v2.0/source/DEVSYM.ASM

   1 SUBTTL DEVICE TABLE AND SRH DEFINITION
   2 PAGE
   3 ; The device table list has the form:
   4 SYSDEV  STRUC
   5 SDEVNEXT        DD      ?       ;Pointer to next device header
   6 SDEVATT         DW      ?       ;Attributes of the device
   7 SDEVSTRAT       DW      ?       ;Strategy entry point
   8 SDEVINT         DW      ?       ;Interrupt entry point
   9 SDEVNAME        DB      8 DUP (?) ;Name of device (only first byte used for block)
  10 SYSDEV  ENDS
  11
  12 ;Attribute bit masks
  13 DEVTYP  EQU     8000H           ;Bit 15 - 1  if Char, 0 if block
  14 DEVIOCTL EQU    4000H           ;Bit 14 - CONTROL mode bit
  15 ISFATBYDEV EQU  2000H           ;Bit 13 - Device uses FAT ID bytes, comp media.
  16 ISCIN   EQU     0001H           ;Bit 0 - This device is the console input.
  17 ISCOUT  EQU     0002H           ;Bit 1 - This device is the console output.
  18 ISNULL  EQU     0004H           ;Bit 2 - This device is the null device.
  19 ISCLOCK EQU     0008H           ;Bit 3 - This device is the clock device.
  20 ISIBM   EQU     0010H           ;Bit 4 - This device is special
  21
  22 ;Static Reguest Header
  23 SRHEAD  STRUC
  24 REQLEN  DB      ?               ;Length in bytes of request block
  25 REQUNIT DB      ?               ;Device unit number
  26 REQFUNC DB      ?               ;Type of request
  27 REQSTAT DW      ?               ;Status Word
  28         DB      8 DUP(?)        ;Reserved for queue links
  29 SRHEAD  ENDS
  30
  31 ;Status word masks
  32 STERR   EQU     8000H           ;Bit 15 - Error
  33 STBUI   EQU     0200H           ;Bit 9 - Buisy
  34 STDON   EQU     0100H           ;Bit 8 - Done
  35 STECODE EQU     00FFH           ;Error code
  36 WRECODE EQU     0
  37
  38 ;Function codes
  39 DEVINIT EQU     0               ;Initialization
  40 DINITHL EQU     26              ;Size of init header
  41 DEVMDCH EQU     1               ;Media check
  42 DMEDHL  EQU     15              ;Size of media check header
  43 DEVBPB  EQU     2               ;Get BPB
  44 DEVRDIOCTL EQU  3               ;IOCTL read
  45 DBPBHL  EQU     22              ;Size of Get BPB header
  46 DEVRD   EQU     4               ;Read
  47 DRDWRHL EQU     22              ;Size of RD/WR header
  48 DEVRDND EQU     5               ;Non destructive read no wait (character devs)
  49 DRDNDHL EQU     14              ;Size of non destructive read header
  50 DEVIST  EQU     6               ;Input status
  51 DSTATHL EQU     13              ;Size of status header
  52 DEVIFL  EQU     7               ;Input flush
  53 DFLSHL  EQU     15              ;Size of flush header
  54 DEVWRT  EQU     8               ;Write
  55 DEVWRTV EQU     9               ;Write with verify
  56 DEVOST  EQU     10              ;Output status
  57 DEVOFL  EQU     11              ;Output flush
  58 DEVWRIOCTL EQU  12              ;IOCTL write
  59