RomWBW/Source/BPBIOS/bpbio-dx.z80

;*****************************************************************************
; BP-BIOS.   Banked, Portable BIOS.
;	Copyright (c) 1989-93 by Cameron W. Cotrill and Harold F. Bower
;
;  This program is free software; you can redistribute it and/or modify
;  it under the terms of the GNU General Public License as published by
;  the Free Software Foundation; either version 2 of the License, or (at
;  your option) any later version.
;
;  This program is distributed in the hope that it will be useful, but
;  WITHOUT ANY WARRANTY; without even the implied warranty of
;  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
;  General Public License for more details.
;
;  You should have received a copy of the GNU General Public License
;  along with this program; if not, write to the Free Software
;  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
;
;----------------------------------------------------------------------------
;    This BIOS is broken into modules that allow it to be ported across a
; wide variety of Z80 compatible systems.  All hardware specific drivers
; are isolated to separate modules.  All hardware independent modules (such
; as deblocking and IO redirection) are similarly broken out.
;
; The BP BIOS supports IOBYTE, but in a unique manner.  Four physical devices
; are defined - COM1, COM2, PIO, and NULL.  These are assigned to the CON,
; AUXIN, AUXOUT, and LST logical devices by the I/O byte.  The NULL device is
; a bit bucket for output, and returns nulls for input.
;
; IOBYTE DESCRIPTION:	LIST   AUXOUT   AUXIN	CON
;	D7->D0		 XX	 XX	 XX	 XX
;
; XX:	00=COM1    01=COM2    10=PIO	11=NULL
;
;+++++++++++++++++ D-X Designs Pty Ltd P112 Version ++++++++++++++++++
;
; This configuration of the B/P Bios is for Dave Brooks' Project 112 Single
; board computer.  Multifunction chips on the board provide the services
; needed by a CP/M BIOS.  The primary chips and the functions provided are:
;
;   Zilog Z80182	Z180 Core CPU, MMU, DMA
;	ESCC #1		COM1 Serial Port w/handshake signals, RS-232
;	ESCC #2		 (available on header, coded as expansion)
;	ASCI0, ASCI1	 (Serial async, available on header, expansion)
;	CTC1		Optional 'heartbeat' clock, GP timer
;
;   SMC FDC37C665	Enhanced 765-derivative Floppy Disk Controller
;			COM2 - 16550-compatible Serial, RS-232
;			PAR1 - Centronics Parallel port (Printer)
;
;   Dallas DS-1202	Primary Realtime clock
;			Non-volatile battery-backed RAM (config data)
;
;   28F256 Flash ROM	Boot code, device initialization
;			 (onboard programmable)
;   32/128/512 KB Static RAM
;
; Ver     Date        Revision Description
; ---   ---------   ------------------------
; 1.3   28 Aug 01 - Scrubbed for GPL Release.				HFB
; 1.2 - 30 Aug 97 - Expanded SCSI CDB length to 12 bytes for CDROM.	HFB
; 1.1 - 11 May 97 - Added IDE Hard Drive instead of Normal SCSI, updated
;		files to latest version.				HFB
; 1.0 - 13 Aug 96 - Initial Release for P112 from YASBEC release.	HFB
;*****************************************************************************

	NAME	BPBIO

FALSE	EQU	0
TRUE	EQU	NOT FALSE
NO	EQU	FALSE
YES	EQU	TRUE
				; << ******  SYSTEM SPECIFIC  ****** >>
				; <<  Insert DEF-xxxx.LIB definition >>
	INCLUDE	DEF-DX.LIB	; <<   file for your configuration.  >>

	CSEG
;.....
; Ascii Character Equates

ETX	EQU	03H		; End-of-Text
ACK	EQU	06H		; Acknowledge
BELL	EQU	07H		; Bell Character
CR	EQU	0DH
LF	EQU	0AH
XON	EQU	11H		; X-On  (Control-Q)
XOFF	EQU	13H		; X-Off (Control-S)
ESC	EQU	1BH

; Miscellaneous Equates

WRUAL	EQU	2		; DOS code for unallocated write

LOCKF	EQU	LOW [NOT AUTOSL] ;Lock flag for format default
ALONE	EQU	FALSE		; Boot code equate
	  IF  Z3
	MACLIB	Z3BASE		; Include ENV definitions
	  ENDIF
	PAGE
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
;  BIOS Entry Jump Table - This MUST be in Common Memory
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

	CSEG

BIOSJT:	JP	CBOOT		; 00 Cold Boot
	JP	WBOOT		; 01 Warm Boot
	JP	CONST		; 02 console input status	* (IOP+12)
	JP	CONIN		; 03 console input		* (IOP+15)
	JP	CONOUT		; 04 console output		* (IOP+18)
	JP	LIST		; 05 list output		* (IOP+21)
	JP	AUXOUT		; 06 aux out (punch)		* (IOP+24)
	JP	AUXIN		; 07 aux in (reader)		* (IOP+27)
	JP	HOME		; 08 seek track 0
	JP	SELDSK		; 09 select logical drive
	JP	SETTRK		; 10 select track
	JP	SETSEC		; 11 select sector
	JP	SETDMA		; 12 set dma address for disk xfer
	JP	READ		; 13 disk read
	JP	WRITE		; 14 disk write
	JP	LISTST		; 15 list output status		* (IOP+30)
	JP	SECTRN		; 16 logical -> physical sector xlate

; --- <<< End of CP/M 2.2 Vectors >>>

	JP	CONOST		; 17 Console Output Status
	JP	AUXIST		; 18 Aux Input Status
	JP	AUXOST		; 19 Aux Output Status
	JP	DEVTBL		; 20 CP/M 3 Device Table
	JP	DEVINI		; 21 Character Device Init (Near CP/M 3)
	JP	DRVTBL		; 22 DPH Pointer Table for A-P
	JP	0		; 23 RESERVED FOR MULTIO
	JP	FLUSH		; 24 Flush Deblocker
	JP	MOVE		; 25 Perform possible Inter-Bank Move
	  IF  CLOCK
	JP	TIME		; 26 Get/Set RTC (Zsdos params)
	  ELSE
	JP	ISTRUE		; 26..return 0FFH (No Clock) if No code
	  ENDIF		;clock
	JP	SELMEM		; 27 Select Alternate Memory Bank
	JP	SETBNK		; 28 Select DMA Memory bank
	JP	XMOVE		; 29 Set Source/Destination Banks for Move

; --- <<< End of CP/M 3 Vectors >>>

	JP	RETBIO		; 30 Return BIOS Addresses
	JP	DIRDIO		; 31 Direct Disk I/O
	JP	STFARC		; 32 Set Bank for FRJP and FRCALL
	JP	FRJP		; 33 Jump to (HL) in Alternate Bank
	JP	FRCLR		; 34 Clear Stack switcher from Alt Bank Jumps
				;	(used for error exits)
	JP	FRGETB		; 35 Load A,(HL) from Alternate Bank
	JP	FRGETW		; 36 Load DE,(HL) from Alternate Bank
	JP	FRPUTB		; 37 Load (HL),A to Alternate Bank
	JP	FRPUTW		; 38 Load (HL),DE to Alternate Bank
	JP	RETMEM		; 39 Return Current Active Memory Bank

CPR	EQU	BIOSJT-800H-0E00H
DOS	EQU	BIOSJT-0E00H

; End of BIOS Jump Table
	PAGE
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
;	Boot / Banked    Routine    Linkage
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

	  IF  BANKED
	COMMON	/BANK2/
ROMJT:
	   IF  INROM
	JP	INSYNC
INSYNC:	JP	BOOTER		; Cold start loader
	   ELSE
	JP	0		; Reserved
	JP	0
	   ENDIF		; Inrom
JDIRIO:	JP	DIRIO		; Low Level HDC/FDC Functions
JHDCIO:	JP	DIRIO		; Low Level HDC Functions (combined w/FDCIO)
JBREAD:	JP	BREAD		; BIOS Read
JBWRT:	JP	BWRT		; BIOS Write
JBSTRN:	JP	BSTRN		; BIOS Sectran
	   IF  INROM
	INCLUDE	BOOTROM.Z80	; Boot Routines
	   ENDIF		; Inrom
	  ENDIF			; Banked
	PAGE
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
;	  C o n f i g u r a t i o n    A r e a
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
				; << ****** HARDWARE SPECIFIC ****** >>
				; <<  Insert ICFG-xxx to initialize  >>
	INCLUDE	ICFG-DX.Z80	; <<    your computer's IO system    >>
	PAGE
				; << ****** Hardware Specific ****** >>
				; << Enter Low level Byte I/O driver >>
	INCLUDE	IIO-DX.Z80	; <<  routines in file IIO-xxxx.Z80  >>
	PAGE
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
;		Cold   Start   Code 
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

	DSEG
				; << ***** Hardware Specific ***** >>
				; << Insert the Cold boot routines >>
	INCLUDE	CBOOT-DX.Z80	; <<     in file CBOOT-xx.Z80      >>

; Deblocking Buffer Allocation

	  IF  [BANKED OR INROM]
	COMMON	/B2RAM/
	   IF  INROM
HSTBUF:	DEFS	INITCS		; Use a 1k buffer w/below
	   ELSE
HSTBUF	EQU	CBOOT0		; Use CBOOT0 code for part of buffer w/below
	   ENDIF	;inrom
	  ELSE
	DSEG
HSTBUF	EQU	CBOOT
	  ENDIF		;not banked
	DEFS	1024-(INITCS)	; Use a 1 k buffer

HSTSIZ	EQU	HSTBUF+1024	; Added label for Hard Drive ext. interface
	PAGE
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
;		Disk   Data   Structures
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

MXFDIR	EQU	255		; Max number of dir entries-1 for floppy

MXFALC	EQU	880		; If High Density or 8" drives can be handled,
				; set this for 880 (1.76 MB), otherwise the
				; value can be reduced to 400 (800 KB), the
				; maximum for 80 track, Double-Sided formats.
	CSEG
	  IF  BANKED
	COMMON  /BANK2/
	  ENDIF
DPB:				; Marker for DPB start
	.XLIST			; Don't print these due to size
	  IF  AUTOSL
	INCLUDE DPB.LIB		; Default selection of common DD formats
	   IF  FLOPYH
	INCLUDE	DPB-H.LIB	; If "High-Density" Disk formats desired,
	   ENDIF
	   IF  FLOPY8
	INCLUDE	DPB-8.LIB	; If 8" or HD Floppy Disks can be handled,
	   ENDIF		;  add default Autoselect DPB's
	   IF  MORDPB
	INCLUDE	DPB2.LIB	; Additional assignable DPB's (4+4 unused)
	   ENDIF	;mordpb

	  ELSE		;Not autosl
	INCLUDE	DPBRAM.LIB	; RAM-based DPB's, 1 per physical Format
	  ENDIF

NRDPB	EQU	[$-DPB]/DPBSIZ	; Calc number of DPB's

	CSEG			; Hard & Ramdisk DPBs and DPHs go in Code Seg
	.xlist
	  IF  HARDDSK
				; << ****** Hardware Specific ****** >>
				; <<  Insert DPB Info for Hard Disk  >>
	INCLUDE	DPBHD-DX.LIB	; <<     Drives as DPBHD-xx.LIB      >>
	  ENDIF
	.list
	  IF  RAMDSK
				; << ****** Hardware Specific ****** >>
				; <<  Insert DPB Info for RAM Disk   >>
	INCLUDE	DPBM-DX.LIB	; <<     in file DPBM-xxx.LIB        >>
	  ENDIF
	PAGE
	INCLUDE	DPH.LIB		; Disk parameter headers
	.xlist
	  IF  HARDDSK
	INCLUDE	DPHHD.LIB	; Insert DPH Info for Hard Disk Partitions
	  ENDIF
	.list
	  IF  RAMDSK
	INCLUDE	DPHM.LIB	; Insert DPH Info for RAM Disk
	  ENDIF
	.LIST
	PAGE
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
;     Disk   Driver   Low - Level   Function   Links
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
;::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
; Direct  Disk  I / O
;  Call with: Function Number in C, Driver number in B,
;	      Args in A, DE, HL
;::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
	CSEG
DIRDIO:
	  IF  BANKED
	CALL	BIOSTK
	CALL	GOSYSB		; Bank in the system bank
	JP	JDIRIO		; And jump to Banked-BIOS function

	COMMON	/BANK2/
	  ENDIF

DIRIO:	PUSH	HL		; Save user's HL
	PUSH	AF		; ..and A reg for range checks
	LD	A,B
	CP	MAXDDA		; Legal Driver #?
	JR	NC,DIRIOX	; ..jump Error Exit if Not
	PUSH	BC
	LD	HL,DDIOTB
	LD	C,B		; Driver number
	LD	B,0
	ADD	HL,BC
	ADD	HL,BC		; Index into table
	ADD	HL,BC
	LD	A,(HL)		; Max call number
	INC	HL
	LD	C,(HL)
	INC	HL
	LD	H,(HL)
	LD	L,C		; Service vector table address in HL
	POP	BC		; Requested call
	DEC	A		; Correct Max Call # for Testing
	JP	M,DIRIOX	; ..jump Error exit if 0 --> FF (No Calls)
	CP	C		; Greater than Maximum Function?
	JR	C,DIRIOX	; ..jump Error exit if so
	PUSH	BC		; Else Save BC
	LD	B,0
	ADD	HL,BC
	ADD	HL,BC		; Add twice for Word index
	LD	B,(HL)
	INC	HL
	LD	H,(HL)
	LD	L,B		; Put vector in HL
	POP	BC		; Restore User's BC register
	POP	AF		; .Restore A and Flags
	EX	(SP),HL		; ..restore HL, Vector to TOS
	RET			; Jump to Routine

DIRIOX:	POP	AF		; Clear stack
	POP	HL
	OR	0FFH		; Set Error return
	RET			; ..and quit

; Direct Disk Access Table Pointer Table

DDIOTB:	DEFB	0
	DEFW	00		; No Driver 0
	DEFB	MAXFFN
	DEFW	FDFUNC		; 1 is Primary Floppy Driver
	  IF  HARDDSK
	DEFB	MAXHFN
	DEFW	HDFUNC		; 2 is Primary Hard Disk Driver
	  ENDIF		;harddsk
	  IF  [RAMDSK AND NOT HARDDSK]
	DEFB	0
	DEFW	00		; (Dummy 2 if not installed)
	  ENDIF		;ramdsk and not harddsk
	  IF  RAMDSK
	DEFB	0
	DEFW	00		; 3 is Primary RAM Disk Driver (No Functions)
	  ENDIF		;ramdsk

MAXDDA	EQU	($-DDIOTB)/3	; Number of entries in pointer table

; Floppy Drive Function Table and Numbers

FDFUNC:	DEFW	STMODE		; 00 set mode
	DEFW	STSIZE		; 01 set drive size
	DEFW	STHDRV		; 02 set head and drive
	DEFW	STSECT		; 03 set sector #, size and eot
	DEFW	SPEC		; 04 specify srt, hlt, hut
	DEFW	RECAL		; 05 home the floppy
	DEFW	SEEK		; 06 seek track
	DEFW	SREAD		; 07 read
	DEFW	SWRITE		; 08 write
	DEFW	READID		; 09 read id
	DEFW	RETDST		; 10 return drive status & result ptr
	DEFW	FMTTRK		; 11 format a track
MAXFFN	EQU	[$-FDFUNC]/2

; Hard Disk Function Table and Numbers

	  IF  HARDDSK
HDFUNC:	DEFW	HDVALS		; 00 Set Xfer Address, Return Interface Parms
	DEFW	HDSLCT		; 01 Select Device (& Logical Unit w/SCSI)
	DEFW	HD_RW		; 02 Direct Hard Disk Driver
MAXHFN	EQU	[$-HDFUNC]/2
	  ENDIF		;harddsk
	PAGE
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
;	Banked   Memory   Support   Routines
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
;::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
;  Bank Control Routines.  Used only in Banked Systems
;::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

	  IF  BANKED		; << ****** HARDWARE SPECIFIC ****** >>
				; <<  Enter the Inter-Bank Movement  >>
	INCLUDE	IBMV-DX.Z80	; <<    routines in IBMV-xxx.Z80     >>

	  ELSE			; If Not Banked, Use these hooks

MOVE:	LDIR
	RET

SETBNK:
SELMEM:
RETMEM:
XMOVE:
GOSYSB:
FRCLR:
STFARC:	RET

FRJP:	JP	(HL)

FRGETB:	LD	A,(HL)
	RET

FRGETW:	LD	E,(HL)
	INC	HL
	LD	D,(HL)
	DEC	HL
	RET

FRPUTB:	LD	(HL),A
	RET

FRPUTW:	LD	(HL),E
	INC	HL
	LD	(HL),D
	DEC	HL
	RET

	  ENDIF		;(not) banked
	PAGE
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
;	Core   BIOS   Code
;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
;	Return  BIOS  Addresses
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

	CSEG

RETBIO:	LD	BC,BIOSJT	; Get address of bios base
	LD	DE,CONFIG	; Point to configuration area
	LD	HL,DEVCFG	; Point to Char IO Device Table
	LD	A,VERS		; Return BIOS Version
	RET

;::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
;	Return  DPH  Table  Address
;::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

DRVTBL:	LD	HL,DPHTBL	; Point to DPH table
	RET

	PAGE
	INCLUDE	BYTEIO.Z80	; Con:, aux:, lst: redirection
	PAGE
	INCLUDE	SELRWD.Z80	; Physical driver link for disks
	PAGE
	INCLUDE	DEBLOCK.Z80	; Hstbuf deblocker
	PAGE
	INCLUDE	SECTRAN.Z80	; Sector translation
	PAGE
	  IF  AUTOSL
	INCLUDE	SELFLP2.Z80	; Floppy disk select
	  ELSE
	INCLUDE	SELFLP1.Z80
	  ENDIF
	PAGE
	INCLUDE	FLOPPY.Z80	; Hardware independent floppy routines
	PAGE
				; << ****** Hardware Specific ****** >>
				; << This Driver is for the Standard >>
	INCLUDE	FDC-DX.Z80	; <<  MicroSystems (SMC) FDC37C665   >>
	PAGE
			 	; << ****** Hardware Specific ****** >>
				; <<  Enter routines for your timer  >>
	INCLUDE	TIM-DX.Z80	; <<    and clock in TIM-xxxx.Z80    >>
	PAGE

	  IF  HARDDSK		; << ****** Hardware Specific ****** >>
	   IF  IDE		; << Enter driver routines for your  >>
	INCLUDE	HARDIDE.Z80	; <<    Hard Disk in HARD-xxx.Z80    >>
	   ELSE
	INCLUDE	HARD-DX.Z80
	   ENDIF
	PAGE
	  ENDIF

	  IF  RAMDSK		; << ****** Hardware Specific ****** >>
	INCLUDE	RAMD-DX.Z80	; <<  Enter driver routines for RAM  >>
	PAGE			; <<      Disk in RAMD-xxx.Z80       >>
	  ENDIF
				; << ****** Hardware Specific ****** >>
				; <<   Enter Warm Boot routines in   >>
	INCLUDE	WBOOT-DX.Z80	; <<          WBOOT-xx.Z80           >>
;.....
; Status bytes of general use placed at end of Data area

	DSEG

HDONE:	DEFS	1		; HDC Flag 0=Ready, 1=Busy, 0FFH=Done
ERFLAG:	DEFS	1		; Disk Operation Error Code
	DEFS	3		; Reserved

; Add Character IO buffers here to insure they are at end of DSEG

	  IF  BUFFA0 AND MORDEV AND NOT MOVCPM
COM4Q:	DEFS	1		; Char count in Queue
	DEFS	QSIZE		; 1 to 255 character type-ahead buffer
	  ENDIF

	  IF  BUFFA1 AND MORDEV AND NOT MOVCPM
COM5Q:	DEFS	1		; Char count in Queue
	DEFS	QSIZE		; 1 to 255 character type-ahead buffer
	  ENDIF

	  IF  (BUFFA0 OR BUFFA1) AND MORDEV AND NOT MOVCPM
	DEFS	12		; Stack for Buffered char IO routines
INTSP:	DEFS	2		;  Storage for entry Stack Ptr
	  ENDIF

; Flags Bytes for Com1/Com2 Flow Control
	  IF  XONOFF
COM1WT:	DEFS	1		; B7=0 - Output Ok, B7=1 - Output Stopped
COM2WT:	DEFS	1		;   B0=0 - Input Ok, B0=1 - Input Halted
	   IF  ESCC_B AND MORDEV AND NOT MOVCPM
COM3WT:	DEFS	1		; Flags for Expansion devices
	   ENDIF
	   IF  ASCI_0 AND MORDEV AND NOT MOVCPM
COM4WT:	DEFS	1
	   ENDIF
	   IF  ASCI_1 AND MORDEV AND NOT MOVCPM
COM5WT:	DEFS	1
	   ENDIF
	  ENDIF		;XonOff

PAOR:	DEFS	1		; Parallel Output Ready Flag

	  IF  [BANKED AND ZSDOS2]
	COMMON	/B2RAM/			; Put this label in Banked Memory
	  ENDIF				; ..else in Dseg
BRAME:	DEFS	2		; Use as dynamic sizing label for Hard Drive
				; ALV buffers, and storage area for sizing.
				; ALV Buffers build up from here in memory
	CSEG

; Display warning if we are assembling for MOVCPM integration and the
; combined CSEG/Initialized DSEG size exceeds 1 or 2 Boot Records

PRINTX	  MACRO	%NN
	.printx	%NN
	  ENDM

LIMIT	EQU	$-BIOSJT+INITCS

	  IF  MOVCPM AND LIMIT > 4480
	.printx
	.printx	**** BIOS too big (>4480) for Boot Tracks! ****
	PRINTX	%LIMIT
	.printx
	  ELSE
	   IF  MOVCPM AND LIMIT > 4352
	.printx
	.printx ++++ BIOS exceeds (>4352) 2-Sector Boot Record ++++
	PRINTX	%LIMIT
	.printx
	   ENDIF
	  ENDIF

NSECTS	EQU	($+INITCS-BIOSJT)/128+1
	  IF  INROM
	INCLUDE	BOOTRAM.Z80
	  ENDIF
	END