mirror of https://github.com/wwarthen/RomWBW.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
318 lines
12 KiB
318 lines
12 KiB
;::::::::::::::::::::::::::::::::::::::::::::******************************
|
|
; Floppy Disk Routines ***** Hardware Dependent *****
|
|
; - Retro-Brew Hardware with HBIOS - ******************************
|
|
;
|
|
; 1.4 - 27 Mar 14 - Initial N8VEM test release WW+LN
|
|
; 1.3 - 26 Aug 01 - Cleaned up for GPL Release. HFB
|
|
; 1.2c- 12 May 97 - Cleaned up source, modified STSIZE Code (again). HFB
|
|
; 1.2b- 22 Apr 97 - Changed 5.25" Hi/Lo Speed controls. HFB
|
|
; 1.0a- 23 Mar 97 - (test) fixes. HFB
|
|
; 1.0 - 13 Aug 96 - Initial Release for P112 from YASMIO. HFB
|
|
;::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
; Floppy Units are accessed on Retro-Brew systems using HBIOS function
|
|
; calls. These functions include read, write, status and media type.
|
|
; For 3.5" drive there are two media types. For 5.25" drive two media
|
|
; types are supported, while for 8" drives one type is supported.
|
|
; Only high density is supported on 3.5" drives either single or double
|
|
; sided. For 5.25" drive either double or high density is supported on
|
|
; double sided disks. Only double density double sided 8" disks are
|
|
; supported. Many BPBIOS floppy routines are stubbed such as DMA support
|
|
; and motor control since all these details are handled behind the scene by
|
|
; HBIOS. Currently HBIOS handles the head given the track and sector so
|
|
; the interface treats all floppies as single sided.
|
|
|
|
IF BANKED
|
|
COMMON /BANK2/
|
|
ELSE
|
|
CSEG
|
|
ENDIF
|
|
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
; STMODE (Function 0) - Set the FDC mode for Read/Write operations.
|
|
;
|
|
; Enter : A = Single-Density Flag (0 = Double Dens, 0FFH = Single Dens)
|
|
; Return: Nothing
|
|
; Uses : AF All other Registers Preserved/Not Affected
|
|
;
|
|
; Assumes STSIZE and STSECT called first
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
|
|
STMODE: CALL PANIC
|
|
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
; STSIZE (Function 1) - Set Drive Size (3.5", 5.25", 8"), Drive Speed
|
|
; (High/Low) Capability, and a Boolean flag for whether Motor Control is
|
|
; needed by the Drive.
|
|
;
|
|
; Enter : A = Hi Speed Flag ( 0 = Normal, 0FFH = High Speed Capable)
|
|
; D = Motor Flag (0 = No Motor Control, 0FFH = Motor needed)
|
|
; E = Drive Size (0 = Hard, 001 = 8", 010 = 5.25", 011 = 3.5")
|
|
; Return: Nothing
|
|
; Uses : AF All other Registers Preserved/Not Affected
|
|
;
|
|
; Assumes STHDRV Called Previously. Call before calling STMODE.
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
|
|
STSIZE: CALL PANIC
|
|
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
; STHDRV (Function 2) - Set Head and Drive for Disk Operations.
|
|
;
|
|
; Enter : A = Unit # in D0-D1, Head in D2
|
|
; Return: Nothing
|
|
; Uses : AF All other Registers Preserved/Not Affected
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
|
|
STHDRV: CALL PANIC
|
|
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
; STSECT (Function 3) - Set Sector Number, Sector Size and Last Sector #
|
|
;
|
|
; Enter : A = Physical Sector Number
|
|
; D = Sector Size (0=128, 1=256, 2=512, 3=1024)
|
|
; E = Last Physical Sector # on Side
|
|
; Return: Nothing
|
|
; Uses : AF All other Registers Preserved/Not Affected
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
|
|
STSECT: CALL PANIC
|
|
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
; SPEC (Function 4) - Do a Specify Command, setting Step Rate and Head
|
|
; Load/Unload Time. Values are rounded up if not even increments.
|
|
;
|
|
; Enter : A = Step Rate (in mS; Bit 7 = 1 for 8" drive
|
|
; D = Head Unload Time (in mS)
|
|
; E = Head Load Time (in mS)
|
|
; Return: Nothing
|
|
; Uses : AF All other Registers Preserved/Not Affected
|
|
;
|
|
; Assumes STSIZE called previously to set DRVSPD variable.
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
|
|
SPEC: CALL PANIC
|
|
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
; RECAL (Function 5) - Recalibrate Drive (moves heads to track 0).
|
|
;
|
|
; Enter : Nothing
|
|
; Return: A = 0 if Ok, NZ if Error. Flags reflect A
|
|
; Uses : AF All other Registers Preserved/Not Affected
|
|
;
|
|
; NOTE: BC Must be preserved by this routine.
|
|
; Assumes STHDRV, SPEC, STSIZE and STMODE called first.
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
|
|
RECAL: CALL PANIC
|
|
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
; SEEK (Function 6) - Set the Track for disk operations and seek to it.
|
|
;
|
|
; Enter : A = Desired Track Number
|
|
; D = Verify flag (0=No, FF=Yes)
|
|
; E = Double-step Flag (E <> 0 for Double-step)
|
|
; Return: A = 0, Zero Flag Set (Z) if Ok, A <> 0 Zero Clear (NZ) if Error
|
|
; Uses : AF All other Registers Preserved/Not Affected
|
|
;
|
|
; Assumes STHDRV, SPEC, STSIZE and STMODE are called first.
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
|
|
SEEK: CALL PANIC
|
|
XOR A
|
|
RET
|
|
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
; SREAD (Function 7) - Read a Sector from the Floppy Disk. The Mode,
|
|
; Head/Drive, Track, and Sector must have already been set.
|
|
;
|
|
; Enter : HL --> Read Buffer
|
|
; Return: A = 0, Zero Set (Z) if Ok, A <> 0, Zero Clear (NZ) if Error.
|
|
; Uses : AF,HL. All other Registers Preserved/Not Affected
|
|
;
|
|
; Assumes STMODE, STHDRV, STSECT, SPEC and SEEK Called First.
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
|
|
SREAD: CALL PANIC
|
|
XOR A
|
|
RET
|
|
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
; SWRITE (Function 8) - Write a Sector to the Floppy Disk. The Mode,
|
|
; Head/Drive, Track, and Sector must have already been set.
|
|
;
|
|
; Enter : HL --> Write Buffer
|
|
; Return: A = 0, Zero Flag Set (Z) if Ok, A <> 0 Zero Clear (NZ) if Errors
|
|
; Uses : AF,HL. All other registers Preserved/Not Affected.
|
|
; Assumes STMODE, STHDRV, STSECT, SPEC and SEEK Called First.
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
|
|
SWRITE: CALL PANIC
|
|
XOR A
|
|
RET
|
|
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
; READID (Function 9) - Read the first Valid Address Mark on a track.
|
|
;
|
|
; Enter : Nothing
|
|
; Return: A = 0 if Ok, NZ if Error. Flags reflect A
|
|
; Uses : AF All other Registers Preserved/Not Affected
|
|
;
|
|
; Assumes STHDRV, SPEC, STSIZE and STMODE called first.
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
|
|
READID: CALL PANIC
|
|
XOR A
|
|
RET
|
|
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
; RETDST (Function 10) - Return the status of a drive.
|
|
; This routine reports a "765" Controller type instead of actual number.
|
|
;
|
|
; Enter : Nothing
|
|
; Return: A = Status byte
|
|
; BC = 765 (FDC Controller Type)
|
|
; HL = Address of Status Byte
|
|
; Uses : AF,BC,HL All other Registers Preserved/Not Affected
|
|
;
|
|
; Assumes STHDRV called first
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
|
|
RETDST: CALL PANIC
|
|
;LD HL,ST0 ; Point to Status Byte (Reg 3 contents)
|
|
;LD A,(HL) ; fetch it
|
|
;LD BC,765 ; load Controller ID
|
|
RET
|
|
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
; FMTTRK (Function 11) - Format a complete track on one side of a Floppy
|
|
; Disk. The Mode, Head/Drive, Track, and Sector must have been set.
|
|
;
|
|
; NOTE: The contents of the Format Data Block varies between controllers,
|
|
; so RETDST should be called to determine the controller type before
|
|
; setting up data structures.
|
|
;
|
|
; Enter : D = Formatting Sctrs/Track value
|
|
; E = Formatting Gap 3 Byte Count
|
|
; HL = Pointer to Controller-dependent Format Data block
|
|
; Return: A = 0, Zero Flag Set (Z) if Ok, A <> 0 Zero Clear (NZ) if Errors
|
|
; Uses : All Primary Registers
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
|
|
FMTTRK: CALL PANIC
|
|
;XOR A
|
|
RET
|
|
|
|
;=============================================================================
|
|
; FDCMD - Send Command to FDC
|
|
; Enter: B = # of Bytes in Command, C = Command Byte
|
|
; HL -> Buffer for Read/Write Data (If Needed)
|
|
; Exit : AF = Status byte
|
|
; Uses : AF,BC
|
|
|
|
FDCMD: CALL PANIC
|
|
;LD A,(ST0) ; Else get first byte of Status
|
|
;AND 0C0H ; check for Normal termination
|
|
RET ; ..return w/Error Flags set
|
|
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
; MOTOR CONTROL. This routine performs final selection of the drive control
|
|
; latch and determines if the Motors are already spinning. If they are off
|
|
; and Motor control is needed, then the Motors are activated and the spinup
|
|
; delay time in tenths-of-seconds is performed before returning.
|
|
;
|
|
; Enter : Command byte in A
|
|
; Return: Head Delay bit set in Command in A if needed
|
|
; Uses : None. All Registers Preserved/Not Affected
|
|
|
|
MOTOR: CALL PANIC
|
|
XOR A
|
|
RET
|
|
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
; Hardware-Dependent Host Read/Write Routine linked to from FLOPPY module.
|
|
; This routine Reads/Writes data from HSTBUF trying up to MXRTRY times
|
|
; before giving up. If an error occurs after the next-to-last try, the
|
|
; heads are homed to force a re-seek.
|
|
;
|
|
; Enter: (RDOP Set for desired operation)
|
|
; Exit : A = 0, Zero Set if Ok, A <> 0, Zero Reset if Errors
|
|
; Uses : AF,HL
|
|
;
|
|
; RDOP is set to 1 for Read, 0 for Write, TTRK set with desired Track
|
|
; number, STHDRV, STSECT, STMODE, SPEC all called previously.
|
|
;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
|
|
|
FHDRW: CALL PANIC
|
|
;XOR A
|
|
RET
|
|
|
|
|
|
;- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
|
|
|
|
CSEG ;*** Remainder of Code MUST be in Main Memory ***
|
|
|
|
;========================================================================
|
|
; Reset the Floppy Disk Controller. Called from CBOOT in case of Hard
|
|
; Disk Boot which leaves the controller in a "hung" state, and locally
|
|
; if the Controller times out (often due to changing diskettes).
|
|
|
|
FDRst: CALL PANIC
|
|
RET
|
|
|
|
;========================================================================
|
|
; Motor Off routine. Called from SELFLP2 which forces
|
|
; Motors/Timer to be Off state so spinup delay is forced on next selection.
|
|
|
|
MOTOFF: CALL PANIC
|
|
ChgSpd: RET
|
|
|
|
;======================== RAM Storage Area ==============================
|
|
|
|
IF BANKED
|
|
COMMON /B2RAM/ ; If banked, Local stack in Bank
|
|
ELSE
|
|
DSEG ; ..otherwise in Data Segment
|
|
ENDIF ;
|
|
|
|
DSEG ; Place in Common memory
|
|
|
|
; NOTE: Variables listed as (** Global **) are accessed by other modules and
|
|
; MUST exist as defined.
|
|
|
|
HDR: DEFS 1 ; Head (B2), Drive (B0,1) (** Global **)
|
|
|
|
; FDC Operation Result Storage Area
|
|
|
|
;ST0: DEFS 1 ; Status Byte 0
|
|
;ST1: DEFS 1 ; Status Byte 1 (can also be PCN)
|
|
;ST2: DEFS 1 ; Status Byte 2
|
|
RC: DEFS 1 ; Track # (** Global **)
|
|
;RH: DEFS 1 ; Head # (0/1)
|
|
RR: DEFS 1 ; Sector # (** Global **)
|
|
RN: DEFS 1 ; Sector Size (** Global **)
|
|
|
|
;-->>> Do NOT re-order the following two bytes !! <<<--
|
|
|
|
;MTM: DEFS 1 ; Floppy Time down-counter
|
|
;MOTIM: DEFS 1 ; Motor On Time Counter
|
|
|
|
; DISK Subsystem Variable Storage
|
|
|
|
;FDMOT: DEFS 1 ; Motor on required flag
|
|
RDOP: DEFS 1 ; Read/write flag
|
|
;RETRYS: DEFS 1 ; Number of times to try Opns
|
|
;RWRTRY: DEFS 1 ; Number of read/write tries
|
|
;DRVSPD: DEFS 1 ; Drive Speed
|
|
;DRVSIZ: DEFS 1 ; Drive Size
|
|
STEP2: DEFS 1 ; <> 0 for Double Step (** Global **)
|
|
;MODE: DEFS 1 ; Bit 6 = 1 if MFM, 0 = FM
|
|
;ACTIVE: DEFS 1 ; Current bits written to Dev Contr Reg (DCR)
|
|
;DLYCNT: DEFS 1 ; Delay value reading Main Status Reg
|
|
;FSPT: DEFS 1 ; Format Sectors/Track value
|
|
TSBSCF: DEFS 1 ; 0=Hd always 0 (TSBSC) (** Global **)
|
|
|
|
TTRK: DEFS 1 ; Storage for Track (** Global **)
|
|
;TRKARY: DEFS 4 ; Track storage locations for four drives
|
|
|
|
;=========================== End of FDC-WW ==============================
|
|
|