DISK variables: (needs proper translation) (MSX-DOS1)
BIOS System variables
Length
0004 2 Base Adress of the MSX Character Set
0006 1 Base Port Adress for the VDP data READ
0007 1 Base Port Adress for the VDP data WRITE
002B 1 Basic ROM Character set / Date format / Default interrupt freq
7 6 5 4 3 2 1 0
| | | | +-+-+-+-- Character set
| | | | 0 = Japanese, 1 = International, 2=Korean
| +-+-+---------- Date format
| 0 = Y-M-D, 1 = M-D-Y, 2 = D-M-Y
+---------------- Default interrupt frequency
0 = 60Hz, 1 = 50Hz
002C 1 Basic ROM Keyboard type / Basic version
7 6 5 4 3 2 1 0
| | | | +-+-+-+-- Keyboard type
| | | | 0 = Japanese, 1 = International
| | | | 2 = French (AZERTY), 3 = UK, 4 = German (DIN)
+-+-+-+---------- Basic version
0 = Japanese, 1 = International
002D 1 MSX Version Nuber
0 = MSX 1
1 = MSX 2
2 = MSX 2+
3 = MSX Turbo R
002E 1 IF BIT 0 = 1 then internal MIDI is present ( Turbo R Only !!! )
F197 00 DRIVE DPB drive A:+00 Drive bij the dpb (0=A, 1=B, etc)
F198 F9 ID +01 Media ID byte (0F8h/0F9h)
F199 00 SECSIZ (L) +02 Sector size (200h = 512 byte)
F19A 02 SECSIZ (H) +03 Idem
F19B 0F DIRMSK (SECSIZ/32)-1 +04 (Directory registraties in 1 sector)-1
F19C 04 DIRSHFT +05 Number of 1-bits in DIRMSK
F19D 01 CLUSMSK +06 (Number of sectors per cluster)-1
F19E 02 CLUSSHFT +07 (Number of 1-bits in CLUSMSK)+1
F19F 01 FIRFAT (L) +08 first sector of the FAT
F1A0 00 FIRFAT (H) +09 Idem
F1A1 02 FATCNT +0A number of FATs
F1A2 70 MAXENT +0B the max. number of directory registraties
F1A3 0E FIRREC (L) +0C first sector of the DATA gebied
F1A4 00 FIRREC (H) +0D Idem
F1A5 CA MAXCLUS (L) +0E the maximum number cluster
F1A6 02 MAXCLUS (H) +0F Idem
F1A7 03 FATSIZ +10 number sectors per FAT
F1A8 07 FIRDIR (L) +11 first sector of the DIRectory
F1A9 00 FIRDIR (H) +12 Idem
F1AA 97 FATADR (L) +13 address of the FAT storage in the RAM
F1AB E5 FATADR (H) +14 Idem
F1AC 00 DRIVE DPB drive B +00 Drive bij the dpb (0=A, 1=B, etc)
F1AD F9 ID +01 Media ID byte (0F8h/0F9h)
F1AE 00 SECSIZ (L) +02 Sector size (200h = 512 byte)
F1AF 02 SECSIZ (H) +03 Idem
F1B0 0F DIRMSK (SECSIZ/32)-1 +04 (Directory registraties in 1 sector)-1
F1B1 04 DIRSHFT +05 Number of 1-bits in DIRMSK
F1B2 01 CLUSMSK +06 (Number of sectors per cluster)-1
F1B3 02 CLUSSHFT +07 (Number of 1-bits in CLUSMSK)+1
F1B4 01 FIRFAT (L) +08 first sector of the FAT
F1B5 00 FIRFAT (H) +09 Idem
F1B6 02 FATCNT +0A number of FATs
F1B7 70 MAXENT +0B the max. number directory registraties
F1B8 0E FIRREC (L) +0C first sector of the DATA gebied
F1B9 00 FIRREC (H) +0D Idem
F1BA CA MAXCLUS (L) +0E the maximum number cluster
F1BB 02 MAXCLUS (H) +0F Idem
F1BC 03 FATSIZ +10 number sectors per FAT
F1BD 07 FIRDIR (L) +11 first sector of the DIRectory
F1BE 00 FIRDIR (H) +12 Idem
F1BF 97 FATADR (L) +13 address of the FAT storage in the RAM
F1C0 E5 FATADR (H) +14 Idem
F1C1 00 Diskdrive Stop Counterr (00 = Off)
Poke value 1 to this adress and call 0FD9Fh HOOK, it will become 0,
and the drive will stop spinning
F1C2 00 Diskdrive Stop , sub-counter
F1C3 00 Diskdrive Stop , sub-counter
F1C4 00 Active hardwarematic drive
F1C5 00 Last track-position of drive A before diskchange with drive B
F1C6 00 Last track-position of drive B before diskchange with drive A
F1C7 00 Active logic drive
F1C8 02 Number of hardwarematic drives available
F1C9 CD,6B,F3 CALL 0F36Bh Print textpointer in [DE] until '$' is found
F1CC 1A LD A,(DE) Similar to BDOS function number 9 (String Output)
F1CD CD,68,F3 CALL 0F368h
F1D0 13 INC DE
F1D1 FE,24 CP "$"
F1D3 C8 RET Z
F1D4 CD,A8,53 CALL 053A8h (in the diskrom)
F1D7 18,F0 JR 0F1C9h
F1D9 CD,6B,F3 CALL 0F36Bh Move data to RAM beneath ROM
F1DC ED,B0 LDIR
F1DE CD,68,F3 CALL 0F368H Rom on
F1E1 C9 RET
F1E2 CD,6B,F3 CALL 0F36Bh Execute in RAM
F1E5 C3,00,00 JP ABORTADRESS address to abort to
Jump to ABORTADRESS after Abort option is selected in DOS (Abort,Retry Ignore)
If the disk error handler is BEND (Changed) this will be called
after errorhandler returns (C=2 Abort)
F1E8 Jump to address in pointer (HL)
HL = address pointer
Remark!: First switches RAM in Page 1 (F36B) then switches DISKROM Page 1(F368)
F1E8 11,DE,F1 LD DE,0F1DEh JP (HL) to routine in RAM
F1EB D5 PUSH the Returns adress on the STACK of the ROM
F1EC 5E LD E,(HL) Put back On
F1ED 23 INC HL
F1EE 56 LD D,(HL) Get adress
F1EF EB EX DE,HL
F1F0 CD,6B,F3 CALL 0F36Bh switches RAM in Page 1
F1F3 E9 JP (HL)
F1F4 C3,04,56 JP 5604 Check filename (HL=pointer). Results stored in pointer [DE,->)
F1F7 50,52,4E,20 "PRN " Device names
F1FB 4C,53,54,20 "LST "
F1FF 4E,55,4C,20 "NUL "
F203 41,55,58,20 "AUX "
F207 43,4F,4E,20 "CON "
F20B 20,20,20,20 storage for found filename ( AUX,CON etc )
F20F 20,20,20,20
F213 20,20,20 Extension
F216 80 Ge-NEG-t device number. PRN=-5, LST=-4 ... CON=-1
F217 00
F218 00
F219 00
F21A 00
F21B 00
F21C 00
F21D 00
F21E 00
F21F 00
F220 00
F221 00,00 DATE of the Found file from the FCB
F223 00,00 TIME of the Found file from the FCB
F225 00
F226 00
F227 00
F228 00
F229 00
F22A 00
F22B 1F January Number of days in January this month in this year
F22C 1C February Number of days in February this month in this year
F22D 1F March Number of days in March this month in this year
F22E 1E April Number of days in April this month in this year
F22F 1F May Number of days in May this month in this year
F230 1E June Number of days in June this month in this year
F231 1F July Number of days in July this month in this year
F232 1F August Number of days in August this month in this year
F233 1E September Number of days in September this month in this year
F234 1F October Number of days in October this month in this year
F235 1E November Number of days in November this month in this year
F236 1F December Number of days in December this month in this year
F237 00,00,00,00 Variables of BUFINP (BDOS function 10)
F23B 00 Printer on (Dos : ^P) NZ = On
F23C 00
F23D 79 Current DMA adres
F23E DD
F23F FE Sector number
F240 01
F241 00
F242 01
F243 97 DPB address of the current drive
F244 F1
F245 00 Current sector inside directory (0-based), Used by SEARCH FIRST and NEXT routines
F246 00 Drive of the current directory
F247 00 Default drive 0=A, 1=B etc.
F248 10 Day
F249 0B Month
F24A 09 Year (L)
F24B 00 Year (H) -1980
F24C 17 Time
F24D 0E Time
F24E 04 Day of the week
F24F C9 (625A) From "Insert disk for drive" routine
F250 C9 [AF] Contains the drive in CHAR format (41h = "A")
F251 C9
F252 C9 (41FA)
F253 C9
F254 C9
F255 C9 (425A) From the fix-filename routine.
F256 C9
F257 C9
F258 C9 (42BC) Is used by several routines
F259 C9 With this adress (F2DC) can be changed to see sub-directory's
F25A C9 when "FILES" command is used in BASIC (allways)
F25B C9 (4317) Is called by DIRENT increase routine,
F25C C9 after this the new DIRENT value is stored in [AF]
F25D C9
F25E C9 (4348) Is called by routine that loads the next sector of the current directory
F25F C9
F260 C9
F261 C9 (440E) From Fix filename routine
F262 C9
F263 C9
F264 C9 (4471) From the OPEN routine
F265 C9
F266 C9
F267 C9 ( )
F268 C9
F269 C9
F26A C9 (4553) From the GETDPB routine
F26B C9
F26C C9
F26D C9 (45CF) From the CLOSE routine
F26E C9
F26F C9
F270 C9 (46C5) DISKREAD [HL]=DMA
F271 C9 Read sector [DE]=Sector
F272 C9 BDOS:2Fh [B] =Number of sectors
F273 C9 (470A)
F274 C9
F275 C9
F276 C9 (4748)
F277 C9
F278 C9
F279 C9 (4755) DISKWRT [HL]=DMA
F27A C9 Write sector [DE]=Sector
F27B C9 BDOS:30h [B] =Number of sectors
F27C C9 (4916) From the HL=DE*BC routine
F27D C9
F27E C9
F27F C9 (492F) From the BC=BC/DE; HL=rest routine
F280 C9
F281 C9
F282 C9 (4989)
F283 C9
F284 C9
F285 C9 (49B1)
F286 C9
F287 C9
F288 C9 (4A36)
F289 C9
F28A C9
F28B C9 (4A46)
F28C C9
F28D C9
F28E C9 (4B56)
F28F C9
F290 C9
F291 C9 (4BE2)
F292 C9
F293 C9
F294 C9 (4C22)
F295 C9
F296 C9
F297 C9 (4C97)
F298 C9
F299 C9
F29A C9 (4D05)
F29B C9
F29C C9
F29D C9 (4D8C)
F29E C9
F29F C9
F2A0 C9 (4E48)
F2A1 C9
F2A2 C9
F2A3 C9 (4EDB)
F2A4 C9
F2A5 C9
F2A6 C9 (4F12)
F2A7 C9
F2A8 C9
F2A9 C9 (4F9E)
F2AA C9
F2AB C9
F2AC C9 (5104) BUFINP (BDOS 10), just before the DIRIN2 call (BDOS 02) is called
F2AD C9
F2AE C9
F2AF C9 (53A8) Is called at the beginning of the CONOUT routine
F2B0 C9
F2B1 C9
F2B2 C9 (5496)
F2B3 C9
F2B4 C9
F2B5 C9 (5523) Leap Year calculation (february = 28/29 days)
F2B6 C9
F2B7 C9
F2B8 00 DIRENT Current entry in the directory
F2B9 44 Filename storage
F2BA 49
F2BB 53
F2BC 4B
F2BD 52
F2BE 4F
F2BF 4D
F2C0 20
F2C1 56
F2C2 41
F2C3 52
F2C4 00 If BIT 7 of this attribute is SET then files with a NOT 0 attribute can be opend
This can be done by setting bit 7 of the FCB-drive byte, when calling BDOS OPEN routine (=FCB+0)
F2C5 00
F2C6 00
F2C7 00
F2C8 00
F2C9 00
F2CA 00
F2CB 00
F2CC 00
F2CD 00
F2CE 00
F2CF 00 (2) Time
F2D0 00
F2D1 00 (2) Date
F2D2 00
F2D3 00 (2) first cluster ( The first file is allways 2)
F2D4 00
F2D5 00 (4) File size
F2D6 00
F2D7 00
F2D8 00
F2D9 00
F2DA 00
F2DB 00
F2DC 00 If Not Zero, Files with a NOT 0 attribute will be accepted (F2C4 bit 7 overrules this !)
F2DD 01
F2DE 00
F2DF 01
F2E0 80
F2E1 00 Current drive of absolute disk read/write
F2E2 79
F2E3 DE
F2E4 00
F2E5 0A
F2E6 00
F2E7 00
F2E8 00
F2E9 01
F2EA 02
F2EB 00
F2EC FC
F2ED 00
F2EE 06
F2EF 00
F2F0 06
F2F1 00
F2F2 00
F2F3 00
F2F4 00
F2F5 0C
F2F6 00
F2F7 00
F2F8 00
F2F9 00
F2FA 00
F2FB 00
F2FC 00
F2FD 00
F2FE 2A Same as (F2B8) (subcounter)
F2FF 01
F300 00
F301 00
F302 CA
F303 02
F304 00 Store Stack Pointer (SP)
F305 00
F306 00 Default drive of MSXDOS
F307 00 storage of the (=FCB pointer), Same as [C] > 11, in the BDOS call (0F37Dh)
F308 00
F309 00 storage of the DPB address by Search first and next
F30A 00
F30B FF Current Directory entry when Searching.
F30C 00
F30D 00 Verify flag (NZ=on)
F30E 01 Date format (0 = YYMMDD, 1 = MMDDYY, 2 = DDMMYY)
F30F 00 (4) Is used by KANJI
F310 00
F311 00
F312 00
F313 00 Contains Disk Basic Version - 0 = Disk Basic 1.x / <> 0 = Disk basic 2.x (Dos 2.x)
F314 00
F315 00
F316 00
F317 00
F318 00
F319 00
F31A 00
F31B 00
F31C 00
F31D 00
F31E 00
F31F 00
F320 00
F321 00
F322 00
F323 AE ERRADR Stores a adress to jump to, if an error occurs
F324 72
F325 6C CTRLCAD Stores a adress to jump to, if ^C (CTRL + C) is pressed
F326 5C
F327 3E Cursor position Is used in combination with (F329) by AUXINP (F371)
F328 1A Same Only then LD A,^Z
F329 C9 RET
F32A C9
F32B C9
F32C C9 JP of AUXOUT
F32D C9
F32E C9
F32F C9
F330 C9
F331 F7 RST 30h Perform BDOS
F332 8F Slot ID (i.e. 3-3)
F333 D3 address (i.e. 56D3)
F334 56
F335 C9 RET
F336 00 Keyboard readout. If F336 = <> 0 (F337) contains a value
F337 00 if both are 03 then CTRL-STOP is pressed
In some routines F336 <> 0 -> ^S is possible
F338 FF Clockchip indicator ( IF <> 0 then Clockchip is present / IF = 0 then No clockchip)
F339 00 (2) stores SP when calling (input-current-date routine) from (diskrom)
F33A 00
F33B B5 (2) stores HL when calling clockchip routine
F33C 05
F33D 01
F33E 00
F33F 00
F340 F3 REBOOT ( IF = 0 DOS will initialized all settings again )
F341 8B Slot ID of RAM in page 0 (DOS) (i.e. 3-2)
F342 8B Slot ID of RAM in page 1 (DOS)
F343 8B Slot ID of RAM in page 2 (DOS/BASIC)
F344 8B Slot ID of RAM in page 3 (DOS/BASIC)
F345 07 Is used when calculating free buffers (025h)
F346 00 Test if system is booted with DOS (CALL SYSTEM possible ? <> 0 = Yes / 0 = No)
F347 02 Totaal number logical drives connected ( i.e. CALL FORMAT reads this value )
F348 8F Slot ID of the DISKROM (i.e. 3-3)
F349 95 HIGHMEM RAM between HIGHMEM and (F37F) will be used by DISKROM
F34A DF
F34B 00 CLEAR Start adress of free RAM in DOS. COMMAMD.COM is loaded from this adress (0100h)
F34C 00
F34D 97 Temporary storage for (FAT sector) pointer
F34E EF
F34F 97 Temporary storage for (DATA sector) pointer
F350 ED
F351 97 Temporary storage for (DIRECTORY sector) pointer (Also used by DSKI$ & DSKO as pointer to sector)
F352 EB
F353 92
F354 DE
' Address of the Drive Parameter Block
F355 97,F1 drive A:
F357 AC,F1 drive B:
F359 00,00 drive C:
F35B 00,00 drive D:
F35D 00,00 drive E:
F35F 00,00 drive F:
F361 00,00 drive G:
F363 00,00 drive H:
F365 DB IN A,(0A8H)
F366 A8
F367 C9 RET
F368 C9 ROMUSE Switch DISKROM to page 1 (DOS only)
F369 00
F36A 00
F36B C9 RAMUSE Switch RAM to page 1 (DOS only)
F36C 00
F36D 00
' Inter slot Move
F36E C9 Move ROM to RAM HL = source, DE = destination, BC = length (DOS only)
F36F 00
F370 00
F371 C3 AUXINP Aux device input. Is bend to a routine and returns result in [AF]
F372 27
F373 F3
F374 C3 AUXOUT Aux device output. Is bend to a routine and returns RET as result
F375 2C
F376 F3
F377 C3 Bload
F378 79
F379 DE
F37A C3 Bsave
F37B 87
F37C DE
F37D C3 ROMBDOS - ROM BDOS vector
F37E 31
F37F F3
.WORK AREA LISTING
;
.SUBROUTINES FOR READ/WRITE CALLS OF THE INTER-SLOT
;
F380 RDPRIM Read from basic slot, used by RDSLT (0Ch) BIOS routine
F385 WRPRIM Write to basic slot, used by WRSLT (14h) BIOS routine
F38C CLPRIM Call basic slot, used by CALSLT (1Ch) BIOS routine
F39A USRTAB USR function starting USR(0)
F39C USRTAB USR function starting USR(1)
F39E USRTAB USR function starting USR(2)
F3A0 USRTAB USR function starting USR(3)
F3A2 USRTAB USR function starting USR(4)
F3A4 USRTAB USR function starting USR(5)
F3A6 USRTAB USR function starting USR(6)
F3A8 USRTAB USR function starting USR(7)
F3AA USRTAB USR function starting USR(8)
F3AC USRTAB USR function starting USR(9)
F3AE LINL40 Screen width per line in SCREEN 0 (Default 39)
F3AF LINL32 Screen width per line in SCREEN 1 (Default 29)
F3B0 LINLEN Current screen width per line
F3B1 CRTCNT Number of lines of current screen (default 24)
F3B2 CLMLST Horizontal location in the case that items are divided by commas in PRINT statement
.WORK FOR INITIALIZATION
-SCREEN 0
F3B3 TXTNAM Pattern name tabte
F3B5 TXTCOL Color table
F3B7 TXTCGP Pattern ganarator table
F3B9 TXTATR Unused
F3BB TXTPAT Unused
-SCREEN 1
F3BD T32NAM Pattern name tabte
F3BF T32COL Color table
F3C1 T32CGP Pattern ganarator table
F3C3 T32ATR Sprite attribute table
F3C5 T32PAT Sprite generator table
-SCREEN 2
F3C7 GRPNAM Pattern name tabte
F3C9 GRPCOL Color table
F3CB GRPCGP Pattern ganarator table
F3CD GRPATR Sprite attribute table
F3CF GRPPAT Sprite generator table
-SCREEN 3
F3D1 MLTNAM Pattern name tabte
F3D3 MLTCOL Color table
F3D5 MLTCGP Pattern ganarator table
F3D7 MLTATR Sprite attribute table
F3D9 MLTPAT Sprite generator table
F3DB CLIKSW Key click switch 0 = Disabled / 1 = Enabled
F3DC CSRY Y-coordinate of text cursor
F3DD CSRX X-coordinate of text cursor
F3DE CNSDFG Functon key display switch 0 = NOT Visible / 1 = Visible
.AREA TO SAVE VDP REGISTERS
F3DF RG0SAV Content of VDP(0) register (R#0)
F3E0 RG1SAV Content of VDP(1) register (R#1)
F3E1 RG2SAV Content of VDP(2) register (R#2)
F3E2 RG3SAV Content of VDP(3) register (R#3)
F3E3 RG4SAV Content of VDP(4) register (R#4)
F3E4 RG5SAV Content of VDP(5) register (R#5)
F3E5 RG6SAV Content of VDP(6) register (R#6)
F3E6 RG7SAV Content of VDP(7) register (R#7)
F3E7 STATFL Content of VDP(8) register (MSX2- VDP status register 0 S#0)
F3E8 TRGFLG Stores trigger button status of joystick
Information about trigger buttons and space bar state
7 6 5 4 3 2 1 0
| | | | +-- Space bar, trig(0) (0 = pressed)
| | | +---------- Stick 1, Trigger 1 (0 = pressed)
| | +------------ Stick 1, Trigger 2 (0 = pressed)
| +-------------- Stick 2, Trigger 1 (0 = pressed)
+---------------- Stick 2, Trigger 2 (0 = pressed)
F3E9 FORCLR Foreground colour
F3EA BAKCLR Background colour
F3EB BDRCLR Border colour
F3EC MAXUPD JMP 0000 (used by CIRCLE statement)
F3EF MINUPD JMP 0000 (used by CIRCLE statement)
F3F2 ATRBYT Color code in csing graphic
.WORK AREA FOR PLAY STATEMENT
F3F3 QUEUES Points to queue table at the execution of PLAY st.
F3F5 FRCNEW DB 255
.WORK AREA FOR KEY INPUT
F3F6 SCNCNT Interval for the key scan
F3F7 REPCNT Delay until the auto-repeat of the key begins
F3F8 PUTPNT DW KEYBUF points to adress to write in the key buffer
F3FA GETPNT DW KEYBUF points to adress to read from the key buffer
.PARAMETERS FOR CASSETTE
F3FC CS120 DB LOW01,HIGH01,LOW11,HIGH11,HEDLEN*2/256 ; FOR 1200 BAUD
F401 CS120 DB LOW02,HIGH02,LOW12,HIGH22,HEDLEN*2/256 ; FOR 2400 BAUD
F406 LOW DB LOW01,HIGH01 Width of LOW & HIGH wich represents bit 0
F408 HIGH DB LOW11,HIGH11 Width of LOW & HIGH wich represents bit 1
F40A HEADER DB HEDLEN*2/256 Header bit for the short header
F40B ASPCT1 256/aspect ratio for BASIC Circle command
F40D ASPCT2 256*aspect ratio for BASIC Circle command
F40F ENDPGM DB ":" Dummy program end for RESUME NEXT st.
.WORK USED BY BASIC INTERNALLY
F414 ERRFLG BASIC Error number
F415 LPTPOS Position of printer head
F416 PRTFLG Flag whether to send to printer 0 = Print to Screen / 1 = Print to printer
F417 NTMSXP = 0 If MSX printer (This converts TAB's and unknown characters to spaces)
F418 RAWPRT <>0 If printing is in 'RAW MODE'
F419 VLZADR ADDRESS OF CHARACTER REPLACED BY VAL
F41B VLZDAT CHARACTER REPLACED WITH 0 BY VAL
F41C CURLIN Current execution line number of BASIC
F41E KBFMIN Same as ENDPRG, used if direct statement error occures
F41F KBUF Crunch buffer;translated into intermediate language from BUF
F55D BUFMIN used by INPUT routine
F55E BUF Buffer to store characters typed( in ASCII code)
F562 SX VDP R# 32, Source X Low
F563 SX VDP R# 33, Source X High
F564 SY VDP R# 34, Source Y Low
F565 SY VDP R# 35, Source Y High
F566 DX VDP R# 36, Dest. X Low
F567 DX VDP R# 37, Dest. X High
F568 DY VDP R# 38, Dest. Y Low
F569 DY VDP R# 39, Dest. Y High
F56A NX VDP R# 40, Nr of dots X Low
F56B NX VDP R# 41, Nr of dots X High
F56C NY VDP R# 42, Nr of dots Y Low
F56D NY VDP R# 43, Nr of dots Y High
F56E CDUMMY VDP R# 44, Color register
F56F ARG VDP R# 45, Argument register
F570 L_OP VDP R# 46, Command register
The above Bit-blitten addresses are used by the COPY command in Basic.
The VDP is allso able to communicate with the DISKROM to
save or load images from or to VRAM.
A 2Byte filename pointer is expected in SX for Loading and DX for Writing operation.
i.e. FNAAM: DEFB 34,"d:filename.ext",34,0
See SUB-ROM / EXT-ROM (BIT-BLIT routines)L_OP has 10 different operators: 0 - PSET 1 - AND 2 - OR 3 - XOR 4 - PRESET 8 - TPSET 9 - TAND 10 - TOR 11 - TXOR 12 - TPRESET
F660 ENDBUF Preventoverflow of BUF F661 TTYPOS Virtual cursor location internally retained by BASIC F662 DIMFLG ARRAY FLAG F663 VALTYP Contains the code of the type of variable that is currently in DAC
2 = Integer 3 = String 4 = Single Precision 5 = Double PrecisionF664 DORES Indicates whether stored word can be crunched F665 DONUM flag for crunch F666 CONTXT Text address used by CNRGET F668 CONSAV Store token of constant after calling CHRGET F669 CONTYP Type of stored constant F66A CONLO Valu of stored constant F672 MEMSIZ HIGHEST LOCATION IN MEMORY USED BY BASIC F674 STKTOP TOP LOCATION TO BE USED FOR THE STACK F676 TXTTAB Starting address of BASIC text area F678 TEMPPT Starting address of unused area of temporary descriptor F67A TEMPST Temporary descriptors F698 DSCTMP String descriptor wich is the result of string fun. F69B FRETOP Starting address of unused area of string area F69D TEMP3 Used for garbage collection or by USR function F69F TEMP8 Used for garbage collection F6A1 ENDFOR Next address of FOR st. F6A3 DATLIN Line number of DATA st.read by READ st. F6A5 SUBFLG Flag for array for USR fun. F6A6 FLGINP Flag for INPUT or READ F6A7 TEMP Location for temporary reservation for st.code F6A9 PTRFLG LINE NUMBER CONVERTED TO POINTERS ( 00 = NO / 0D = Yes ) F6AA AUTFLG AUTO MODE FLAG ( 00 = Yes / 01 = No ) F6AB AUTLIN Current line number for auto F6AD AUTINC Increment for auto F6AF SAVTXT Text pointer for resume F6B1 SAVSTK Save stack when error occurs F6B3 ERRLIN Line where last error F6B5 DOT CURRENT LINE for edit & list F6B7 ERRTXT Text pointer for use by RESUME F6B9 ONELIN LINE to go when error F6BB ONEFLG =1 if executing an error trap routine F6BC TEMP2 F6BE OLDLIN OLD LINE NUMBER set up ^C ... F6C0 OLDTXT Points st. to be executed next F6C2 VARTAB Pointer to start of variable space F6C4 ARYTAB Pointer to begging of array table F6C6 STREND End of storage in use F6C8 DATPTR DATA pointer F6CA DEFTBL Default valtype for each letter
.WARK FOR USER FUNCTION PARAMETERF6E4 PRMSTK Previous definition block on stack F6E6 PRMLEN Number of bytes of objective table F6E8 PARM1 Objective prameter definition table F74C PRMPRV Pointer to previous parameter block F74E PRMLN2 Size of parameter block F750 PARM2 For parameter storage F7B4 PRMFLG Flag to indicate whether PARM1 was searching F7B5 ARYTA2 End point of search F7B7 NOFUNS 0 if no function active F7B8 TEMP9 Location of temporary storage for garbage collection F7BA FUNACT Count of active functions F7BC SWPTMP Value of first variable in SWAP st. F7C4 TRCFLG 0 MEANS NO TRACE
.WORK FOR MATH-PACKF7C5 FBUFFR Buffer for fout F7F0 DECTMP Used to transform decimal integer to floating point number F7F2 DECTM2 Used at division routine execution F7F4 DECCNT Used at division routine execution F7F6 DAC DECIMAL ACCUMULATOR (Interger in USR()-function stored to #F7F8) F806 HOLD8 Registers for decimal multiplication F836 HOLD2 Work area in the execution of numerical operators F83E HOLD Work area in the execution of numerical operators F847 ARG Area to set the value to be calculate with DAC F857 RNDX Last random number
.DATA AREA USED BY BASIC INTERPRETERF85F MAXFIL High legal file number F860 FILTAB Starting address of of file data area F862 NULBUF Points to file 0 buffer ( used in SAVE & LOAD st.) F864 PTRFIL Points to file data of currently accessing file F866 RUNFLG Non-zero for run after load F866 FILNAM Name for FILES, NAME & others F871 FILNM2 Second name for NAME F87C NLONLY When loading program ( 00 = NON BASIC / 01 = BASIC ) F87D SAVEND End address for BSAVE F87F FNKSTR FUNCTION KEY AREA F91F CGPNT Slot ID of the character FONT F920 Address of the character FONT F922 NAMBAS Base address of current pattern name table F924 CGPBAS Base address of current pattern generator table F926 PATBAS Base address of current sprite generator table F928 ATRBAS Base address of current sprite attribute table
F92A CLOC Cursor Location F92C CMASK Mask of Cursor F92D MINDEL Used by LINE command in BASIC F92F MAXDEL Used by LINE command in BASIC
.DATA AREA FOR CIRCLE STATEMENTF931 ASPECT Aspect ratio of the circle; set by <ratio> of CIRCLE F933 CENCNT End count F935 CLINEF Flag to draw line to centre F936 CNPNTS Point to be plottted F938 CPLOTF Plot polarity flag F939 CPCNT 1/8 of number of points in circle F93B CPCNT8 F93D CRCSUM F93F CSTCNT F941 CSCLXY Scale of X & Y F942 CSAVEA reservation area of ADVGRP F944 CSAVEM reservation area of ADVGRP F945 CXOFF X offset from center F947 CYOFF Y offset from center
.DATA AREA FOR PAINT STATEMENTF949 LOHMSK Used by PAINTcommand in BASIC F94A LOHDIR Used by PAINTcommand in BASIC F94B LOHADR Used by PAINTcommand in BASIC F94D LOHCNT Used by PAINTcommand in BASIC F94F SKPCNT Skip count, Used by PAINTcommand in BASIC F951 MOVCNT Movement count, Used by PAINTcommand in BASIC F953 PDIREC Direction of the paint, Used by PAINTcommand in BASIC F954 LFPROG Used by PAINTcommand in BASIC F955 RTPROG Used by PAINTcommand in BASIC F956 MCLTAB Used by DRAW / PLAY command in BASIC F958 MCLFLG Used by DRAW / PLAY command in BASIC F959 QUETAB queue information (VOICAQ, VOICBQ, VOICCQ and RS2IQ (RS232)) F971 QUEBAK F975 VOICAQ 1st Voice of Play Buffer (PSG) If MSX-Music is present area #F9C0-#F9F8 is used to store copy of YM2413 registers F9F5 VOICBQ 2st Voice of Play Buffer (PSG) FA75 VOICCQ 3st Voice of Play Buffer (PSG) FAF5 DPPAGE Display page number (SET PAGE X) FAF6 ACPAGE active page number (SET PAGE ,X) FAF7 AVCSAV Reserves AV control port FAF8 EXBRSA SUB_ROM / EXT-ROM slot address FAF9 CHRCNT Character counter in the buffer, used in KANA-ROM FAFA ROMA Area to store KANA character (Japan version only) FAFC MODE mode switch for VRAM size FAFD NORUSE unused <edit> Used by KANJI-ROM for rendering KANJI fonts in graphic modes:
bit 7 Don't return to textmode bit 6 if 1 and #f7f4 (DECCNT)=0, read SHIFT status ??? bit 5 Disable some functinality bit 4 Not in use bit 3 color 0 = Transparent BIT 0-2: Logical operation on kanji font draw: 0 PSET 1 AND 2 OR 3 XOR 4 NOT
FAFE XSAVE [10000000 XXXXXXXX] X-coordinate Mouse/Trackball/Lightpen FB00 YSAVE [*0000000 YYYYYYYY] Y-coordinate Mouse/Trackball/Lightpen FB02 LOGOPR Logical operation code
Data area used by RS-232C or disk driveFB03 RSTMP Temporary data storage for RS232 Driver FB03 TOCNT FB04 RSFCB Adress of the RS232 LOW FB05 RSFCB Adress of the RS232 HIGH FB06 RSIQLN Byte DATA FB07 MEXBIH Hook RST (&H30) FB08 Byte Data FB09 LOW FB0A HIGH FB0B OLDINT Old interupt ( RET &HC9 ) FB0C OLDSTT Hook FB10 Unknown FB11 Hook RST (&H30) FB12 OLDINT Byte DATA FB13 LOW FB14 HIGH FB15 ( RET &HC9 ) FB16 DEVNUM Byte OFFSET FB17 DATCNT Byte DATA FB18 Byte POINTER FB19 Byte POINTER FB1A ERRORS Byte DATA FB1B FLAGS BIT BOOLEAN FB1C ESTBLS BIT BOOLEAN FB1D COMMSK Byte DATA FB1E LSTCOM Byte DATA FB1F LSTMOD Byte DATA FB20
.Data area used by MSX-DOSBF21 DRVINV Nr. of drives connected to disk interface 1 BF22 DRVINV Slot adress of disk interface 1 BF23 DRVINV Nr. of drives connected to disk interface 2 BF24 DRVINV Slot adress of disk interface 2 BF25 DRVINV Nr. of drives connected to disk interface 3 BF26 DRVINV Slot adress of disk interface 3 BF27 DRVINV Nr. of drives connected to disk interface 4 BF28 DRVINV Slot adress of disk interface 4
musicFB35 PRSCNT Used by PLAY command in BASIC FB36 SAVSP Used by PLAY command in BASIC FB38 VOICEN Used by PLAY command in BASIC FB39 SAVVOL Used by PLAY command in BASIC FB3B MCLLEN Used by PLAY command in BASIC FB3C MCLPTR Used by PLAY command in BASIC FB3E QUEUEN FB3F MUSICF FB40 PLYCNT FB41 VCBA FB66 VCBB FB8B VCBC FBB0 ENSTOP <>0 if warm start enabled (CTRL+SHIFT+GRPH+KANA/CODE for warm start) FBB1 BASROM <>0 if basic is in rom (CTRL+STOP disabled) FBB2 LINTTB line terminator table (<>0 if line terminates) FBCA FSTPOS first position for inlin FBCC CODSAV code save area for cursor FBCD FNKSWI indicate which func key is displayed FBCE FNKFLG fkey which have subroutine FBD8 ONGSBF global event flag FBD9 CLIKFL FBDA OLDKEY FBE5 NEWKEY
- Example of European Keyboard Layout FBE5 0 => 7 6 5 4 3 2 1 0 FBE6 1 => ; ] [ \ = - 9 8 FBE7 2 => B A ACCENT / . , ` ' FBE8 3 => J I H G F E D C FBE9 4 => R Q P O N M L K FBEA 5 => Z Y X W V U T S FBEB 6 => F3 F2 F1 CODE CAPS GRPH CTRL SHIFT FBEC 7 => RET SEL BS STOP TAB ESC F5 F4 FBED 8 => RIGHT DOWN UP LEFT DEL INS HOME SPACE FBEE 9 => 4 3 2 1 0 / + * FBEF 10 => . , - 9 8 7 6 5
FBF0 KEYBUF key code buffer FC18 BUFEND end of key buffer FC18 LINWRK FC40 PATWRK Pattern Buffer FC48 BOTTOM FC4A HIMEM FC4C TRPTBL FC9A RTYCNT FC9B INTFLG This flag is set if STOP or CTRL + STOP is pressed
0 = Not Pressed 3 = CTRL +STOP Pressed 4 = STOP PressedFC9C PADY Y-coordinate of a connected Graphics Tablet (PAD) FC9D PADX X-coordinate of a connected Graphics Tablet (PAD) FC9E JIFFY Contains value of the software clock, each interrupt of the VDP it is increased by 1.
The contents can be read or changed by the 'TIME' function or 'TIME' statement.FCA0 INTVAL Contains length of the interval when the ON INTERVAL routine was established. FCA2 INTCNT ON INTERVAL counter (counts backwards) FCA4 LOWLIM Used by the Cassette system (minimal length of startbit) FCA5 WINWID Used by the Cassette system (store the difference between a low-and high-cycle) FCA6 GRPHED flag for graph. char FCA7 ESCCNT escape sequence counter FCA8 INSFLG insert mode flag FCA9 CSRSW cursor display switch FCAA CSTYLE cursor style i.e. Used if INS Key is used ( 00# = Full Cursor / FF# = Halve Cursor ) FCAB CAPST capital status ( 00# = Off / FF# = On ) FCAC KANAST russian key status (Dead Keys)
0 = No Dead Keys 1 = Dead Key > Accent Grave 2 = SHIFT + Dead Key > Accent Egu 3 = CODE + Dead Key > Accent Circumflex 4 = SHIFT + CODE + Dead Key > TremaFCAD KANAMD FCAE FLBMEM 0 if loading basic programm FCAF SCRMOD screen mode FCB0 OLDSCR old screen mode FCB1 CASPRV FCB2 BRDATR border color for paint FCB3 GXPOS X-position FCB5 GYPOS Y-position FCB7 GRPACX FCB9 GRPACY FCBB DRWFLG Used by the DRAW statement (DrawFlag)
Bit 7 = Draw Line 0 = No / 1 = Yes ( ,N ) Bit 6 = Move Cursor 0 = Yes / 1 = Yes ( ,B ) Bit 5 - 0 UnusedFCBC DRWSCL Used by the DRAW statement (DrawScaling) FCBD DRWANG Used by the DRAW statement (DrawAngle)
0 = 0° rotation 1 = 90° rotation 2= 180° rotation 3= 270° RotationFCBE RUNBNF Run Binary File After loading ( Bload"File.Bin",R ) 0 = Don't Run / 1 = Run FCBF SAVENT start address for BSAVE / BLOAD operations FCC1 EXPTBL flag for primary expanded slot 0 80h = Expanded / 00h = NOT Expanded FCC2 EXPTBL flag for primary expanded slot 1 80h = Expanded / 00h = NOT Expanded FCC3 EXPTBL flag for primary expanded slot 2 80h = Expanded / 00h = NOT Expanded FCC4 EXPTBL flag for primary expanded slot 3 80h = Expanded / 00h = NOT Expanded FCC5 SLTTBL current expanded slot 0 reg FCC6 SLTTBL current expanded slot 1 reg FCC7 SLTTBL current expanded slot 2 reg FCC8 SLTTBL current expanded slot 3 reg FCC9 SLTATR Slotatributes found during start process
Bit 7 = Basic programm 0 = No / 1 = Yes Bit 6 = Device Extention 0 = No / 1 = Yes Bit 5 = Statement Extention 0 = No / 1 = Yes Bit 4 - 0 = UnusedFD09 SLTWRK (free word = FD09H + 32*basic slot + 8*expansion slot + 2*page) FD89 PROCNM name of expanded statement FD99 DEVICE device ID for cartrige 0-3
HOOKS:
THE USE OF HOOKS
Hooks provide a way to intercept the BASIC interpreter or operating system at
certain points,enabling additional,or alternative,processing to be carried out.To
expand on the last sentence it i s easiest to use an to be carried out.To expand
on the last sentence it iseasiest to use an example.Consider for example the BIOS
call CHPUT(see section 2.3).This routine is used to print text on the screen.Here
is a disassembly of the first few instructions of CHPUT :
PUSH HL SAVE ALL THE REGISTERS USED
PUSH DE
PUSH BC
PUSH AF
CALL FDA4 CALL THE HOOK HCHPU
First of all registers HL,BC,DE and AF are pushed on to the stack.Then memory
address FDA4 is called.Normally,the contents of FDA4 and the following 4
bytes,is a Z80 RET instruction,immediately passing control to the instruction
following the CALL.However,FDA4 is in RAM,so its contents can be altered.Let
the 3 bytes,starting at FDA4 be changed,so that control is passed to another
subroutine at D000,i.e.
FDA4 C3 00 D0 JP D000
Also let the code at D000 be as shown below :
POP HL GET RID OF THE FIRST ITEM ON THE
STACK(i.e.RETURN TO HOOK ADDRESS)
POP AF RESTORE THE REGISTERS
POP BC
POP DE
POP HL
RET EXIT BIOS CALL CHPUT.
Now the item on the top of the stack is 3 more than the address from which
FDA4 was called,i.e.the return address to CHPUT.Therefore,if this is removed
from the stack,this will restore the stack to the state it was in immediately
before calling FDA4.Also,if the next four items are popped as shown above,the
stack will be as it was on entering CHPUT,so the RET instruction will exit the
subroutine CHPUT.Consequently the character which was to be printed will not be !
This example demonstrates how the operating system can be intercepted.The five
bytes,starting at address FDA4,are know as a hook.Similar "hook" exist at many
other points in the operating system and BASIC interpreter,and a list of them,in
alphabetical order,is contained in the following pages.
-----------------------------------------------------------------
+ No RET on hook
+/c No RET on hook if network is present
+/sc Hook doesn't change for sc 8
-----------------------------------------------------------------
+/c FD9A+ HKEYI 0C4A Interrupt handler
FD9F+ HTIMI 0C53 Interrupt handler
FDA4+/scHCHPU 08C0 ÄÏ CHPUT(A-character;SAVE ALL)
FDA9+/scHDSPC 09E6 Display cursor (no param.)
FDAE+/scHERAC 0A33 Errase cursor (no param.)
FDB3+/scHDSPF 0B2B DSPFNK std routine(no param.)
FDB8+/scHERAF 0B15 ERAFNK std routine(no param.)
FDBD HTOTE 0842 TOTEXT std routine
FDC2+ HCHGE 10CE CHGET std routine
FDC7+ HINIP 071E Copy character set to VDP
FDCC HKEYC 1025 Keyboard decoder
FDD1 HKYEA 0F10 Keyboard decoder
FDD6 HNMI 1398 NMI std routine
FDDB HPINL 23BF PINLIN std routine
FDE0 HQINL 23CC QINLIN std routine
FDE5 HINLI 23D5 INLIN std routine
FDEA HONGO 7810 "ON DEVICE GOSUB"
FDEF+ HDSKO 7C16 "DSKO$"
FDF4 HSETS 7C1B "SET"
FDF9+ HNAME 7C20 "NAME"
FDFE+ HKILL 7C25 "KILL"
FE03 HIPL 7C2A "IPL"
FE08+ HCOPY 7C2F "COPY"
FE0D HCMD 7C34 "CMD"
FE12+ HDSKF 7C39 "DSKF"
FE17+ HDSKI 7C3E "DSKI$"
FE1C HATTR 7C43 "ATTR$"
FE21+ HLSET 7C48 "LSET"
FE26+ HRSET 7C4D "RSET"
FE2B+ HFIEL 7C52 "FIELD"
FE30+ HMKI$ 7C57 "MKI$"
FE35+ HMKS$ 7C5C "MKS$"
FE3A+ HMKD$ 7C61 "MKD$"
FE3F+ HCVI 7C66 "CVI"
FE44+ HCVS 7C6B "CVS"
FE49+ HCVD 7C70 "CVD"
FE4E+ HGETP 6A93 Locate FCB
FE53 HSETF 6AB3 Locate FCB
FE58+ HNOFO 6AF6 "OPEN": not found
FE5D+ HNULO 6B0F "OPEN"
FE62+ HNTFL 6B3B Close I/O buffer 0
FE67 HMERG 6B63 "MERGE/LOAD"
FE6C HSAVE 6BA6 "SAVE"
FE71+ HBINS 6BCE "SAVE"
FE76+ HBINL 6BD4 "MERGE/LOAD"
FE7B+ HFILE 6C2F "FILES"
FE80+ HDGET 6C3B "GET/PUT"
FE85+ HFILO 6C51 Sequential output
FE8A+ HINDS 6C79 Sequential input
FE8F HRSLF 6CD8 "INPUT$"
FE94 HSAVD 6D03"LOC",6D14"LOF",6D25"EOF",6D39"FPOS"
FE99+ HLOC 6D0F "LOC"
FE9E+ HLOF 6D20 "LOF"
FEA3+ HEOF 6D33 "EOF"
FEA8 HFPOS 6D43 "FPOS"
FEAD+ HBAKU 6E36 "LINE INPUT#"
FEB2+ HPARD 6F15 Parse device name
FEB7+ HNODE 6F33 Parse device name
FEBC+ HPOSD 6F37 Parse device name
FEC1 HDEVN This hook not used
FEC6 HGEND 6F8F I/O function despatcher
FECB HRUNC 629A Run-clear
FED0 HCLEA 62A1 Run-clear
FED5 HLOPD 62AF Run-clear
FEDA HSTKE 62F0 Reset stack
FEDF HISFL 145F ISFLIO std routine
FEE4 HOUTD 1B46 OUTDO std routine
FEE9 HCRDO 7328 CR,LF to OUTDO
FEEE HDSKC 7374 Mainloop line input
FEF3 HDOGR 593C Line draw
FEF8 HPRGE 4039 Program end
FEFD+ HERRP 40DC Error handler
FF02 HERRF 40FD Error handler
FF07 HREAD 4128 Mainloop "OK"
FF0C HMAIN 4134 Mainloop
FF11 HDIRD 41A8 Mainloop direct statement
FF16 HFINI 4237 Mainloop finished
FF1B HFINE 4247 Mainloop finished
FF20 HCRUN 42B9 Tokenise
FF25 HCRUS 4353 Tokenise
FF2A HISRE 437C Tokenise
FF2F HNTFN 43A4 Tokenise
FF34 HNOTR 44EB Tokenise
FF39 HSNGF 45D1 "FOR"
+/c FF3E+ HNEWS 4601 Runloop new statement
FF43 HGONE 4646 Runloop execute
FF48 HCNRG 4666 CHRGTR std routine
FF4D HRETU 4821 "RETURN"
FF52 HPRTF 4A5E "PRINT"
FF57 HCOMP 4A94 "PRINT"
FF5C HFINP 4AFF "PRINT"
FF61 HTRMN 4B4D "READ/INPUT" error
FF66 HFRME 4C6D Expression Evaluator
FF6B HNTPL 4CA6 Expression Evaluator
FF70 HEVAL 4DD9 Factor Evaluator
FF75 HOKNO 4F2C Factor Evaluator
FF7A HFING 4F3E Factor Evaluator
FF7F HISMI 51C3 Runloop execute
FF84 HWIDT 51CC "WIDTH"
FF89 HLIST 522E "LIST"
FF8E HBUFL 532D Detokenise
FF93 HFRQI 543F Convert to integer
FF98 HSCNE 5514 Line number to pointer
FF9D HFRET 67EE Free descriptor
FFA2 HPTRG 5EA9 Variable search
FFA7+ HPHYD 148A PHYDIO std routine
FFAC+ HFORM 148E FORMAT std routine
FFB1 HERRO 406F Error handler( ÎÁÞÁÌÏ )
FFB6 HLPTO 085D LPTOUT std routine
FFBB HLPTS 0884 LPTSTT std routine
FFC0 HSCRE 79CC "SCREEN"
FFC5 HPLAY 73E5 "PLAY" statement
FFCA EXTBIO: xxxx Used to access external BIOS implementations
FFCF HBGFD before physical operation with disk controller
FFD4 HENFD after physical operation with disk controller
FFE7 RG08SAV Content of VDP(09) register (R#08)
FFE8 RG09SAV Content of VDP(10) register (R#09)
FFE9 RG10SAV Content of VDP(11) register (R#10)
FFEA RG11SAV Content of VDP(12) register (R#11)
FFEB RG12SAV Content of VDP(13) register (R#12)
FFEC RG13SAV Content of VDP(14) register (R#13)
FFED RG14SAV Content of VDP(15) register (R#14)
FFEE RG15SAV Content of VDP(16) register (R#15)
FFEF RG16SAV Content of VDP(17) register (R#16)
FFF0 RG17SAV Content of VDP(18) register (R#17)
FFF1 RG18SAV Content of VDP(19) register (R#18)
FFF2 RG19SAV Content of VDP(20) register (R#19)
FFF3 RG20SAV Content of VDP(21) register (R#20)
FFF4 RG21SAV Content of VDP(22) register (R#21)
FFF5 RG22SAV Content of VDP(23) register (R#22)
FFF6 RG23SAV Content of VDP(24) register (R#23)
FFF7 ROMSLT Slotadress of Main-ROM
FFF8 Reserved
FFFA RG25SAV Content of VDP(26) register (R#25) MSX2+
FFFB RG26SAV Content of VDP(27) register (R#26) MSX2+
FFFC RG27SAV Content of VDP(28) register (R#27) MSX2+
FFFD Temporary stack pointer storage
FFFF SLTSL Secondary slot select register
(Reading returns INVERTED! previous written value)