AppleIISd/AppleIISd.s

777 lines
19 KiB
ArmAsm

********************************
*
* Apple][Sd Firmware
* Version 0.6
*
* (c) Florian Reitz, 2017
*
* X register usually contains SLOT16
* Y register is used for counting or SLOT
*
********************************
DAT
XC ; enable 65C02 code
DEBUG = 0
DO DEBUG
ORG $8000
ELSE
ORG $C800 ; Expansion ROM
FIN
* Memory defines
SLOT16 = $2B ; $s0 -> slot * 16
WORK = $3C
SLOT = $3D ; $0s
CMDLO = $40
CMDHI = $41
CURSLOT = $07F8 ; $Cs
DATA = $C080
CTRL = DATA+1
DIV = DATA+2
SS = DATA+3
R30 = $0478
R31 = $04F8
R32 = $0578
R33 = $05F8
* Constants
DUMMY = $FF
FRX = $10 ; CTRL register
ECE = $04
SS0 = $01 ; SS register
WP = $20
CD = $40
INITED = $80
* signature bytes
LDX #$20
LDY #$00
LDX #$03
LDY #$FF ; neither 5.25 nor Smartport
* find slot nr
DO DEBUG
LDA #$04
STA SLOT
LDA #$C4
STA CURSLOT
LDA #$40
STA SLOT16
ELSE
JSR $FF58
TSX
LDA $0100,X
STA CURSLOT ; $Cs
AND #$0F
STA SLOT ; $0s
ASL A
ASL A
ASL A
ASL A
STA SLOT16 ; $s0
FIN
TAX ; X holds now SLOT16
BIT $CFFF
JSR CARDDET
BCC :INIT
LDA #$27 ; no card inserted
BRK
:INIT JSR INIT
********************************
*
* Install SD card driver
*
********************************
DO DEBUG
* see if slot has a driver already
LDX $BF31 ; get devcnt
INSTALL LDA $BF32,X ; get a devnum
AND #$70 ; isolate slot
CMP SLOT16 ; slot?
BEQ :INSOUT ; yes, skip it
DEX
BPL INSTALL ; keep up the search
* restore the devnum to the list
LDX $BF31 ; get devcnt again
CPX #$0D ; device table full?
BNE :INST2
JSR $FF3A ; bell
JMP :INSOUT ; do something!
:INST2 LDA $BF32-1,X ; move all entries down
STA $BF32,X ; to make room at front
DEX ; for a new entry
BNE :INST2
LDA #$04 ; ProFile type device
ORA SLOT16
STA $BF32 ; slot, drive 1 at top of list
INC $BF31 ; update devcnt
* now insert the device driver vector
LDA SLOT
ASL
TAX
LDA #<DRIVER
STA $BF10,X ; write to driver table
LDA #>DRIVER
STA $BF11,X
:INSOUT RTS
********************************
*
* Boot from SD card
*
********************************
ELSE
BOOT CMP #0 ; check for error
BEQ :BOOT1
BRK
:BOOT1 LDA #$01
STA $42 ; load command
LDA SLOT16
TAX
STA $43 ; slot number
STZ $44 ; buffer lo
LDA #$08
STA $45 ; buffer hi
STZ $46 ; block lo
STZ $47 ; block hi
BIT $CFFF
JSR READ ; call driver
JMP $801 ; goto bootloader
FIN
********************************
*
* Jump table
*
********************************
DRIVER CLD
DO DEBUG
LDA #$04
STA SLOT
LDA #$C4
STA CURSLOT
LDA #$40
STA SLOT16
ELSE
JSR $FF58 ; find slot nr
TSX
LDA $0100,X
STA CURSLOT ; $Cs
AND #$0F
STA SLOT ; $0s
ASL A
ASL A
ASL A
ASL A
STA SLOT16 ; $s0
FIN
TAX ; X holds now SLOT16
BIT $CFFF
JSR CARDDET
BCC :INITED
LDA #$27 ; no card inserted
BRA :DONE
:INITED LDA #INITED ; check for init
BIT SS,X
BEQ :INIT
:CMD LDA $42 ; get command
CMP #0
BEQ :STATUS
CMP #1
BEQ :READ
CMP #2
BEQ :WRITE
CMP #3
BEQ :FORMAT
LDA #1 ; unknown command
:DONE SEC
RTS
:STATUS JMP STATUS
:READ JMP READ
:WRITE JMP WRITE
:FORMAT JMP FORMAT
:INIT JSR INIT
BCS :DONE ; init failure
BRA :CMD
* Signature bytes
DS \ ; fill with zeroes
DS -4 ; locate to $xxFC
DW $FFFF ; 65535 blocks
DB $17 ; Status bits
DB #<DRIVER ; LSB of driver
********************************
*
* Initialize SD card
*
* C Clear - No error
* Set - Error
* A $00 - No error
* $27 - I/O error - Init failed
* $2F - No card inserted
*
********************************
INIT CLD
LDA #$03 ; set SPI mode 3
STA CTRL,X
LDA SS,X
ORA #SS0 ; set CS high
STA SS,X
LDA #7
STA DIV,X
LDY #10
LDA #DUMMY
:LOOP STA DATA,X
:WAIT BIT CTRL,X
BPL :WAIT
DEY
BNE :LOOP ; do 10 times
LDA SS,X
AND #$FF!SS0 ; set CS low
STA SS,X
LDA #<CMD0 ; send CMD0
STA CMDLO
LDA #>CMD0
STA CMDHI
JSR CMD
JSR GETR1 ; get response
CMP #$01
BNE :ERROR1 ; error!
LDA #<CMD8 ; send CMD8
STA CMDLO
LDA #>CMD8
STA CMDHI
JSR CMD
JSR GETR3
CMP #$01
BNE :SDV1 ; may be SD Ver. 1
* check for $01aa match!
:SDV2 LDA #<CMD55
STA CMDLO
LDA #>CMD55
STA CMDHI
JSR CMD
JSR GETR1
LDA #<ACMD4140
STA CMDLO
LDA #>ACMD4140
STA CMDHI
JSR CMD
JSR GETR1
CMP #$01
BEQ :SDV2 ; wait for ready
CMP #$00
BNE :ERROR1 ; error!
* send CMD58
* SD Ver. 2 initialized!
JMP :BLOCKSZ
:ERROR1 JMP :IOERROR ; needed for far jump
:SDV1 LDA #<CMD55
STA CMDLO
LDA #>CMD55
STA CMDHI
JSR CMD ; ignore response
LDA #<ACMD410
STA CMDLO
LDA #>ACMD410
STA CMDHI
JSR CMD
JSR GETR1
CMP #$01
BEQ :SDV1 ; wait for ready
CMP #$00
BNE :MMC ; may be MMC card
* SD Ver. 1 initialized!
JMP :BLOCKSZ
:MMC LDA #<CMD1
STA CMDLO
LDA #>CMD1
STA CMDHI
:LOOP1 JSR CMD
JSR GETR1
CMP #$01
BEQ :LOOP1 ; wait for ready
CMP #$00
BNE :IOERROR ; error!
* MMC Ver. 3 initialized!
:BLOCKSZ LDA #<CMD16
STA CMDLO
LDA #>CMD16
STA CMDHI
JSR CMD
JSR GETR1
CMP #$00
BNE :IOERROR ; error!
:END LDA SS,X
ORA #INITED ; initialized
STA SS,X
LDA CTRL,X
ORA #ECE ; enable 7MHz
STA CTRL,X
CLC ; all ok
LDY #0
BCC :END1
:CDERROR SEC
LDY #$2F ; no card error
BCS :END1
:IOERROR SEC
LDY #$27 ; init error
:END1 LDA SS,X ; set CS high
ORA #SS0
STA SS,X
LDA #0 ; set div to 2
STA DIV,X
TYA ; retval in A
RTS
********************************
*
* Send SD command
* Call with command in CMDHI and CMDLO
*
********************************
CMD PHY
LDY #0
:LOOP LDA (CMDLO),Y
STA DATA,X
:WAIT BIT CTRL,X ; TC is in N
BPL :WAIT
INY
CPY #6
BCC :LOOP
PLY
RTS
********************************
*
* Get R1
* R1 is in A
*
********************************
GETR1 LDA #DUMMY
STA DATA,X
:WAIT BIT CTRL,X
BPL :WAIT
LDA DATA,X ; get response
STA WORK ; save R1
AND #$80
BNE GETR1 ; wait for MSB=0
LDA #DUMMY
STA DATA,X ; send another dummy
LDA WORK ; restore R1
RTS
********************************
*
* Get R3
* R1 is in A
* R3 is in scratchpad ram
*
********************************
GETR3 JSR GETR1 ; get R1 first
PHA ; save R1
PHY ; save Y
LDY #04 ; load counter
:LOOP LDA #DUMMY ; send dummy
STA DATA,X
:WAIT BIT CTRL,X
BPL :WAIT
LDA DATA,X
PHA
DEY
BNE :LOOP ; do 4 times
LDY SLOT
PLA
STA R33,Y ; save R3
PLA
STA R32,Y
PLA
STA R31,Y
PLA
STA R30,Y
PLY ; restore Y
LDA #DUMMY
STA DATA,X ; send another dummy
PLA ; restore R1
RTS
********************************
*
* Calculate block address
* Unit number is in $43 DSSS0000
* Block no is in $46-47
* Address is in R30-R33
*
********************************
BLOCK PHX ; save X
PHY ; save Y
LDX SLOT
LDA $46 ; store block num
STA R33,X ; in R30-R33
LDA $47
STA R32,X
LDA #0
STA R31,X
STA R30,X
LDA #$80 ; drive number
BIT $43
BEQ :SHIFT ; D1
LDA #1 ; D2
STA R31,X
:SHIFT LDY #9 ; ASL can't be used with Y
:LOOP ASL R33,X ; mul block num
ROL R32,X ; by 512 to get
ROL R31,X ; real address
ROL R30,X
DEY
BNE :LOOP
PLY ; restore Y
PLX ; restore X
RTS
********************************
*
* Send SD command
* Cmd is in A
*
********************************
COMMAND PHY ; save Y
LDY SLOT
STA DATA,X ; send command
LDA R30,Y ; get arg from R30 on
STA DATA,X
LDA R31,Y
STA DATA,X
LDA R32,Y
STA DATA,X
LDA R33,Y
STA DATA,X
LDA #DUMMY
STA DATA,X ; dummy crc
JSR GETR1
PLY ; restore Y
RTS
********************************
*
* Check for card detect
*
* C Clear - card in slot
* Set - no card in slot
*
********************************
CARDDET PHA
LDA #CD ; 0: card in
BIT SS,X ; 1: card out
CLC
BEQ :DONE ; card is in
SEC ; card is out
:DONE PLA
RTS
********************************
*
* Check for write protect
*
* C Clear - card not protected
* Set - card write protected
*
********************************
WRPROT PHA
LDA #WP ; 0: write enabled
BIT SS,X ; 1: write disabled
CLC
BEQ :DONE
SEC
:DONE PLA
RTS
********************************
*
* Status request
* $43 Unit number DSSS000
* $44-45 Unused
* $46-47 Unused
*
* C Clear - No error
* Set - Error
* A $00 - No error
* $2B - Card write protected
* $2F - No card inserted
* X - Blocks avail (low byte)
* Y - Blocks avail (high byte)
*
********************************
STATUS LDA #0 ; no error
LDX #$FF ; 32 MB partition
LDY #$FF
JSR CARDDET
BCC :WRPROT
LDA #$2F ; no card inserted
BRA :DONE
:WRPROT JSR WRPROT
BCC :DONE
LDA #$2B ; card write protected
:DONE RTS
********************************
*
* Read 512 byte block
* $43 Unit number DSSS0000
* $44-45 Address (LO/HI) of buffer
* $46-47 Block number (LO/HI)
*
* C Clear - No error
* Set - Error
* A $00 - No error
* $27 - Bad block number
* $28 - No card inserted
*
********************************
READ JSR CARDDET
BCS :ERROR ; no card inserted
JSR BLOCK ; calc block address
LDA SS,X ; enable /CS
AND #$FF!SS0
STA SS,X
LDA #$51 ; send CMD17
JSR COMMAND ; send command
CMP #0 ; check for error
BNE :ERROR
:GETTOK LDA #DUMMY ; get data token
STA DATA,X
LDA DATA,X ; get response
CMP #$FE
BNE :GETTOK ; wait for $FE
LDY #2 ; read data from card
LDA CTRL,X ; enable FRX
ORA #FRX
STA CTRL,X
LDA #DUMMY
STA DATA,X
:LOOPY STZ WORK
:LOOPW LDA DATA,X
STA ($44)
INC $44
BNE :INW
INC $45 ; inc msb on page boundary
:INW INC WORK
BNE :LOOPW
DEY
BNE :LOOPY
:CRC LDA DATA,X ; read two bytes crc
LDA DATA,X ; and ignore
LDA DATA,X ; read a dummy byte
LDA CTRL,X ; disable FRX
AND #$FF!FRX
STA CTRL,X
CLC ; no error
LDA #0
:DONE PHP
PHA
LDA SS,X
ORA #SS0
STA SS,X ; disable /CS
PLA
PLP
RTS
:ERROR SEC ; an error occured
LDA #$27
BRA :DONE
********************************
*
* Write 512 byte block
* $43 Unit number DSSS0000
* $44-45 Address (LO/HI) of buffer
* $46-47 Block number (LO/HI)
*
* C Clear - No error
* Set - Error
* A $00 - No error
* $27 - I/O error or bad block number
* $2B - Card write protected
*
********************************
WRITE JSR CARDDET
BCS :IOERROR ; no card inserted
JSR WRPROT
BCS :WPERROR ; card write protected
JSR BLOCK ; calc block address
LDA SS,X ; enable /CS
AND #$FF!SS0
STA SS,X
LDA #$58 ; send CMD24
JSR COMMAND ; send command
CMP #0 ; check for error
BNE :IOERROR
LDA #DUMMY
STA DATA,X ; send dummy
LDA #$FE
STA DATA,X ; send data token
LDY #2 ; send data to card
:LOOPY STZ WORK
:LOOPW LDA ($44)
STA DATA,X
INC $44
BNE :INW
INC $45 ; inc msb on page boundary
:INW INC WORK
BNE :LOOPW
DEY
BNE :LOOPY
:CRC STA DATA,X ; send 2 dummy crc bytes
STA DATA,X
STA DATA,X ; get data response
LDA DATA,X
AND #$1F
CMP #$05
BNE :IOERROR ; check for write error
CLC ; no error
LDA #0
:DONE PHP
PHA
:WAIT LDA #DUMMY
STA DATA,X ; wait for write cycle
LDA DATA,X ; to complete
CMP #$00
BEQ :WAIT
LDA SS,X ; disable /CS
ORA #SS0
STA SS,X
PLA
PLP
RTS
:IOERROR SEC ; an error occured
LDA #$27
BRA :DONE
:WPERROR SEC
LDA #$2B
BRA :DONE
********************************
*
* Format
* not supported!
*
********************************
FORMAT SEC
LDA #$01 ; invalid command
RTS
CMD0 HEX 400000
HEX 000095
CMD1 HEX 410000
HEX 0000F9
CMD8 HEX 480000
HEX 01AA87
CMD16 HEX 500000
HEX 0200FF
CMD55 HEX 770000
HEX 000065
ACMD4140 HEX 694000
HEX 000077
ACMD410 HEX 690000
HEX 0000FF