10REM > IDEPatch 1.19
   20REM Modified for BBC Plus and BBC Model B fitted with Acorn WD1770 controller
   30REM Patch BBC Model B ADFS-1.31E00 ROM to access IDE devices:REM CHANGED
   40REM v1.10 Trial version, incorporates context preservation on Ctrl-Break
   50REM v1.11 Verified with real hardware
   60REM v1.13 Stack params, do one sector at a time
   70REM v1.14 IDE transfers done twice to avoid DRQ bug, Tube works
   80REM v1.15 SetGeo uses correct drive, errors translated
   90REM v1.16 Automatically finds Library directory
  100REM v1.17 Two drives per device, no wait for spin-up on power-on
  105REM v1.18 Removed pain-in-the-arse context preservation on Ctrl-Break
  107REM v1.19 Adapted Acorn ADFS-1.31E00 ROM for models with =>16 KByte Sideways RAM
  110:
  120DIM mcode% &3FFF:ver$="1.32":REM CHANGED
  130INPUT"ADFS-1.31E00 ROM image: "file$:REM CHANGED
  140OSCLI"Load "+file$+" "+STR$~mcode%
  150IF mcode%!&16<>&31332E31:PRINT"Not ADFS-1.31E00 ROM":END:REM CHANGED
  160DEF FNorg(A%,B%):P%=A%:O%=A%-&8000+mcode%:=P*3+4
  170:
  180FOR P=0 TO 1
  190[OPT FNorg(&8008,-1)
  200EQUB EVAL("&"+MID$(ver$,3))     :\ New version byte
  210]
  220[OPT FNorg(&8016,-1)
  230EQUS LEFT$(ver$,1)+MID$(ver$,2) :\ New version string  :\ CHANGED
  240]
  242[OPT FNorg(&8033,-1)
  243JSR &8F80:RTS       :\ A Kludge to prevent the untraceable ???? NoRAM message.
  244EQUB &7F:EQUS "NoRA":EQUB &CD
  245]
  250[OPT FNorg(&8085,-1)            :\ &8057 CHANGED FROM &8070
  260LDA &FC47:STA &CC:LDA &FC47     :\ Read IDE status byte
  270]
  280[OPT FNorg(&8093,-1)            :\ &8065 CHANGED FROM &807E
  290RTS:NOP:NOP:NOP                 :\ Remove SCSI code
  300NOP
  310.ReadBreak
  320NOP:NOP:NOP:NOP:NOP:NOP  :\ JSR &9A88 AND #&01 RTS  :\ CHANGED :\ Power-on Reset?
  330NOP:NOP
  340.WaitForData
  350LDA &FC47:AND #8:BEQ WaitForData:\ Loop until data ready :\ BIT #8
  360RTS
  370:
  380.MountCheck
  390JSR &9A1E:JMP &9569 :\ Do *MOUNT, reselect ADFS JSR &A15E\JMP &9B38 FROM &A19E\&9B4A
  400:
  410\ next=&8080                     :\ Changed from &8099
  420]
  430[OPT FNorg(&8123,-1)            :\ Access hard drive :\ &80F6 CHANGED FROM &811A
  440LDY #0
  450NOP
  460]
  470[OPT FNorg(&8129,&818A)  :\ 8114 CHANGED FROM &8137,&81AD Loop Point
  480LDY #5:JMP BYE
  490.SetCommand1
  500PHP:JMP SetCommand
  510NOP
  520NOP      
  530NOP
  540NOP
  550:
  555.CommandSaveLp1
  560LDA &B0:PHA:LDA &B1:PHA
  570JSR UpdateDrive                 :\ Merge drive
  580STA &B0:STY &B1                 :\ Point to block in RAM
  590PHP:JSR SetGeometry:PLP         :\ Set shape to c*4*64
  600.CommandLoop
  610LDX #2:.Twice                   :\ First pass to seek sector
  620BIT &CD:BVC CommandStart        :\ Accessing I/O memory
  630PHP:TXA:PHA:LDX #&27:LDY #&B2:LDA #0:\ Point to address block    :\ CHANGED PHX
  640ROL A:EOR #1:JSR SetTubeAction+1:PLA:TAX:PLP :\ Set Tube action :\ FROM &8213 PLX
  650.CommandStart                   :\ C=R/W, &B0/1=>block
  660JSR SetSector                   :\ Set sector, count, command
  670.TransferLoop
  680JSR WaitForData:AND #&21:BNE TransDone
  690BIT &CD:BVS TransTube:BCC IORead
  700.IOWrite  :LDA (&80),Y:STA &FC40:JMP TransferByte        :\ BRA TransferByte
  710.IORead   :LDA &FC40:STA (&80),Y:JMP TransferByte        :\ BRA TransferByte
  720.TransTube:BCC TubeRead
  730.TubeWrite:LDA &FEE5:STA &FC40:JMP TransferByte        :\ BRA TransferByte
  740.TubeRead :LDA &FC40:STA &FEE5:JMP TransferByte        :\ BRA TransferByte
  750.CommandLoop1
  755JMP CommandLoop
  760\ next=&8197                     &818A CHANGED FROM &81AD YES ENTRY POINT!!!!!
  770]
  780[OPT FNorg(&8197,&81EF)         :\ Transfer completed  :\ &818A CHANGED from &81AD
  790.CommandDone
  800JSR GetResult                   :\ Get IDE result
  810.CommandExit
  820PHA:JSR &8072:PLA               :\ Release Tube  :\ &8043 CHANGED from &803A
  830LDX &B0:LDY &B1:AND #&7F        :\ Restore registers
  840RTS
  850:
  860.TransferByte
  870INY:BNE TransferLoop            :\ Loop for 256 bytes
  880DEX:BNE Twice:INC &81           :\ Second pass to do real transfer
  890LDA &FC47:AND #&21:BNE TransDone:\ Error occured
  900INC &B228:BNE TubeAddr          :\ Increment Tube address  :\ CHANGED &1028
  910INC &B229:BNE TubeAddr:INC &B22A                           :\ CHANGED &1029 &102A                      
  920.TubeAddr
  930INC &87:BNE TransCount          :\ Increment sector
  940INC &86:BNE TransCount:INC &85
  950.TransCount
  960DEC &88:BNE CommandLoop1        :\ Loop for all sectors
  970                                :\ Done, check for errors
  980:
  990.TransDone
 1000PLA:STA &B1:PLA:STA &B0:INY     :\ Restore pointer
 1010.CommandRestore                 :\ Restore memory
 1020PLA:STA &7F,Y:INY:CPY #10:BNE CommandRestore
 1030BEQ CommandDone                 :\ Jump to get result BRA CommandDone                 
 1040:
 1050.SetGeometry
 1060JSR WaitNotBusy
 1070LDA #64:STA &FC42:STA &FC43             :\ 64 sectors per track
 1080LDY #6:LDA (&B0),Y:LSR A:LSR A:ORA #3   :\ Get drive number
 1090JSR SetDriveA:LDA #&91:BNE SetCmd       :\ 4 heads per cylinder
 1100.SetTubeAction 
 1110\ next=&81FC                             CHANGED 81EF from &8212 
 1120]:REM                                    &8201=Entry Point
 1130[OPT FNorg(&8205,&8282)                 :\ CHANGED &81FC from &821F
 1140.SetSector
 1150PHP:JSR WaitNotBusy                     :\ Save CC/CS Read/Write
 1160LDY #8:LDA #1:STA &FC42                 :\ One sector
 1170CLC:LDA (&B0),Y:AND #63:ADC #1:STA &FC43:\ Set sector b0-b5
 1180DEY:LDA (&B0),Y:ADC #0:STA &FC44        :\ Set sector b8-b15
 1190DEY:LDA (&B0),Y:JSR SetCylinder         :\ Set sector b16-b21
 1200INY:INY:EOR (&B0),Y:AND #2:EOR (&B0),Y  :\ Merge Drive and Head
 1210JSR SetDrive:DEY:DEY:DEY:LDA (&B0),Y    :\ Get command &08 or &0A
 1220.SetCommand
 1230AND #2:PHA:EOR #2:LSR A:LSR A           :\ Copy ~b1 into Cy
 1240PLA:ASL A:ASL A:ASL A:ORA #&20          :\ Translate CS->&20 or CC->&30
 1250LDY #0:PLP:.SetCmd:STA &FC47:RTS        :\ Set command &08 or &0A
 1260:
 1270.SetDrive
 1280ROL A:ROL A:ROL A                       :\ Move into position
 1290.SetDriveA
 1300AND #&13:STA &FC46:RTS                  :\ Set device + sector b6-b7
 1310:
 1320.SetCylinder
 1330PHA:AND #&3F:ADC #0:STA &FC45           :\ Set sector b16-b21
 1340PLA:ROL A:ROL A:ROL A:ROL A:RTS         :\ Get Drive 0-1/2-3 into b1
 1350:
 1360.SetRandom
 1370JSR SetCylinder                         :\ Set sector b16-b21
 1380EOR &B201,X:AND #&02:EOR &B201,X        :\ Merge Drive and Head  :\ CHANGED
 1390JSR SetDrive:PLA:JMP SetCommand1        :\ Set device and command BRA SetCommand
 1400:
 1410.GetResult
 1420LDA &FC47:AND #&21:BEQ GetResOk         :\ Get IDE result
 1430ORA &FC41:LDX #&FF                      :\ Get IDE error code
 1440.GetResLp
 1450INX:ROR A:BCC GetResLp:LDA ResultCodes,X  :\ Translate result code
 1460.GetResOk
 1470RTS
 1480NOP:NOP:NOP
 1490\ next=&828C - Entry Point       :\&8282 CHANGED from &82A5 - Entry Point
 1500]
 1510[OPT FNorg(&8304,-1)             :\ &8305 CHANGED from &8328
 1520LDA &CD:AND #&FE:STA &CD         :\ Fake that ensuring has completed
 1530RTS:NOP:NOP:NOP
 1540]:REM next=&830E
 1550[OPT FNorg(&830E,&831B)          :\ &830F CHANGED from &8332
 1560.WaitNotBusy
 1570PHP
 1573.IDEstatus
 1576JSR &8084                        :\ Get IDE status  :\ &8056 CHANGED from &806F
 1580AND #&C0:CMP #&40:BNE IDEstatus  :\ Wait for IDE not busy and ready
 1590PLP:RTS
 1600\ next=&831A                     :\ 11 spare bytes 831B
 1610]
 1620[OPT FNorg(&897D,-1)             :\ Load a partial sector :\ &8B72 CHANGED from &8B7F
 1640TXA:PHA:JSR SetGeometry:JSR SetSector:\ Pass sector address to IDE  PHX
 1660PLA:TAX:NOP                                                       :\PLX
 1670]:REM  next=&8988                :\ next=&8B7f
 1680[OPT FNorg(&8D6B,-1)            :\ &8FEA CHANGED from 8FF3
 1690RTS                             :\ Bodge 'Bad FS map' check
 1700]
 1710[OPT FNorg(&9483,&9A78)         :\ Check if hard drive present :\9A63 CHANGED from &9A6C
 1720LDA &FC47                       :\ &FF - absent, <>&FF - present
 1730CLC:ADC #1:BEQ DriveNotPresent  :\ &00 - absent, <>&00 - present INC A
 1740LDA #0:RTS                      :\ EQ - present
 1750.DriveNotPresent
 1760SEC:SBC #1:RTS                  :\ A=&FF - NE -> absent DEC A
 1770NOP:NOP:NOP:NOP:NOP:NOP
 1780\ next=&9498                    :\9A78 CHANGED FROM &9A7F
 1790]
 1800[OPT FNorg(&9AF6,-1)            :\ CHANGED from &9B0B
 1810\\JSR ReadBreak                 :\ Preserve context on Ctrl-Break  :\ CHANGED
 1820]
 1830[OPT FNorg(&9B7C,-1)            :\ Not Changed from &9B7C Can't find it !!
 1840\\JSR ReadBreak                 :\ Preserve context on Ctrl-Break  :\ CHANGED
 1850]
 1860[OPT FNorg(&960C,-1)            :\9C29 CHANGED from &9C2F
 1865\\JSR &A898
 1870LDA &B31B:CLC:ADC #1:BNE &9654  :\9C74 Lib not unset, jump ahead  :\ CHANGED INC A
 1880LDA &CD:AND #32:BEQ &9654:BNE &9621 :\9C74, 9C3B If HD, look for $.Library  :\ CHANGED
 1890RTS:RTS
 1895\ next=&9C3B
 1900]
 1910[OPT FNorg(&9DB8,-1)            :\ CHANGED from &9E07
 1920\\EQUS ver$                       :\ New version string
 1930]
 1940[OPT FNorg(&989B,-1)            :\9F6E CHANGED from &9F9B
 1950EQUB (MountCheck-1) DIV 256     :\ Ensure *MOUNT checks for LIB
 1960EQUB (MountCheck-1) AND 255
 1970]
 1971[OPT FNorg(&99A6,-1)            :\Changed from &A0C3
 1972RTS
 1973.BYE
 1974LDA (&B0),Y:CMP #&09             :\ Get command, CC=Read, CS=Write
 1975AND #&FD:EOR #&08:BEQ CommandOk  :\ Jump if Read (&08) or Write (&0A)
 1976LDA #&60:JMP CommandExit         :\ Return 'bad command' otherwise BRA CommandExit
 1977.CommandOk 
 1978LDY #9
 1979.CommandSaveLp
 1980LDA &7F,Y:PHA:LDA (&B0),Y:STA &7F,Y
 1981DEY:BNE CommandSaveLp           :\ Save &80-&89 and copy block
 1982JMP CommandSaveLp1              :\ Memory FULL
 1988]
 1989[OPT FNorg(&A07E,&AAF0) :\ Select sector for BGET/BPUT  :\AACA CHANGED from &AADD
 1990JSR WaitNotBusy:LDA #1:STA &FC42:CLC    :\ one sector
 2000LDA &B201,X:AND #63:ADC #1:STA &FC43    :\ Set sector b0-b5
 2010LDA &B202,X:ADC #0:STA &FC44            :\ Set sector b8-b15
 2020LDA &B203,X:STA &B333:JMP SetRandom     :\ Set sector b16-b21
 2030NOP:NOP
 2040\ next=&A0A4                            :\AAF0 CHANGED from &AB03
 2050]
 2060[OPT FNorg(&A10B,-1)            :\ BPUT to hard drive  :\AB57 CHANGED from &AB6A
 2070NOP:JMP &A117                   :\ Always jump to write  :\ CHANGED BRA &AB63                       
 2080:
 2090.ResultCodes
 2100EQUB &FF:EQUB &FF:EQUB &60:EQUB &FF
 2110EQUB &50:EQUB &65:EQUB &48:EQUB &FF
 2115\ next=&A117                       :\ Changed from &AB63
 2120]
 2130[OPT FNorg(&A125,-1)            :\AB72 CHANGED from &AB83
 2140NOP:NOP:NOP                     :\ Don't trample on IDE register
 2150]
 2160[OPT FNorg(&A12B,&AB87)         :\AB78 CHANGED from &AB89
 2170RTS                             :\ Remove IRQ routine
 2180:
 2190.UpdateDrive
 2200LDA &85:ORA &B317:STA &85       :\ Merge with current drive  :\ CHANGED
 2210STA &B333:LDA #&7F:RTS          :\ Store for any error  :\ CHANGED
 2220NOP
 2230\ next=&A13A                    :\AB87 CHANGED from &AB97
 2240]
 2250[OPT FNorg(&A25B,-1)            :\ BGET from hard drive  :\ACBA CHANGED from &ACC9
 2260NOP:NOP                         :\ Always continue into read
 2270]
 2280NEXT
 2290IF RIGHT$(file$,2)="31":file$=LEFT$(file$,LEN file$-2)+MID$(ver$,3):REM   :\ CHANGED
 2300PRINT"Save filename (";file$;:INPUT"): "A$:IF A$<>"":file$=A$
 2310OSCLI"Save "+file$+" "+STR$~mcode%+"+4000 FFFF0000 FFFF0000"