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commit new code snippet for master-luke to load RomWBW style

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doug 13 years ago
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c9427fbe6b
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  1. 112
      branches/s100/Source/btromwbw.inc

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branches/s100/Source/btromwbw.inc
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; btromwbw.inc 2/17/2013 dwg - boot up CP/M, RomWBW Style ;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Unlike the Monahan style of booting, the RomWBW loading ;
; is performed by reading in the metadata sector and using ;
; the three words at the end of the sector to determine the ;
; loading address and starting location. ;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;-------------- BOOT UP CPM FROM HARD DISK ON S100COMPUTERS IDR BOARD ----------------
;BOOT UP THE 8255/IDE Board HARD DISK/Flash Memory Card
;NOTE CODE IS ALL HERE IN CASE A 2716 IS USED
HBOOTWBW:
POP HL ;CLEAN UP STACK
CALL INITILIZE_IDE_BOARD ;Initilze the 8255 and drive (again just in case)
LD D,11100000B ;Data for IDE SDH reg (512bytes, LBA mode,single drive)
LD E,REGshd ;00001110,(0EH) CS0,A2,A1,
CALL IDEwr8D ;Write byte to select the MASTER device
LD B,0FFH ;Delay time to allow a Hard Disk to get up to speed
WaitInitX:
LD E,REGstatus ;Get status after initilization
CALL IDErd8D ;Check Status (info in [D])
BIT 7,D
JR Z,SECREAD ;Zero, so all is OK to write to drive
;Delay to allow drive to get up to speed
PUSH BC
LD BC,0FFFFH
DXLAY2X: LD D,2 ;May need to adjust delay time to allow cold drive to
DXLAY1X: DEC D ;to speed
JR NZ,DXLAY1X
DEC BC
LD A,C
OR B
JR NZ,DXLAY2X
POP BC
DJNZ WaitInitX ;If after 0FFH, 0FEH, 0FDH... 0, then drive initilization problem
IDErrorX:
LD HL,DRIVE_NR_ERR ;Drive not ready
JP ABORT_ERR_MSG
SECREADX: ;Note CPMLDR will ALWAYS be on TRK 0,SEC 1,Head 0
CALL IDEwaitnotbusy ;Make sure drive is ready
JR C,IDError ;NC if ready
LD D,1 ;Load track 0,sec 1, head 0
LD E,REGsector ;Send info to drive
CALL IDEwr8D
LD D,0 ;Send Low TRK#
LD E,REGcyLSB
CALL IDEwr8D
LD D,0 ;Send High TRK#
LD E,REGcyMSB
CALL IDEwr8D
LD D,SEC_COUNT ;Count of CPM sectors we wish to read
LD E,REGcnt
CALL IDEwr8D
LD D,CMDread ;Send read CMD
LD E,REGCMD
CALL IDEwr8D ;Send sec read CMD to drive.
CALL IDEwdrq ;Wait until it's got the data
LD HL,CPM_ADDRESS ;DMA address where the CPMLDR resides in RAM
LD B,0 ;256X2 bytes
LD C,SEC_COUNT ;Count of sectors X 512
MoreRD16X:
LD A,REGdata ;REG regsiter address
OUT (IDECport),A
OR IDErdline ;08H+40H, Pulse RD line
OUT (IDECport),A
IN A,(IDEAport) ;read the LOWER byte
LD (HL),A
INC HL
IN A,(IDEBport) ;read the UPPER byte
LD (HL),A
INC HL
LD A,REGdata ;Deassert RD line
OUT (IDECport),A
DJNZ MoreRD16X
DEC C
JR NZ,MoreRD16X
LD E,REGstatus ;Check the R/W status when done
CALL IDErd8D
BIT 0,D
JR NZ,IDEerr1 ;Z if no errors
LD HL,STARTCPM
LD A,(HL)
CP 31H ;EXPECT TO HAVE 31H @80H IE. LD SP,80H
JP Z,STARTCPM ;AS THE FIRST INSTRUCTION. IF OK JP to 100H in RAM
JP ERR_LD1 ;Boot Sector Data incorrect
IDEerr1X:
LD HL,IDE_RW_ERROR ;Drive R/W Error
JP ABORT_ERR_MSG
;;;;;;;;;;;;;;;;;;;;;;
; eof - btromwbw.inc ;
;;;;;;;;;;;;;;;;;;;;;;
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