Subversion Repositories System09

*
** FLEX 9 COMPACT FLASH DISK DRIVERS
*
* FOR SYS09BUG 1.2 ON THE BURCHED B5-X300
* WITH I/O MAPPED AT $XE000
* AND ROM MAPPED AT $XF000
* THE BURCHED B5-X300 HAS 256KBYTES OF SRAM
* THE FIRST 64K IS USED BY FLEX,
* THE SECOND 192K MAY BE USED AS A RAM DISK
*
*
IMASK  EQU $10     IRQ MASK CC
FMASK  EQU $40     FIRQ MASK CC
DATREG EQU $FFF0   DAT REGISTERS
*
CF_BASE    EQU $E040
CF_DATA    EQU CF_BASE+0
CF_ERROR   EQU CF_BASE+1 ; read error
CF_FEATURE EQU CF_BASE+1 ; write feature
CF_SECCNT  EQU CF_BASE+2
CF_SECNUM  EQU CF_BASE+3
CF_CYLLO   EQU CF_BASE+4
CF_CYLHI   EQU CF_BASE+5
CF_HEAD    EQU CF_BASE+6
CF_STATUS  EQU CF_BASE+7 ; read status
CF_COMAND  EQU CF_BASE+7 ; write command
*
* Command Equates
*
CMDREAD    EQU $20 ; Read Single sector
CMDWRITE   EQU $30 ; Write Single sector
CMDFEATURE EQU $EF
FEAT8BIT   EQU $01 ; enable 8 bit transfers
HEADLBA    EQU $E0
*
* Status bit equates
*
BSY        EQU $80
DRDY       EQU $40
DRQ        EQU $08
ERR        EQU $01
       ORG   $DE00
*  
* DISK DRIVER JUMP TABLE
*
READ   JMP   READSC
WRITE  JMP   WRITSC
VERIFY JMP   BUSY
RESTOR JMP   RESTR1
DRIVE  JMP   DRVSEL
DRVRDY JMP   CHKDRV
QUICK  JMP   CHKDRV
COLDDR JMP   INITDR
WARMDR JMP   WARMD1
SEEK   JMP   SEEKTS
*
* RAM SPACE
*
DRVNUM FCB   0  
*
*
* INITIALIZE CF CARD FOR 8 BIT LBA MODE
*
INITDR BSR WAITRDY
       LDA  #HEADLBA
       STA  CF_HEAD
       LDA #FEAT8BIT
       STA CF_FEATURE
       LDA #CMDFEATURE
       STA CF_COMAND
       BRA WAITRDY
*  
* RESTORE DISK DRIVER (SEEK TRACK 00)
*  
RESTR1 BSR   DRVSEL
       CLRA           ; Track 0
       LDB   #$01     ; Sector 1
*
* Seek track and sector
* A holds track number (0 - ??)
* B holds sector number (1 - ??)
* Sector numbers starts from 1
* subtract 1 to start from sector 0 on CF
*
SEEKTS DECB
       STB  CF_SECNUM
       STA  CF_CYLLO
       LDB  DRVNUM
       STB  CF_CYLHI
       LDB  #$01
       STB  CF_SECCNT
       CLRB
WARMD1 RTS
*
* READ SECTORS FROM CF
*
*
READSC BSR  SEEKTS
       LDA  #CMDREAD ; IDE READ MULTIPLE
       STA  CF_COMAND
       BSR  WAITRDY
*
* READ LOOP
*
       CLRB
RDLP1  BSR  WAITDRQ
       LDA  CF_DATA
       STA  ,X+
       DECB
       BNE  RDLP1
*
       CLRB
RDLP2  BSR  WAITDRQ
       LDA  CF_DATA
       DECB
       BNE  RDLP2
*
       BSR  WAITRDY
       CLRB
       RTS
*  
* WRITE SECTOR TO CF
*  
WRITSC BSR  SEEKTS   ; SEEK TRACK & SECTOR
       LDA  #CMDWRITE; IDE WRITE MULTIPLE
       STA  CF_COMAND
       BSR  WAITRDY
*
* WRITE LOOP
*
       CLRB
WRTLP1 BSR  WAITDRQ
       LDA  ,X+
       STA  CF_DATA
       DECB
       BNE  WRTLP1
*
       CLRB
WRTLP2 BSR  WAITDRQ
       CLRA
       STA  CF_DATA
       DECB
       BNE WRTLP2
*
       BSR  WAITRDY
       CLRB
       RTS
*  
* CHECK FOR BUSY  
* Doubles as VERIFY
*  
BUSY   CLRB            Never busy
       RTS
*  
* DRIVE SELECT DISK DRIVER
*  
DRVSEL LDA   3,X       GET DRIVE # FROM FCB
       CMPA  #3  
       BLS   DRVS2     IF > 3, SET IT TO 0  
       CLRA  
DRVS2  STA   DRVNUM
       CLRB            ; SET Z, CLEAR C
       RTS
*  
* CHECK DRIVE READY DISK DRIVER
*  
CHKDRV LDA  3,X
       CLRB             ; CLEAR C, SET Z
       RTS  
*
* WAIT UNTIL READY
*
WAITRDY LDA  CF_STATUS
        BITA #BSY
        BNE  WAITRDY
        LDA  CF_STATUS
        BITA #DRDY
        BEQ  WAITRDY
        RTS
*
* WAIT FOR DATA REQUEST
*
WAITDRQ LDA  CF_STATUS
        BITA #DRQ
        BEQ  WAITDRQ
        RTS
*
        END