💾 Archived View for uscoffings.net › retro-computing › systems › AppleII › IDE-adapter › lwlv-src.tx… captured on 2023-03-20 at 20:01:55.
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;Prototype driver for IDE/ATA interface board ;65C02 assembly (using Procode) ;ATA PIO mode 1 protocol ;(c) 2001 stephane.guillard@steria.com ;Release 0.0.2 May-03-2001 ;############## Constant values base equ $C0F0 ;Base address for slot I/O 16 bytes (slot 7) datmsb equ base+0 ;Read / write latch MSB altern equ base+6 ;Alternate status byte (R) devctrl equ base+6 ;Device control reg (W) drivad equ base+7 ;Device selection (Master / Slave) datlsb equ base+8 error equ base+9 ;Error code feature equ base+9 seccnt equ base+10 secnr equ base+11 cyllow equ base+12 cylhig equ base+13 drhead equ base+14 status equ base+15 ;Status (R) command equ base+15 ;Commande (W) ;############## Screen holes used as RAM parameters for syscalls ph equ $47E ;Head parameter ps equ $4FE ; Sector parameter pcl equ $57E ;Cyl (lsb) parameter pch equ $5FE ;Cyl (msb) parameter ;############## Apple ROM useful routines home equ $FC58 ;Clear screen crout equ $FD8B ;Outputs a CR/LF cout equ $FDED ;Outputs reg. A as char strout equ $DB3A ;Outputs AY-pointed null-terminated string prax equ $F941 ;Outputs AX as 4 hex digits pra equ $FDDA ;Outputs A as 2 hex digits prspc equ $DB57 ;Outputs 1 space char ;############## Macros do 0 ;No code generation pr mac ;Outputs string without CR/LF phy pha ldy #>.0 lda #<.0 jsr strout pla ply eom prln mac ;Outputs string with CR/LF pr .0 jsr crout eom fin ;Revert to normal code generation ;############## Start of code org $4000 init0 jmp init ;############## Text messages secbuf ds 512 ;RAM sector buffer (1 sector = 512 bytes in ATA world) m_hello asc "A2IDE 2001 stephane.guillard@steria.com" dfb 0 m_done asc "ok" dfb 0 m_yes asc "yes" dfb 0 m_no asc "no" dfb 0 m_hd asc "Non-packet IDE HD signature..." dfb 0 m_reset asc "Init HD� " dfb 0 m_qry asc "Get HD info..." dfb 0 m_name asc "Name.....:" dfb 0 m_firm asc "Firmware.:" dfb 0 m_ser asc "Serial #.:" dfb 0 m_cyl asc "Cylinders:&H" dfb 0 m_head asc "Heads....:&H" dfb 0 m_sec asc "Sectors..:&H" dfb 0 m_lba asc "Lba......:" dfb 0 m_mbr asc "Read MBR..." dfb 0 m_chk asc "MBR signature..." dfb 0 m_part asc "Partition #" dfb 0 m_undef asc "undef'd" dfb 0 m_act asc ">Active:" dfb 0 m_start asc ">CHS start:" dfb 0 m_end asc ", end :" dfb 0 m_type asc ", type " dfb 0 m_res asc ">Resvd secs:" dfb 0 m_seccnt asc ">Total secs:" dfb 0 m_rdy asc "Boot sector in secbuf at $" dfb 0 m_rdsect asc "RDSect() syscall at $" dfb 0 ;############## init() : main init routine init jsr home ;Clear screen prln m_hello jsr hdinit ;Reset HD bcs done jsr hdqry ;Query and display HD info bcs done jsr hdmbr ;Analyze MBR and find 1st partition boot sector (leave CHS in RAM parameters) bcs done jsr rdsect ;Read 1st partition boot sector into RAM sector D42buffer bcs done pr m_rdy ;Print sector buffer address (for later use in other sw) ldx #<secbuf lda #>secbuf jsr prax jsr crout pr m_rdsect ;Print RDSect() syscall address (for later use in other sw) ldx #<rdsect lda #>rdsect jsr prax jsr crout done clc rts ;End ;############## hdinit() : check IDE HDD signature and reset disk signok prln m_no sec rts hdinit pha ;Init master IDE peripheral stz datmsb ;Clear interface MSB register (we are going to make a few 8 bit transfers) stz drhead ;Select master pr m_hd ;Check IDE non packet signature : seccnt=secnr=1, lda #$1 ;cyllow=cylhig=0 cmp seccnt ;If signature is different then peripheral may be an ATAPI (ATA w/packet bne signok ;interface, like CD) or nothing cmp secnr bne signok lda #$0 cmp cyllow bne signok cmp cylhig bne signok prln m_yes pr m_reset lda #$06 ;Start reset, no interrupts sta devctrl lda #$02 ;Stop reset, no interrupts sta devctrl jsr waitBSY ;Wait for BUSY bit to go away prln m_done pla clc rts ;############## hdmbr() ; read disk Master Boot Record, check it and analyze partition entries hdmbr pha ;Analyze MBR and find 1st partition boot sector (leave CHS in RAM parameters) phx phy pr m_mbr ;MBR = sector C=0, H=0, S=1 lda #$1 sta ps stz ph stz pcl stz pch jsr rdsect ;Read sector prln m_done pr m_chk ;Check signature MBR : offset 1FE=$55AA lda secbuf+$1FE cmp #$55 beq ]55ok jmp ]signok ]55ok lda secbuf+$1FF cmp #$AA beq ]AAok ]signok prln m_no sec rts ]AAok prln m_done ;Scan the 4 partition entries of MBR (starts at secbuf+446) ldy #$0 ;Y=offset beginning part from (secbuf + 446) (Y may be 0, 16, 32, 48) ]nextprt pr m_part ;Loop for 4 partition entries tya ;Store A in Y, and then A <- D272A/16 phy lsr lsr lsr lsr jsr pra ;Output current partition number (may be 0, 1, 2, 3) pr m_type ;Output partition type (as hex) ply phy lda secbuf+446+4,y bne ]defined ;If partition type is null then partition is not defined prln m_undef jmp ]undef ]defined jsr pra jsr crout pr m_act ;Output partition active flag Y/N ply phy lda secbuf+446+0,y cmp #$80 beq ]active prln m_no jmp ]chs ]active prln m_yes ]chs pr m_start ;Output start / End CHS (note that start CHS is the boot sector of the partition) ply phy lda secbuf+446+2+1,y ;A - Extract cyl# (10 bit) into AX and #$C0 ;A1 - Extract cyl# MSB which is in the 2 upper bits of sector#, into A lsr lsr lsr lsr lsr lsr ldx secbuf+446+2,y ;A2 - Extract cyl# LSB into X sta pch ;Store cyl# in RAM parameters for later RDSect() call by init() (to read in boot sector) stx pcl jsr prax jsr prspc ply phy lda secbuf+446+1,y ;B - Extract head# sta ph ;Store head# in RAM parameters for later RDSect() call by init() (to read in boot sector) jsr pra jsr prspc ply phy lda secbuf+446+2+1,y ;C - Extract sector# (and mask out the 2 upper bits which are part of cyl#, see A above) and #$3F sta ps ;Store sector# in RAM parameters for later RDSect() call by init() (to read in boot sector) jsr pra pr m_end ;Do the same for partition end CHS ply phy lda secbuf+446+6+1,y ;MSB C and #$C0 lsr lsr lsr lsr lsr lsr ldx secbuf+446+6,y ;LSB C jsr prax jsr prspc ply phy lda secbuf+446+5,y ;H jsr pra jsr prspc ply phy lda secbuf+446+6+1,y ;S and #$3F jsr pra jsr crout pr m_res ;Reserved sectors (not implemented yet) jsr crout pr m_seccnt ;Total sectors (not implemented yet) jsr crout ]undef ply ;Next partition : Y <- Y + 16 tya clc adc #16 tay cmp #64 beq ]done jmp ]nextprt ]done ply plx pla clc rts ;############## hdqry() : inquiry disk properties and display them hdqry pha phx pr m_qry stz datmsb lda #$EC ;Send ATA Inquiry command sta command jsr waitBSY jsr waitDATA jsr rd512byt prln m_done pr m_name ;Output disk name ldx #54 ]nextc lda secbuf,x jsr cout inx cpx #94 bne ]nextc jsr crout pr m_firm ;Output disk firmware rev. ldx #46 ]nextf lda secbuf,x jsr cout inx cpx #54 bne ]nextf jsr crout pr m_ser ;Output disk serial # ldx #20 ]nexts lda secbuf,x jsr cout inx cpx #40 bne ]nexts jsr crout pr m_cyl ;Output cylinder count lda secbuf+2 ldx secbuf+3 jsr prax jsr crout pr m_head ;Output head count lda secbuf+6 ldx secbuf+7 jsr prax jsr crout pr m_sec ;Output sector per track count lda secbuf+12 ldx secbuf+13 jsr prax jsr crout pr m_lba ;Output LBA accepted flag (yes / no) lda secbuf+98 bit #8 beq ]nolba prln m_yes jmp ]done ]nolba prln m_no ]done plx pla clc rts ;############## rdsect() : read a sector pointed by pch/pcl, ph, ps into secbuf rdsect pha lda #$1 sta seccnt ;We want to read 1 sector (multiple sector transfer is also possible) lda ps sta secnr ;Sector # in track lda pcl sta cyllow ;Cylinder # LSB lda pch sta cylhig ;Cylinder # MSB lda ph sta drhead ;Head # stz datmsb lda #$20 sta command ;Send ATA Read Sector command jsr waitBSY ;Wait for BUSY to go away jsr waitDATA ;Wait for DRQ to come (DRQ is Data ReQuest) jsr rd256wrd ;Read 256 16 bit words into RAM sector buffer pla clc rts ;############## rd256wrd() : read 256 16 bit words into RAM sector buffer rd256wrd phx ;The trick is simple : we read the interface LSB first. pha ;This latches the drive's MSB at the same time into the interface MSB latch. ldx #$0 ;Then we read the interface's MSB latch and we have read the full 16 bits from the drive. ]next1 lda datlsb sta secbuf,X lda datmsb sta secbuf+1,X inx inx bne ]next1 ]next2 lda datlsb sta secbuf+$100,X lda datmsb sta secbuf+$101,X inx inx bne ]next2 pla plx rts ;############## rd512byt() : read 512 8 bit words into RAM sector buffer rd512byt phx ;Same as above. But as this is a 8 bit transfer, the order of the bytes come reversed. pha ldx #$0 ]next1 lda datlsb sta secbuf+1,X lda datmsb sta secbuf,X inx inx bne ]next1 ]next2 lda datlsb sta secbuf+$101,X lda datmsb sta secbuf+$100,X inx inx bne ]next2 pla plx rts ;############## waitDATA() : wait for DRQ bit to come waitDATA pha ]wait lda status bit #$8 ;Loop until DRQ == 1 beq ]wait pla rts ;############## waitBSY() : wait for BUSY bit to go waitBSY pha ]wait lda status bit #$80 ;Loop until BUSY == 0 bne ]wait pla rts ;############## dumpsec() : dump current sector in secbuf to screen (first as chars then as hex) dumpsec pha phx phy ldx #$0 ]next1 lda secbuf,x cmp #$20 bmi ]notasc1 cmp #$7E bmi ]done1 ]notasc1 lda #32 ]done1 jsr cout inx bne ]next1 ]next2 lda secbuf+$100,x cmp #$20 bmi ]notasc2 cmp #$7E bmi ]done2 ]notasc2 lda #32 ]done2 jsr cout inx bne ]next2 jsr crout ldy #0 ]next3 lda secbuf+1,y tax lda secbuf,y phy jsr prax ply iny iny bne ]next3 ]next4 lda secbuf+$101,y tax lda secbuf+$100,y phy jsr prax ply iny iny bne ]next4 jsr crout ply plx pla rts