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Florian Reitz 2017-12-19 15:15:53 +01:00
commit 06efc602c4
7 changed files with 528 additions and 594 deletions
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BIN
AppleIISd.bin
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3
AppleIISd.vcxproj
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@ -15,7 +15,10 @@
<None Include="obj\AppleIISd.lst" />
<None Include="README.md" />
<None Include="src\AppleIISd.cfg" />
<None Include="src\AppleIISd.inc" />
<None Include="src\AppleIISd.s" />
<None Include="src\Helper.s" />
<None Include="src\ProDOS.s" />
</ItemGroup>
<PropertyGroup Label="Globals">
<ProjectGuid>{9EA7EC3D-1771-420F-932F-231A35ED1200}</ProjectGuid>

9
AppleIISd.vcxproj.filters
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@ -10,6 +10,15 @@
</None>
<None Include="README.md" />
<None Include="obj\AppleIISd.lst" />
<None Include="src\Helper.s">
<Filter>src</Filter>
</None>
<None Include="src\AppleIISd.inc">
<Filter>src</Filter>
</None>
<None Include="src\ProDOS.s">
<Filter>src</Filter>
</None>
</ItemGroup>
<ItemGroup>
<Filter Include="src">

45
src/AppleIISd.inc Normal file
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@ -0,0 +1,45 @@
;*******************************
;
; Apple][Sd Firmware
; Version 1.1
; Defines
;
; (c) Florian Reitz, 2017
;
; X register usually contains SLOT16
; Y register is used for counting or SLOT
;
;*******************************
; Memory defines
SLOT16 := $2B ; $s0 -> slot * 16
SLOT := $3D ; $0s
CMDLO := $40
CMDHI := $41
DCMD := $42 ; Command code
BUFFER := $44 ; Buffer address
BLOCK := $46 ; Block number
R30 := $0478
R31 := $04F8
R32 := $0578
R33 := $05F8
CURSLOT := $07F8 ; $Cs
OAPPLE := $C061 ; open apple key
DATA := $C080
CTRL := DATA+1
DIV := DATA+2
SS := DATA+3
; Constants
DUMMY = $FF
FRX = $10 ; CTRL register
ECE = $04
SS0 = $01 ; SS register
SDHC = $10
WP = $20
CD = $40
INITED = $80

604
src/AppleIISd.s
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@ -2,6 +2,7 @@
;
; Apple][Sd Firmware
; Version 1.1
; Main source
;
; (c) Florian Reitz, 2017
;
@ -10,43 +11,42 @@
;
;*******************************
.define DEBUG 0
.import GETR1
.import GETR3
.import SDCMD
.import CARDDET
.import STATUS
.import READ
.import WRITE
; Memory defines
SLOT16 := $2B ; $s0 -> slot * 16
SLOT := $3D ; $0s
CMDLO := $40
CMDHI := $41
DCMD := $42 ; Command code
BUFFER := $44 ; Buffer address
BLOCK := $46 ; Block number
R30 := $0478
R31 := $04F8
R32 := $0578
R33 := $05F8
CURSLOT := $07F8 ; $Cs
OAPPLE := $C061 ; open apple key
DATA := $C080
CTRL := DATA+1
DIV := DATA+2
SS := DATA+3
; Constants
DUMMY = $FF
FRX = $10 ; CTRL register
ECE = $04
SS0 = $01 ; SS register
SDHC = $10
WP = $20
CD = $40
INITED = $80
.include "AppleIISd.inc"
; signature bytes
;*******************************
;
; Signature bytes
;
; 65535 blocks
; Removable media
; Non-interruptable
; 2 drives
; Read, write and status allowed
;
;*******************************
.segment "SLOTID"
.dbyt $FFFF ; 65535 blocks
.byt $97 ; Status bits
.byt <DRIVER ; LSB of driver
;*******************************
;
; Bootcode
;
; Is executed on boot or PR#
;
;*******************************
.segment "SLOTROM"
LDX #$20
@ -55,15 +55,6 @@ INITED = $80
LDX #$3C
; find slot nr
.if DEBUG
LDA #$04
STA SLOT
LDA #$C4
STA CURSLOT
LDA #$40
.else
PHP
SEI
LDA #$60 ; opcode for RTS
@ -79,7 +70,6 @@ INITED = $80
ASL A
ASL A
ASL A
.endif
STA SLOT16 ; $s0
TAX ; X holds now SLOT16
@ -107,61 +97,12 @@ INITED = $80
@INIT: JSR INIT
;*******************************
;
; Install SD card driver
;
;*******************************
.if 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
; BNE @NEXTSLOT ; init not successful
@BOOT: LDA #$01
@ -190,7 +131,6 @@ INITED = $80
JSR READ ; call driver
LDX SLOT16
JMP $801 ; goto bootloader
.endif
;*******************************
@ -210,15 +150,6 @@ DRIVER: CLD
PHA
LDA CMDHI
PHA
.if DEBUG
LDA #$04
STA SLOT
LDA #$C4
STA CURSLOT
LDA #$40
.else
PHP
SEI
LDA #$60 ; opcode for RTS
@ -234,7 +165,6 @@ DRIVER: CLD
ASL A
ASL A
ASL A
.endif
STA SLOT16 ; $s0
TAX ; X holds now SLOT16
@ -254,10 +184,6 @@ DRIVER: CLD
BEQ @READ
CMP #2
BEQ @WRITE
.if DEBUG
CMP #$FF
BEQ @TEST
.endif
LDA #1 ; unknown command
SEC
BRA @RESTZP
@ -268,10 +194,6 @@ DRIVER: CLD
BRA @RESTZP
@WRITE: JSR WRITE
BRA @RESTZP
.if DEBUG
@TEST: JSR TEST ; do device test
BRA @RESTZP
.endif
@INIT: JSR INIT
BCC @CMD ; init ok
@ -290,24 +212,6 @@ DRIVER: CLD
RTS
;*******************************
;
; Signature bytes
;
; 65535 blocks
; Removable media
; Non-interruptable
; 2 drives
; Read, write and status allowed
;
;*******************************
.segment "SLOTID"
.dbyt $FFFF ; 65535 blocks
.byt $97 ; Status bits
.byt <DRIVER ; LSB of driver
;*******************************
;
; Initialize SD card
@ -461,445 +365,6 @@ INIT: LDA #$03 ; set SPI mode 3
RTS
;*******************************
;
; Send SD command
; Call with command in CMDHI and CMDLO
;
;*******************************
SDCMD: 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
BIT #$80
BNE GETR1 ; wait for MSB=0
PHA
LDA #DUMMY
STA DATA,X ; send another dummy
PLA ; restore R1
RTS
;*******************************
;
; Get R3 or R7
; 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
JMP @WAIT ; first byte is already there
@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 ; R30 is MSB
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
;
;*******************************
GETBLOCK: PHX ; save X
PHY ; save Y
TXA
TAY ; SLOT16 is now in Y
LDX SLOT
LDA BLOCK ; store block num
STA R33,X ; in R30-R33
LDA BLOCK+1
STA R32,X
LDA #0
STA R31,X
STA R30,X
LDA #$80 ; drive number
AND $43
BEQ @SDHC ; D1
LDA #1 ; D2
STA R31,X
@SDHC: LDA #SDHC
AND SS,Y ; if card is SDHC,
BNE @END ; use block addressing
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
@END: 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
JSR WRPROT
BCC @DONE
LDA #$2B ; card write protected
@DONE: LDX #$FF ; 32 MB partition
LDY #$FF
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
;
;*******************************
READ: JSR GETBLOCK ; calc block address
LDA SS,X ; enable /CS
AND #<~SS0
STA SS,X
LDA #$51 ; send CMD17
JSR COMMAND ; send command
CMP #0
BNE @ERROR ; check for error
@GETTOK: LDA #DUMMY ; get data token
STA DATA,X
LDA DATA,X ; get response
CMP #$FE
BNE @GETTOK ; wait for $FE
LDA CTRL,X ; enable FRX
ORA #FRX
STA CTRL,X
LDA #DUMMY
STA DATA,X
LDY #0
@LOOP1: LDA DATA,X ; read data from card
STA (BUFFER),Y
INY
BNE @LOOP1
INC BUFFER+1 ; inc msb on page boundary
@LOOP2: LDA DATA,X
STA (BUFFER),Y
INY
BNE @LOOP2
DEC BUFFER+1
@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 #<~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 WRPROT
BCS @WPERROR ; card write protected
JSR GETBLOCK ; calc block address
LDA SS,X ; enable /CS
AND #<~SS0
STA SS,X
LDA #$58 ; send CMD24
JSR COMMAND ; send command
CMP #0
BNE @IOERROR ; check for error
LDA #DUMMY
STA DATA,X ; send dummy
LDA #$FE
STA DATA,X ; send data token
LDY #0
@LOOP1: LDA (BUFFER),Y
STA DATA,X
INY
BNE @LOOP1
INC BUFFER+1
@LOOP2: LDA (BUFFER),Y
STA DATA,X
INY
BNE @LOOP2
DEC BUFFER+1
@CRC: LDA #DUMMY
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
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
;*******************************
;
; Test routine
;
;*******************************
.if DEBUG
TEST: LDA SLOT16
PHA
LDA SLOT
PHA
; get buffer
LDA #2 ; get 512 byte buffer
JSR $BEF5 ; call GETBUFR
BCS @ERROR
STA BUFFER+1
STZ BUFFER
PLA
STA SLOT
PLA
STA SLOT16
; fill buffer
LDY #0
@LOOP: TYA
STA (BUFFER),Y
INY
BNE @LOOP
INC BUFFER+1
@LOOP1: TYA
STA (BUFFER),Y
INY
BNE @LOOP1
DEC BUFFER+1
STZ BLOCK ; block number
STZ BLOCK+1
LDX SLOT16
; write to card
JSR WRITE
BCS @ERROR
; read from card
JSR READ
BCS @ERROR
; check for errors
LDY #0
@LOOP2: TYA
CMP (BUFFER),Y
BNE @ERRCMP ; error in buffer
INY
BNE @LOOP2
INC BUFFER+1
@LOOP3: TYA
CMP (BUFFER),Y
BNE @ERRCMP
INY
BNE @LOOP3
DEC BUFFER+1
; free buffer
JSR $BEF8 ; call FREEBUFR
CLC
LDA #0
RTS
@ERROR: BRK
@ERRCMP: BRK
.endif
TEXT: .asciiz " Apple][Sd v1.1 (c)2017 Florian Reitz"
CMD0: .byt $40, $00, $00
@ -918,4 +383,3 @@ ACMD4140: .byt $69, $40, $00
.byt $00, $00, $77
ACMD410: .byt $69, $00, $00
.byt $00, $00, $FF

208
src/Helper.s Normal file
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@ -0,0 +1,208 @@
;*******************************
;
; Apple][Sd Firmware
; Version 1.1
; Helper functions
;
; (c) Florian Reitz, 2017
;
; X register usually contains SLOT16
; Y register is used for counting or SLOT
;
;*******************************
.export COMMAND
.export SDCMD
.export GETBLOCK
.export CARDDET
.export WRPROT
.export GETR1
.export GETR3
.include "AppleIISd.inc"
.segment "EXTROM"
;*******************************
;
; Send SD command
; Call with command in CMDHI and CMDLO
;
;*******************************
SDCMD: 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
BIT #$80
BNE GETR1 ; wait for MSB=0
PHA
LDA #DUMMY
STA DATA,X ; send another dummy
PLA ; restore R1
RTS
;*******************************
;
; Get R3 or R7
; 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
JMP @WAIT ; first byte is already there
@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 ; R30 is MSB
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
;
;*******************************
GETBLOCK: PHX ; save X
PHY ; save Y
TXA
TAY ; SLOT16 is now in Y
LDX SLOT
LDA BLOCK ; store block num
STA R33,X ; in R30-R33
LDA BLOCK+1
STA R32,X
LDA #0
STA R31,X
STA R30,X
LDA #$80 ; drive number
AND $43
BEQ @SDHC ; D1
LDA #1 ; D2
STA R31,X
@SDHC: LDA #SDHC
AND SS,Y ; if card is SDHC,
BNE @END ; use block addressing
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
@END: 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

205
src/ProDOS.s Normal file
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@ -0,0 +1,205 @@
;*******************************
;
; Apple][Sd Firmware
; Version 1.1
; ProDOS functions
;
; (c) Florian Reitz, 2017
;
; X register usually contains SLOT16
; Y register is used for counting or SLOT
;
;*******************************
.export STATUS
.export READ
.export WRITE
.import COMMAND
.import SDCMD
.import GETBLOCK
.import WRPROT
.import GETR1
.import GETR3
.include "AppleIISd.inc"
.segment "EXTROM"
;*******************************
;
; 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
JSR WRPROT
BCC @DONE
LDA #$2B ; card write protected
@DONE: LDX #$FF ; 32 MB partition
LDY #$FF
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
;
;*******************************
READ: JSR GETBLOCK ; calc block address
LDA SS,X ; enable /CS
AND #<~SS0
STA SS,X
LDA #$51 ; send CMD17
JSR COMMAND ; send command
CMP #0
BNE @ERROR ; check for error
@GETTOK: LDA #DUMMY ; get data token
STA DATA,X
LDA DATA,X ; get response
CMP #$FE
BNE @GETTOK ; wait for $FE
LDA CTRL,X ; enable FRX
ORA #FRX
STA CTRL,X
LDA #DUMMY
STA DATA,X
LDY #0
@LOOP1: LDA DATA,X ; read data from card
STA (BUFFER),Y
INY
BNE @LOOP1
INC BUFFER+1 ; inc msb on page boundary
@LOOP2: LDA DATA,X
STA (BUFFER),Y
INY
BNE @LOOP2
DEC BUFFER+1
@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 #<~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 WRPROT
BCS @WPERROR ; card write protected
JSR GETBLOCK ; calc block address
LDA SS,X ; enable /CS
AND #<~SS0
STA SS,X
LDA #$58 ; send CMD24
JSR COMMAND ; send command
CMP #0
BNE @IOERROR ; check for error
LDA #DUMMY
STA DATA,X ; send dummy
LDA #$FE
STA DATA,X ; send data token
LDY #0
@LOOP1: LDA (BUFFER),Y
STA DATA,X
INY
BNE @LOOP1
INC BUFFER+1
@LOOP2: LDA (BUFFER),Y
STA DATA,X
INY
BNE @LOOP2
DEC BUFFER+1
@CRC: LDA #DUMMY
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
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