spaces to clear
	LDIR

	LD	HL,SECBUF+SOFF+2; HL ==> autostart command
	LD	DE,ANAME	; DE ==> place in message for name of command
	LD	BC,(SECBUF+SOFF+1)	; BC ::= length of autostart command
	LD	B,0		; Length is only one byte
	LDIR			; Put the command into the message

	CALL	ILPRT		; Show user the current autostart command
	DB	CR,LF
	DB	CR,LF,'Thå currenô autostarô commanä isº  "'
ANAME:	DB	'       '	; Space for name of command
ENAME:	DB	'"®  Thå'
	DB	CR,LF,'autostart conditions are:'
	DB	CR,LF,'$'

;*-	See it it runs at cold boot time (condtion code <> 2)

	LD	A,(SECBUF+SOFF)	; A  ::= autostart conditions
	CP	2		; (A <> 2) ==> autostart at cold boot
	JP	Z,SWARM		; Skip this message  

	CALL	ILPRT		; Show cold boot condition
	DB	CR,LF,'	* Perform command upon cold boot','$'

;*- 	See if it runs at warm boot time (condition code <> 1)
 
SWARM:	LD	A,(SECBUF+SOFF)	; A  ::= autostart conditions
	CP	1		; (A <> 1) ==> autostart at warm boot
	JP	Z,CHANGE	; Skip this message

	CALL	ILPRT		; Show warm boot condition
	DB	CR,LF,'	* Perform command upon warm boot','$'

;******************************************************************************
;	Now we want to find out what changes he wants to make.
; 
CHANGE:	CALL	QUERY1		; See if he wishes to change the situation
	DB	CR,LF
	D 	CR,LF,'Dï yoõ wisè tï changå thió setup¿ (Y/N):','$'

	LD	A,(CIBUF+2)	; A  ::= user response
	AND	5Fh		; capitalize the response
	CP	'Y'
	JP	Z,CHANG2	; Yes, let's change it. 
	CP	'N'
	JP	Z,DONE		; No, leave it is it is now.
	JP	CHANGE		; Accept only yes or no responses

;*-	Maybe he wants to remove the autostart command entirely

CHANG2:	CALL	QUERY1		; See if he wants to remove the autostart
	DB	CR,LF
	DB	CR,LF,'Do you want this disk to autostart? (Y/N):','$'

	LD	A,(CIBUF+2)	; A  ::= user response
	AND	5Fh		; capitalize the response
	CP	'Y'
	JP	Z,GETA		; Yes, some get the command
	CP	'N'
	JP	NZ,CHANG2	; Accept only yes or no responses
	XOR	A		; clear A
	LD	(SECBUF+SOFF),A	; Disable autostart
	LD	BC,1		; Force BIOS to perfrom immdediate write
	BIOS	WRITE		; Write the sector to disk
	OR	A		; Check for write errors
	CALL	NZ,SYSERR	; oh, shit -- print error message
	JP	DONE		; and prepare to terminate

GETA:	CALL	QUERY7		; Get the new autostart command
	DB	CR,LF
	DB	CR,LF,'Pleaså enteò thå ne÷ autostarô command® Therå ió á'
	DB	CR,LF,'limiô oæ no more than seveî (7© characters:','$'

	LD	HL,CIBUF+1	; HL ==> length of new command and command
	LD	BC,(CIBUF+1)	; BC ::= length of new command
	LD	B,0		; Length is only one byte
	INC	BC		; Update Byte Count to include command length
	LD	DE,SECBUF+SOFF+1; DE ==> disk resident autostart command buffer
	LDIR			; move it

GETC:	CALL	QUERY1		; Get the new autostart conditions
	DB	CR,LF
	DB	CR,LF,'Undeò whaô conditionó ió thió autostarô commanä tï'
	DB	CR,LF,'bå executed¿ Pleaså makå youò selectioî bù chosinç'
	DB	CR,LF,'the number next to your choice.'
	DB	CR,LF
	DB	CR,LF,'	1. Perform command upon cold boot'
	DB	CR,LF,'	2. Perform command upon warm boot'
	DB	CR,LF,'	3® Perforí commanä upoî eitheò warí booô'
	DB	CR,LF,'	   or cold boot.'
	DB	CR,LF
	DB	CR,LF,'Selection? (1,2 or 3):','$'

	LD	A,(CIBUF+2)	; A  ::= user response
	SUB	'1'		; A  ::= A - ord('1'), valid A in 0..2
	JP	C,GETC		; (A < '1') ==> bad response
	SUB	3		; A  ::= A - 3, valid A in -3..-1
	JP	NC,GETC		; (A > '3') ==> bad response
	ADD	A,4		; bring A back to 1..3
	LD	(SECBUF+SOFF),A	; install new condition code
	LD	BC,1		; Force BIOS to perfrom immdediate write
	BIOS	WRITE		; Write the sector to disk
	OR	A		; Check for write errors
	CALL	NZ,SYSERR	; oh, shit -- print error message

DONE:	CALL	QUERY1		; See if he wants to do any more disks.
	DB	CR,LF
	DB	CR,LF,'Do you want to do any more disks now? (Y/N):','$'
	LD	A,(CIBUF+2)	; A  ::= user response
	AND	5Fh		; capitalize the response
	CP	'Y'
	JP	Z,DODISK	; do another disk
	CP	'N'
	JP	NZ,DONE		; accept only yes or no response
	JP	EXIT

;******************************************************************************
;	This routine assumes that the top of the stack is a pointer to a string
; to be displayed via the BDOS console output string function.  The catch is
; that the caller wants this routine to return to the address immediately
; following the message.  This function provides us with an in-line print
; facility.
;
ILPRTº	POÐ	HÌ		» HÌ ==¾ string
	PUSH	HL		; TOS ==> string
	LD	A,'$'		; A  ::= end marker
	LD	BC,2048 	; Allow maximum string length of 2k (safety)
	CPIR			; Search for '$' end marker
	CALL	NZ,SYSERR	; SYSTEM ERROR - we didn't find an end marker
	POP	DE		; DE ==> string
	PUSH	HL		; TOS ::= caller's return address
	LD	C,COS		; C  ::= BDOS code for Console Output String
	CALL	BDOS		; Output the string
	RET			; Return to caller

;******************************************************************************
;	These two routines are used to prompt the user for some input, and
; to read in the user's response.  Both routines use the BDOS Console Input
; Line (CIL) function to get their input, and so they are compatible with
; the SUBMIT facility.  They only differ in the number of characters that
; the BDOS will accept before returning to the program.
;
QUERY1:	LD	A,1
	LD	(CIBUF),A	; Set maximum length of console input to 1
	JP	QUERY

QUERY7:	LD	A,7
	LD	(CIBUF),A	; Set maximum length of console input to 7

QUERY:	POÐ	HÌ		» HÌ ==¾ string
	PUSH	HL		; TOS ==> string
	LD	A,'$'		; A  ::= end marker
	LD	BC,2048 	; Allow maximum string length of 2k (safety)
	CPIR			; Search for '$' end marker
	CALL	NZ,SYSERR	; SYSTEM ERROR - we didn't find an end marker
	POP	DE		; DE ==> string
	PUSH	HL		; TOS ::= caller's return address
	LD	C,COS		; C  ::= BDOS code for Console Output String
	CALL	BDOS		; Output the string
	LD	C,CIL		; C  ::= BDOS code for Console Input Line
	LD	DE,CIBUF	; DE ==> console input buffer
	CALL	BDOS		; Get user input 

	RET

;******************************************************************************
;	These two routines, SYSERR and EXIT, get control when it is time to
; return to CP/M.  SYSERR is the error exit routine and EXIT is the normal
; exit routine.  The difference is that SYSERR prints an error message before
; terminating.
;
SYSERR:	POP	HL		; HL ==> instruction following CALL SYSERR
	LD	DE,-3		; CALL instruction is 3 bytes long
	ADD	HL,DE		; HL ==> CALL SYSERR instruction
	LD	DE,ERRADR	; DE ==> place to put printable hex number
	LD	C,H		; C  ::= page address of call instruction
	CALL	PUTHEX		; Put 2 hex digits at (DE) and (DE+1)
	LD	C,L		; C  ::= page offset of call instruction
	CALL	PUTHEX		; Put 2 hex digits at (DE) and (DE+1)

	CALL	ILPRT		; Print error message
	DB	CR,LF
	DB	CR,LF,'%ERROR - SYSERR called from '
ERRADR:	DB	'0000'
	DB	'h.   Please record'
	DB	CR,LF,'this information  and give  it to  the appropriate'
	DB	CR,LF,'person(s).  If you cannot get help from some other'
	DB	CR,LF,'source, you may obtain it by writing (NOT calling)'
	DB	CR,LF,'to the address below:'
	DB	CR,LF
	DB	CR,LF,'	Noel J. Bergman'
	DB	CR,LF,'	8329 High School Road'
	DB	CR,LF,'	Elkins Park, PA 19117'
	DB	CR,LF
	DB	CR,LF,'Be sure to include  the SETBOOT version number and'
	DB	CR,LF,'last date modified,  the address SYSERR was called'
	DB	CR,LF,'from,  the BIOS and ROM revision  numbers of  your'
	DB	CR,LF,'Osborne, the density of the disks you were working'
	DB	CR,LF,'with in both  drives,  and a  transcription of the'
	DB	CR,LF,'entire dialog between you and SETBOOT. Please note'
	DB	CR,LF,'that this error does not necessarily mean that you'
	DB	CR,LF,'have a problem with your computer.   If you do not'
	DB	CR,LF,'have other  problems with  your Osborne,  you need'
	DB	CR,LF,'not be overly concered about this error.','$'

	JP	EXIT

;*- these are two utility routines for Binary to Hex conversion

PUTHEX:	LD	A,C		; A  ::= byte to be converted
	RRA
	RRA
	RRA
	RRA
	CALL	PUT1		; do high order character
	LD	A,C		; and low order character

PUT1:	AND	0Fh		; drop top nibble
	ADD	A,90h
	DAA
	ADC	A,40h
	DAA
	LD	(DE),A		; put printable digit in string
	INC	DE		; point to next position
	RET

;*- Restore CP/M's stack and return to CP/M

EXIT:	LD	SP,(STACK)	; Restore CP/M's stack
	RET			; and return from whence we came

;******************************************************************************
;			Data Storage Areas
;
; The general format of the sector we are dealing with is:
;
;	0_____1B_1C_1D_1E_____24_25________80_
;	|	| A| B|	   C	|	     |
;	--------------------------------------
;
;	A == Autostart conditions
;	B == Length of autostart command
;	C == Autostart command

SECBUF:	DS	128		; Storage for the sector
CIBUF:	DS	9		; Console Input BUFfer
	DS	128		; Local stack space
STACK:	DS	2		; + space for CP/M's stack pointer

;*-	Location Information 

STBL:	DW	STRK,SSEC,SOFF	; SINGLE DENSITY information table
DTBL:	DW	DTRK,DSEC,DOFF	; DOUBLE DENSITY information table

TRACK:	DS	2		; storage for track number to be used
SECTOR:	DS	2		; storage for sector number to be used
OFFSET:	DS	2		; storage for offset to be used
	END