*===================================================================* * * * Example program demonstrating the various methods of talking to * * the SCRAM 500 device driver. * * * * Both standard and SCSI-Direct methods are demonstrated. * * * * The code is verbosely commented to make it simple to understand * * but some knowledge of 68000 assembler programming on the part of * * the reader is assumed. * * * * All code by Will McGovern. (yes, I wrote the driver as well !!) * * * * BLATENT AD ==> For a custom written driver for your hardware, * * send inquiries to : * * * * Will McGovern * * PO Box 247, * * NEW LABTON, * * NSW 2289 * * AUSTRALIA * * * * The code is written to be assembled with Macro68 from DigiSoft * * but can be converted to other formats with ease. Any Macro68 * * specific directives are explained. * * * * The 2.0 include files are used for all symbols and equates. * * * * THIS CODE IS COMPLETELY PUBLIC DOMAIN. USE IT HOWEVER YOU WANT !! * *===================================================================* Macro68 assembler directives mc68000 ;68000 mode strict ;strict syntax mode exeobj ;executable object file objfile 'example' ;object filename SYS : Call system vector macro sys macro jsr(_LVO\1,a6) endm *------------------------------------------------------------------ EXAMPLE_UNIT equ 0 ;scsi unit to talk to BLOCK_SIZE equ $200 ;size of 512 byte block MAXAUTO_SIZE equ $fe ;maximum autosense size MAXINQUIRY_SIZE equ $fe ;maximum # of inquiry bytes *------------------------------------------------------------------ section excode,code Find this task and see if we started from workbench or from a CLI start movea.l (4).w,a6 ;exec library base suba.l a1,a1 ;this task sys FindTask ;find this task movea.l d0,a4 ;save task pointer tst.l (pr_CLI,a4) ;did we come from a CLI ? bne.s clistartup ;branch if CLI entry Discard the workbench startup msg lea (pr_MsgPort,a4),a0 ;this task's message port sys WaitPort ;wait for WB startup message lea (pr_MsgPort,a4),a0 ;this task's message port sys GetMsg ;fetch the startup message Initialise a message port (MP) for use with my IORequest structure clistartup movea.l #mymp,a2 ;my message port move.l a4,(MP_SIGTASK,a2) ;save pointer to this task moveq #-1,d0 ;any signal will do sys AllocSignal ;allocate a signal for MP move.b d0,(MP_SIGBIT,a2) ;save signal # in MP bmi nosignal ;branch if error movea.l a2,a1 ;copy MP pointer sys AddPort ;add my MP to the system Open scram.device for EXAMPLEUNIT movea.l #scramname,a0 ;scram.device name movea.l #myior,a1 ;my IORequest structure move.l a2,(MN_REPLYPORT,a1) ;init MP pointer in IOR moveq #EXAMPLE_UNIT,d0 ;scsi unit to talk to moveq #0,d1 ;no flags sys OpenDevice ;open scram.device tst.l d0 ;any errors ? bne.b noscramdevice ;branch if error * Now we can talk to the scram.device through the standard * device commands such as CMD_READ or use the HD_SCSICMD command * for SCSI-Direct mode. Here are some examples of normal and SCSI-Direct mode access. Read block 0 from the unit into blockbuffer using CMD_READ command movea.l #myior,a1 ;IORequest pointer move.w #CMD_READ,(IO_COMMAND,a1) ;CMD_READ command move.l #blockbuffer,(IO_DATA,a1) ;buffer for data clr.l (IO_OFFSET,a1) ;block 0 move.l #BLOCK_SIZE,(IO_LENGTH,a1) ;one block to read sys DoIO ;read the block tst.b d0 ;any error ? bne.b cmdreaderror ;error if d0 not zero Now do the same as above in SCSI-Direct mode movea.l #myior,a1 ;IORequest pointer move.w #HD_SCSICMD,(IO_COMMAND,a1) ;CMD_READ command move.l #scsireadcmd,(IO_DATA,a1) ;pointer to SCSICmd sys DoIO ;read the block tst.b d0 ;any error ? bne.b scsireaderror ;error if d0 not zero Perform a SCSI INQUIRY command on the EXAMPLE_UNIT movea.l #myior,a1 ;IORequest pointer move.w #HD_SCSICMD,(IO_COMMAND,a1) ;HD_SCSICMD command move.l #scsiinquirycmd,(IO_DATA,a1) ;pointer to SCSICmd sys DoIO ;perform inquiry tst.b d0 ;any error ? beq.b exitexample ;error if d0 not zero This is where an error handler would be placed if this was serious code cmdreaderror: scsireaderror nop Clean up our mess and return to DOS exitexample movea.l #myior,a1 ;pointer to my IORequest sys CloseDevice ;close scram.device noscramdevice movea.l #mymp,a1 ;pointer to my MP sys RemPort ;remove my message port moveq #0,d0 ;prepare D0 for byte load move.b (mymp+MP_SIGBIT),d0 ;get signal # we allocated sys FreeSignal ;free the allocated signal nosignal moveq #0,d0 ;clear return code rts ;return to DOS *-------------------------------------------------------------------- section exdata,data Note: The SCSICmd structure used in this example did not appear in the early 1.3 include files in its entirety. C= omitted the autosense information. See the 2.0 include file "devices/scsidisk.i" for a full description of the SCSI-Direct protocol. Also note that the SCSIF_AUTOSENSE (4 byte sense length) has become SCSIF_OLDAUTOSENSE in the 2.0 implementation. The new SCSIF_AUTOSENSE supports sense data lengths of 4 to 255 bytes. The sense length is specified in scsi_SenseLength field. The SCSIF_READ/SCSIF_WRITE flags are NOT required by the scram.device as the data direction is determined automatically by the driver. SCSICmd structure for reading block 0 scsireadcmd dc.l blockbuffer ;data buffer address dc.l BLOCK_SIZE ;number of bytes to read dc.l 0 ;actual bytes read dc.l readcmd ;pointer to scsi CDB dc.w 10 ;# of command bytes dc.w 0 ;actual cmd bytes sent dc.b SCSIF_AUTOSENSE ;automatic sense dc.b 0 ;status byte dc.l sensebuffer ;buffer for sense data dc.w MAXAUTO_SIZE ;size of my sense buffer dc.w 0 ;actual sense bytes read SCSICmd structure for an INQUIRY command scsiinquirycmd dc.l inquirybuffer ;data buffer address dc.l MAXINQUIRY_SIZE ;number of bytes to read dc.l 0 ;actual bytes read dc.l inquirycmd ;pointer to scsi CDB dc.w 6 ;# of command bytes dc.w 0 ;actual cmd bytes sent dc.b SCSIF_AUTOSENSE ;automatic sense dc.b 0 ;status byte dc.l sensebuffer ;buffer for sense data dc.w MAXAUTO_SIZE ;size of my sense buffer dc.w 0 ;actual sense bytes read * Here are the actual command desciptor blocks (CDB's) sent to the * selected scsi unit. * * For more information on these consult the SCSI specifications or the * manual for your scsi device. readcmd dc.w $2800,$0000,$0000,$0000,$0100 ;extended read inquirycmd dc.w $1200,$0000,MAXINQUIRY_SIZE<<8 Text and byte data scramname cstr 'scram.device' ;null terminated name even *-------------------------------------------------------------------- section exbss,data mymp ds.b MP_SIZE ;my message port structure even myior ds.b IOSTD_SIZE ;my IORequest structure even inquirybuffer ds.b MAXINQUIRY_SIZE ;inquiry data buffer even sensebuffer ds.b MAXAUTO_SIZE ;autosense data buffer even blockbuffer ds.b BLOCK_SIZE ;block data buffer even *-------------------------------------------------------------------- end