AppleWin/firmware/HDD/hddrvr.a65

316 lines
7.3 KiB
Plaintext

;AppleWin : An Apple //e emulator for Windows
;
;Copyright (C) 1994-1996, Michael O'Brien
;Copyright (C) 1999-2001, Oliver Schmidt
;Copyright (C) 2002-2005, Tom Charlesworth
;Copyright (C) 2006-2012, Tom Charlesworth, Michael Pohoreski
;
;AppleWin 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.
;
;AppleWin 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 AppleWin; if not, write to the Free Software
;Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
;
; Description: Firmware for harddisk card
;
; Author: Copyright (c) 2005, Robert Hoem
;
; Modified by Tom Charlesworth:
; . Updated so it can be assembled by ACME 0.96.4
; . Fixed so that ProDOS entrypoint is $c70a (26 Dev 2007) (Bug #12723)
; . Modified to support Apple Oasis' entrypoint: $c761 (8 Sept 2012) (Feature #5557)
; . Added support for SmartPort entrypoint (20 Oct 2012)
; - EG. "Prince of Persia (Original 3.5 floppy for IIc+).2mg"
; . GH#370 (Robert Hoem, 27 Oct 2016):
; . Added a check against open-apple during boot to route boot to slot 6
; . This happens after the first two blocks are loaded from the HD.
; . GH#319: smartport return address wrong when crossing page
; TODO:
; . Make code relocatable (so HDD controller card can go into any slot)
; . Remove support for Entrypoint_C746 (old AppleWin) & Entrypoint_C761 (Apple Oasis)
; - provide a utility to convert these to use Entrypoint_ProDOS
; . Check SmartPort: Is it OK to trash Y and $42,..,$47 ?
;
!cpu 6502 ; Compatible with all Apple2's
!to "hddrvr.bin", plain
!sl "hddrvr.labels"
; constants
hd_execute = $c0f0
hd_error = $c0f1
hd_command = $c0f2
hd_unitnum = $c0f3
hd_memblock = $c0f4
hd_diskblock = $c0f6
hd_nextbyte = $c0f8
command = $42
unitnum = $43
memblock = $44
diskblock = $46
slot6 = $c600
OS = $0801
BUTTON0 = $C061
; The Autoboot rom will call this.
; This is also the entry point for such things as IN#7 and PR#7
;; code
*= $c700 ; org $c700
!zone code
start
; Autoboot and ProDOS look at the following few opcodes to detect block devices
; NB. $Cn07 should be $00 for a SmartPort Interface, but changing this means that it won't autoboot on ][, ][+ and unenhanced IIe.
; . ref: http://www.1000bit.it/support/manuali/apple/technotes/udsk/tn.udsk.2.html
lda #$20
lda #$00
lda #$03
lda #$3C
bne Bootstrap
Entrypoint_ProDOS ; $c70a - ProDOS entrypoint
sec
bcs Entrypoint
Entrypoint_SmartPort ; $c70d - SmartPort entrypoint
clc
Entrypoint ; $c70e - entrypoint?
bcs cmdproc
bcc SmartPort
;;
Bootstrap
; Lets check to see if there's an image ready
lda #$00
sta hd_command
; Slot 7, disk 1
lda #$70 ; Slot# << 4
sta hd_unitnum
lda hd_execute
; error capturing code. Applewin is picky
; about code assigning data to registers and
; memory. The safest method is via I/O port
ror hd_error ; Post: C=0 or 1
bcc hdboot
; no image ready, boot diskette image instead
BootSlot6
jmp slot6
;======================================
; TODO: Is it OK to trash Y and $42,..,$47 ?
; Pre: C=0
SmartPort
pla
sta $46
adc #3 ; Pre: C=0, Post: C=0 or 1
tay
pla
sta $47 ; ($46) = &cmd_hdr
adc #0
pha
tya
pha ; (sp).w += 3
ldy #1
lda ($46),y ; cmd
sta $42
iny
bne SmartPort2
;======================================
; 8 unused bytes
*= $c746 ; org $c746
Entrypoint_C746 ; Old f/w 'cmdproc' entrypoint
; Keep this for any DOSMaster HDD images created with old AppleWin HDD f/w.
; DOSMaster hardcodes the entrypoint addr into its bootstrapping code:
; - So DOSMaster images are tied to the HDD's controller's f/w
sec
bcs Entrypoint
;======================================
; Pre: Y=2
SmartPort2
lda ($46),y ; param_l
sta $45
iny
lda ($46),y ; param_h
sta $46
ldy #1 ; skip paramLength (assume it's #$03)
lda ($45),y ; unit
sta $43
iny
lda ($45),y ; memblock_l
sta $44
iny
bne SmartPort3
;======================================
; 1 unused byte
*= $c761 ; org $c761
Entrypoint_C761 ; Apple Oasis HDD controller entrypoint
; Keep this for any DOSMaster HDD images created with Apple Oasis HDD f/w.
; DOSMaster hardcodes the entrypoint addr into its bootstrapping code:
; - So DOSMaster images are tied to the HDD's controller's f/w
sec
bcs Entrypoint
;======================================
; image ready. Lets boot from it.
; we want to load block 1 from s7,d1 to $800 then jump there
hdboot
lda #$70 ; Slot# << 4
sta unitnum
lda #$0
sta memblock
sta diskblock
sta diskblock+1
lda #$8
sta memblock+1
lda #$1
sta command
jsr cmdproc
bcs BootSlot6
goload
bit BUTTON0 ; button 0 pressed?
bmi BootSlot6
; X=device
ldx #$70 ; Slot# << 4
jmp OS
; entry point for ProDOS' block driver
; simple really. Copy the command from $42..$47
; to our I/O ports then execute command
cmdproc
clc
lda $42
sta hd_command
lda $43
sta hd_unitnum
lda $44
sta hd_memblock
lda $45
sta hd_memblock+1
lda $46
sta hd_diskblock
lda $47
sta hd_diskblock+1
lda hd_execute
; check for error
pha
lda command
cmp #1
bne skipSread
jsr sread
skipSread
ror hd_error ; Post: C=0 or 1
pla
rts
; if there's no error, then lets read the block into memory
; because Applewin is picky about memory management, here's what I did:
; on read, hd_nextbyte = buffer[0], therefore we'll read that byte 256 times (in which
; the emulated code increments the buffer by 1 on each read) to (memblock),y
; increment memblock+1 and read the second 256 bytes via hd_nextbyte.
;
; if I could figure out how to consistently get applewin to update it's memory regions all
; this code can be moved into the emulation code (although, this is how I'd build the hardware
; anyway...)
sread
tya
pha
ldy #0
loop1
lda hd_nextbyte
sta (memblock),y
iny
bne loop1
inc memblock+1
ldy #0
loop2
lda hd_nextbyte
sta (memblock),y
iny
bne loop2
dec memblock+1 ; restore memblock+1 ($45) to original value (for Epyx's California Games)
pla
tay
rts
;======================================
SmartPort3
lda ($45),y ; memblock_h
pha
iny
lda ($45),y ; diskblock_l
pha
iny
lda ($45),y ; diskblock_h
sta $47
pla
sta $46
pla
sta $45
iny
bne cmdproc
;======================================
; 18 unused bytes
!zone data
; $CsFE = status bits (BAP p7-14)
; 7 = medium is removable
; 6 = device is interruptable
; 5-4 = number of volumes (0..3 means 1..4)
; 3 = device supports Format call
; 2 = device can be written to
; 1 = device can be read from (must be 1)
; 0 = device status can be read (must be 1)
; $C7 = Removable, Interruptable, #Volumes=1, Supports write/read/status
; $D7 = Removable, Interruptable, #Volumes=2, Supports write/read/status
; $BF = Removable, Interruptable, #Volumes=4, Supports format/write/read/status (KEGS / IIGS)
; datablock. This starts near the end of the firmware (at offset $FC)
;; data
*= $c7fc ; org $c7fc
!word $7fff ; how many blocks are on the device.
!byte $D7 ; specifics about the device (number of drives, read/write/format capability, etc)
!byte <Entrypoint_ProDOS ; entry point offset for ProDOS (must be $0a)