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15-01-88/T\SWR12

This website contains an archive of files for the Acorn Electron, BBC Micro, Acorn Archimedes, Commodore 16 and Commodore 64 computers, which Dominic Ford has rescued from his private collection of floppy disks and cassettes.

Some of these files were originally commercial releases in the 1980s and 1990s, but they are now widely available online. I assume that copyright over them is no longer being asserted. If you own the copyright and would like files to be removed, please contact me.

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Filename: 15-01-88/T\SWR12
Read OK:
File size: 3D64 bytes
Load address: 0000
Exec address: FFFFFFFF
Duplicates

There is 1 duplicate copy of this file in the archive:

File contents
Mastering Sideways ROM & RAM - Module 12 - Absolute workspace
-------------------------------------------------------------

  Private workspace is exclusive to the rom claiming it. Absolute
workspace can also be claimed by paged roms. Absolute workspace,
unlike private workspace, is a single block of memory which is shared
between all the roms but is only allocated to one rom at a time.

  Absolute workspace can be claimed in user memory when it runs from
&E00 to the highest address asked for by any of the roms. The Master
computer can also claim the alternative paged memory absolute
workspace. Claiming and using paged memory absolute workspace will be
explained after dealing with user memory absolute workspace.

  In order to claim absolute workspace your SWR interpreter has to
intercept the absolute workspace service call. To demonstrate the
absolute workspace service call load the object code generated by the
program TRACE into SWR and press the Break key (Ctrl+Break on the
Master). A list of service calls similar to the one in figure 12.1
will be printed on the screen. Unless you use a BBC B with an Acorn
6502 Second Processor, Acorn DNFS and sideways ram in socket &0F your
trace will be different from the one in figure 12.1, but in all BBC
computers you will find service call 1, the absolute workspace claim,
somewhere in the list.




 A=19 X=0F Y=FF SPOOL/EXEC file closure
 A=0F X=0F Y=FF Vectors claimed
 A=FF X=0F Y=FF Tube system main init.
 A=01 X=0F Y=0E Abs. workspace claim
 A=02 X=0F Y=17 Private workspace claim
 A=FE X=0F Y=FF Tube system post init.
 A=11 X=0F Y=1F Font implode/explode

Acorn TUBE 6502 64K

 A=03 X=0F Y=08 Auto-boot
Acorn DFS

 A=10 X=0F Y=EE SPOOL/EXEC file closure
 A=0F X=0F Y=30 Vectors claimed
 A=0A X=0F Y=D4 Claim static workspace
BASIC

>

Figure 12.1  Service call trace after Break
-------------------------------------------



  In figure 12.1 you can see that the absolute workspace claim,
service call 1, is made with Y=&0E. This indicates that no absolute
workspace has yet been claimed. If the trace is run from a lower
priority rom than the Acorn DFS rom then service call 1 is made with
Y=&17 indicating that 9 pages of absolute workspace are claimed by the
DFS.

  When service call 1 is made the Y register contains the current
upper limit of the absolute workspace. This starts at &0E and each rom
should compare the value in the Y register with the upper limit of
absolute workspace required by the rom and, if necessary, increase it
to the level required by the rom. Your software must never decrement
the Y register when it intercepts either service call 1 or 2.

  In order to use the absolute workspace effectively it is necessary
for your SWR program to claim private workspace as well. One reason
for this is that your rom will need to keep a flag indicating whether
or not it has control of the absolute workspace. This flag should be
located in private workspace. It is also a good idea to keep a copy of
any vital data from absolute workspace in private workspace where you
can be sure that it will not be corrupted. If you intend to write SWR
software that uses absolute workspace you should think of the absolute
workspace as a temporary extension to the private workspace and not as
a substitute for private workspace.

  When you want your rom to use the absolute workspace it has to issue
service call &0A to inform the other roms of its intention. Service
call &0A is issued by calling Osbyte &8F with X = service type and
Y = argument for service. In this case make X=&0A and Y=&FF. The rom
is then free to use the absolute workspace and the zero page locations
from &B0 to &CF until its interpreter intercepts a service call &0A
issued by another rom. The interpreter must intercept service call &0A
which instructs it to release the absolute workspace to the rom
issuing the call, usually the DFS.

  I have not written an example program which uses absolute workspace
but I have included a outline program, ABSOL, which includes all the
coding you need to write your own.

  ABSOL intercepts service call 1 to claim absolute workspace, service
call 2 to claim private workspace, sevice call &0A to release absolute
workspace, and service call 4 to recognise the new * command *STATIC.
It uses the one-command interpreter (lines 570-780) used in the
earlier modules of the course.

  The example program ABSOL ensures that at least one page of absolute
workspace is available (lines 300-360) and claims one page of private
workspace (lines 410-450). These are the minimum meaningful amounts if
the program is to use absolute workspace.

  The program recognises service call &0A (lines 470-500). After
recognising service call &0A the program would have to copy any vital
data from absolute to private workspace and adjust a flag kept in
private workspace to indicate that it no longer had control of the
absolute workspace.

  When the interpreter recognises the new command *STATIC it issues
service call &0A (lines 800-830) to inform the other roms that it
intends to use the absolute workspace. When it has control of the
absolute workspace it can also use the zero page locations from &B0 to
&CF, but it must be prepared to give up control of both these zero
page locations and the absolute workspace when the interpreter
intercepts a service call &0A issued by another rom.

  Although using absolute workspace is fairly straightforward if you
use this outline program, it is an unnecessary complication if you
really don't need it. You will probably only need to use it if your
program uses large amounts of data for a short time.





   10 REM: ABSOL
   20 MODE7
   30 HIMEM=&3C00
   40 DIM save 50
   50 diff=&8000-HIMEM
   60 address=&70
   70 comvec=&F2
   80 romnumber=&F4
   90 workspace=&DF0
  100 gsread=&FFC5
  110 osbyte=&FFF4
  120 oscli=&FFF7
  130 FOR pass = 0 TO 2 STEP 2
  140 P%=HIMEM
  150 [       OPT pass
  160         BRK
  170         BRK
  180         BRK
  190         JMP service+diff
  200         OPT FNequb(&82)
  210         OPT FNequb((copyright+diff) MOD 256)
  220         BRK
  230 .title
  240         OPT FNequs("STATIC")
  250 .copyright
  260         BRK
  270         OPT FNequs("(C) Gordon Horsington 1987")
  280         BRK
  290 .service
  300         CMP #1
  310         BNE trytwo
  320         CPY #&0F
  330         BCS carryon
  340         INY           \ claim 1 page of abs. workspace
  350 .carryon
  360         RTS
  370 .trytwo
  380         PHA
  390         CMP #2
  400         BNE tryten
  410         TYA
  420         STA workspace,X
  430         INY           \ 256 bytes of private workspace
  440         PLA
  450         RTS
  460 .tryten
  470         CMP #&0A
  480         BNE tryfour
  490                       \ Prepare to release
  500                       \ absolute workspace
  510 .enough
  520         PLA
  530         RTS
  540 .tryfour
  550         CMP #4
  560         BNE enough
  570         TXA
  580         PHA
  590         TYA
  600         PHA
  610         LDX #&FF
  620 .comloop
  630         INX
  640         LDA title+diff,X
  650         BEQ found
  660         LDA (comvec),Y
  670         INY
  680         CMP #ASC(".")
  690         BEQ found
  700         AND #&DF
  710         CMP title+diff,X
  720         BEQ comloop
  730         PLA
  740         TAY
  750         PLA
  760         TAX
  770         PLA
  780         RTS
  790 .found
  800         LDA #&8F
  810         LDX #&0A      \ service call &0A
  820         LDY #&FF
  830         JSR osbyte    \ Claim absolute workspace
  840                       \ Use zero page from &B0 to &CF
  850                       \ and absolute workspace as well
  860                       \ as private workspace.
  870         PLA
  880         PLA
  890         PLA
  900         LDA #0
  910         RTS
  920 .lastbyte
  930 ]
  940 NEXT
  950 INPUT'"Save filename? : "filename$
  960 IF filename$="" END
  970 $save="SAVE "+filename$+" "+STR$~(HIMEM)+" "+STR$~(las
      tbyte)+" FFFF8000 FFFF8000"
  980 X%=save MOD 256
  990 Y%=save DIV 256
 1000 *OPT1,2
 1010 CALL oscli
 1020 *OPT1,0
 1030 END
 1040 DEFFNequb(byte)
 1050 ?P%=byte
 1060 P%=P%+1
 1070 =pass
 1080 DEFFNequw(word)
 1090 ?P%=word MOD 256
 1100 P%?1=word DIV 256
 1110 P%=P%+2
 1120 =pass
 1130 DEFFNequd(double)
 1140 !P%=double
 1150 P%=P%+4
 1160 =pass
 1170 DEFFNequs(string$)
 1180 $P%=string$
 1190 P%=P%+LEN(string$)
 1200 =pass



  In order to use the alternative paged memory absolute workspace on
the Master computer it is necessary to intercept service call &23
instead of service call 1. Your program must not claim user memory
absolute workspace as well as paged memory absolute workspace.

  Paged memory absolute workspace in the Master starts at &C000 and
has an upper limit of &DBFF. The upper limit of the absolute workspace
must not exceed &DBFF under any circumstances.

  If you intend to use paged memory absolute workspace the outline
program ABSOL will need to be modified. The interpreter will no longer
need to intercept service calls 1 and 2 but it will need to intercept
service call &23 to claim paged memory absolute workspace and service
calls &24 and &22 to claim paged memory private workspace. Suitable
modifications for ABSOL are shown in figure 12.2



.service
        CMP #&23      \ paged absolute workspace claim?
        BNE try24     \ branch if no
        CPY #&C1      \ is 1 page already available?
        BCS carryon   \ branch if yes
        INY           \ claim 1 page of absolute workspace
.carryon
        RTS
.try24
        CMP #&24      \ paged private workspace claim?
        BNE try22     \ branch if no
        INY           \ request 1 page of private workspace
        RTS
.try22
        CMP #&22      \ paged private workspace claim?
        BNE try10     \ branch if no
        PHA           \ store accumulator
        TYA           \ most sig. byte of start address
        STA &DF0,X    \ store start of private workspace
        PLA           \ restore accumulator
        RTS
.try10


Figure 12.2 Modificatins needed for the Master
----------------------------------------------


  In Module 11 I explained how to switch the paged workspace memory in
and out of the main memory map. It is necessary to use the same
techniques described in Module 11 when using paged memory absolute
workspace.

  Before attempting to read or write the contents of the paged memory
absolute workspace, the SWR program must first set bit 3 of the paged
memory select register at &FE34 to switch the paged memory into the
main memory map. To set bit 3 of &FE34 load the accumulator with &08
(0000 1000 binary), OR the accumulator with the contents of &FE34 and
store the accumulator in &FE34.

  To switch the paged memory absolute workspace out of the main memory
map it is necessary to clear bit 3 of the paged memory select
register. To clear bit 3 of &FE34 load the accumulator with &F7 (1111
0111 binary), AND the accumulator with the contents of &FE34 and store
the accumulator in &FE34. If you use the subroutines illustrated in
figure 12.3 the paged memory can be switched in and out of the main
memory map without altering any of the other bits in the paged memory
select register.




         JSR pagein      \ switch paged workspace in
         LDA &C000       \ Read first byte of absolute workspace
         JSR pageout     \ switch paged workspace out
          .
          .
          .
.pagein
         PHA
         LDA #8          \ 0000 1000 binary
         ORA &FE34
         STA &FE34       \ set bit 3 of &FE34
         PLA             \ restore accumulator
         RTS
.pageout
         PHA
         LDA #&F7        \ 1111 0111 binary
         AND &FE34
         STA &FE34       \ clear bit 3 of &FE34
         PLA             \ restore accumulator
         RTS


Figure 12.3  Reading paged absolute workspace on the Master.
-----------------------------------------------------------

  Figure 12.3 illustrates how the two subroutines, pagein and pageout,
should be used to switch the paged memory in and out of the main
memory map when reading the contents of the paged memory absolute
workspace in the Master series computers. Unlike private workspace,
absolute workspace always has a fixed start address and can be
addressed directly.

  After switching the paged memory into the main memory map you must
be very careful about using MOS subroutines because the bottom 7.25k
of the MOS has been replaced with the paged memory. You would be wise
not to use the MOS at all until it has been restored by calling
pageout.

  The "legal" use of service call 1 has been explained above but a
much more common "illegal" use is also made of this service call.

  Look again at figure 12.1, the list of service calls issued after
pressing the Break key. Some of these calls, including service call 1,
are always issued on the BBC B when the Break key is pressed and also
when the computer is switched on. (Service call 1 is only issued on
Ctrl-Break on the Master but service call &FE can be used instead
because it is always issued when the Break key is pressed on the
Master computer). Service call 1 or service call &FE can be
intercepted to carry out almost any function required at reset if, and
only if, all the registers are preserved.

  Imagine, for example, that you want the video interlace to stay
switched off. Your SWR interpreter could intercept service call 1 (or
&FE), push all the registers on the stack, switch off the interlace,
pull all the registers back off the stack and return control to the
MOS. This idea has been implemented in the program INTLACE.

  Load the object code generated by INTLACE into SWR, press the Break
key and select Mode 6. The interlace will remain switched off until
you select Mode 7 or press Ctrl+Break. It will switch back off when
you next select one of the modes 0-6.

  This type of illegal use of service call 1 (or &FE) will be used
again in Module 22 when designing the software for auto-booting rom
cartridges is covered. It will be used then to ensure that the rom
cartridge is always the language booted after a soft reset.



   10 REM: INTLACE
   20 MODE7
   30 HIMEM=&3C00
   40 DIM save 50
   50 diff=&8000-HIMEM
   60 osbyte=&FFF4
   70 oscli=&FFF7
   80 FOR pass = 0 TO 2 STEP 2
   90 P%=HIMEM
  100 [       OPT pass
  110         BRK
  120         BRK
  130         BRK
  140         JMP service+diff
  150         OPT FNequb(&82)
  160         OPT FNequb((copyright+diff) MOD 256)
  170         BRK
  180         OPT FNequs("INTERLACE")
  190 .copyright
  200         BRK
  210         OPT FNequs("(C) Gordon Horsington 1987")
  220         BRK
  230 .service
  240         CMP #&FE
  250         BEQ autoboot
  260         RTS
  270 .autoboot
  280         PHA
  290         TXA
  300         PHA
  310         TYA
  320         PHA
  330         LDA #&90
  340         LDX #&FF
  350         LDY #1
  360         JSR osbyte    \ *TV255,1
  370         PLA
  380         TAY
  390         PLA
  400         TAX
  410         PLA
  420         RTS
  430 .lastbyte
  440 ]
  450 NEXT
  460 INPUT'"Save filename = "filename$
  470 IF filename$="" END
  480 $save="SAVE "+filename$+" "+STR$~(HIMEM)+" "+STR$~(las
      tbyte)+" FFFF8000 FFFF8000"
  490 X%=save MOD 256
  500 Y%=save DIV 256
  510 *OPT1,2
  520 CALL oscli
  530 *OPT1,0
  540 END
  550 DEFFNequb(byte)
  560 ?P%=byte
  570 P%=P%+1
  580 =pass
  590 DEFFNequw(word)
  600 ?P%=word MOD 256
  610 P%?1=word DIV 256
  620 P%=P%+2
  630 =pass
  640 DEFFNequd(double)
  650 !P%=double
  660 P%=P%+4
  670 =pass
  680 DEFFNequs(string$)
  690 $P%=string$
  700 P%=P%+LEN(string$)
  710 =pass
00000000  4d 61 73 74 65 72 69 6e  67 20 53 69 64 65 77 61  |Mastering Sidewa|
00000010  79 73 20 52 4f 4d 20 26  20 52 41 4d 20 2d 20 4d  |ys ROM & RAM - M|
00000020  6f 64 75 6c 65 20 31 32  20 2d 20 41 62 73 6f 6c  |odule 12 - Absol|
00000030  75 74 65 20 77 6f 72 6b  73 70 61 63 65 0d 2d 2d  |ute workspace.--|
00000040  2d 2d 2d 2d 2d 2d 2d 2d  2d 2d 2d 2d 2d 2d 2d 2d  |----------------|
*
00000070  2d 2d 2d 2d 2d 2d 2d 2d  2d 2d 2d 0d 0d 20 20 50  |-----------..  P|
00000080  72 69 76 61 74 65 20 77  6f 72 6b 73 70 61 63 65  |rivate workspace|
00000090  20 69 73 20 65 78 63 6c  75 73 69 76 65 20 74 6f  | is exclusive to|
000000a0  20 74 68 65 20 72 6f 6d  20 63 6c 61 69 6d 69 6e  | the rom claimin|
000000b0  67 20 69 74 2e 20 41 62  73 6f 6c 75 74 65 0d 77  |g it. Absolute.w|
000000c0  6f 72 6b 73 70 61 63 65  20 63 61 6e 20 61 6c 73  |orkspace can als|
000000d0  6f 20 62 65 20 63 6c 61  69 6d 65 64 20 62 79 20  |o be claimed by |
000000e0  70 61 67 65 64 20 72 6f  6d 73 2e 20 41 62 73 6f  |paged roms. Abso|
000000f0  6c 75 74 65 20 77 6f 72  6b 73 70 61 63 65 2c 0d  |lute workspace,.|
00000100  75 6e 6c 69 6b 65 20 70  72 69 76 61 74 65 20 77  |unlike private w|
00000110  6f 72 6b 73 70 61 63 65  2c 20 69 73 20 61 20 73  |orkspace, is a s|
00000120  69 6e 67 6c 65 20 62 6c  6f 63 6b 20 6f 66 20 6d  |ingle block of m|
00000130  65 6d 6f 72 79 20 77 68  69 63 68 20 69 73 20 73  |emory which is s|
00000140  68 61 72 65 64 0d 62 65  74 77 65 65 6e 20 61 6c  |hared.between al|
00000150  6c 20 74 68 65 20 72 6f  6d 73 20 62 75 74 20 69  |l the roms but i|
00000160  73 20 6f 6e 6c 79 20 61  6c 6c 6f 63 61 74 65 64  |s only allocated|
00000170  20 74 6f 20 6f 6e 65 20  72 6f 6d 20 61 74 20 61  | to one rom at a|
00000180  20 74 69 6d 65 2e 0d 0d  20 20 41 62 73 6f 6c 75  | time...  Absolu|
00000190  74 65 20 77 6f 72 6b 73  70 61 63 65 20 63 61 6e  |te workspace can|
000001a0  20 62 65 20 63 6c 61 69  6d 65 64 20 69 6e 20 75  | be claimed in u|
000001b0  73 65 72 20 6d 65 6d 6f  72 79 20 77 68 65 6e 20  |ser memory when |
000001c0  69 74 20 72 75 6e 73 20  66 72 6f 6d 0d 26 45 30  |it runs from.&E0|
000001d0  30 20 74 6f 20 74 68 65  20 68 69 67 68 65 73 74  |0 to the highest|
000001e0  20 61 64 64 72 65 73 73  20 61 73 6b 65 64 20 66  | address asked f|
000001f0  6f 72 20 62 79 20 61 6e  79 20 6f 66 20 74 68 65  |or by any of the|
00000200  20 72 6f 6d 73 2e 20 54  68 65 20 4d 61 73 74 65  | roms. The Maste|
00000210  72 0d 63 6f 6d 70 75 74  65 72 20 63 61 6e 20 61  |r.computer can a|
00000220  6c 73 6f 20 63 6c 61 69  6d 20 74 68 65 20 61 6c  |lso claim the al|
00000230  74 65 72 6e 61 74 69 76  65 20 70 61 67 65 64 20  |ternative paged |
00000240  6d 65 6d 6f 72 79 20 61  62 73 6f 6c 75 74 65 0d  |memory absolute.|
00000250  77 6f 72 6b 73 70 61 63  65 2e 20 43 6c 61 69 6d  |workspace. Claim|
00000260  69 6e 67 20 61 6e 64 20  75 73 69 6e 67 20 70 61  |ing and using pa|
00000270  67 65 64 20 6d 65 6d 6f  72 79 20 61 62 73 6f 6c  |ged memory absol|
00000280  75 74 65 20 77 6f 72 6b  73 70 61 63 65 20 77 69  |ute workspace wi|
00000290  6c 6c 20 62 65 0d 65 78  70 6c 61 69 6e 65 64 20  |ll be.explained |
000002a0  61 66 74 65 72 20 64 65  61 6c 69 6e 67 20 77 69  |after dealing wi|
000002b0  74 68 20 75 73 65 72 20  6d 65 6d 6f 72 79 20 61  |th user memory a|
000002c0  62 73 6f 6c 75 74 65 20  77 6f 72 6b 73 70 61 63  |bsolute workspac|
000002d0  65 2e 0d 0d 20 20 49 6e  20 6f 72 64 65 72 20 74  |e...  In order t|
000002e0  6f 20 63 6c 61 69 6d 20  61 62 73 6f 6c 75 74 65  |o claim absolute|
000002f0  20 77 6f 72 6b 73 70 61  63 65 20 79 6f 75 72 20  | workspace your |
00000300  53 57 52 20 69 6e 74 65  72 70 72 65 74 65 72 20  |SWR interpreter |
00000310  68 61 73 20 74 6f 0d 69  6e 74 65 72 63 65 70 74  |has to.intercept|
00000320  20 74 68 65 20 61 62 73  6f 6c 75 74 65 20 77 6f  | the absolute wo|
00000330  72 6b 73 70 61 63 65 20  73 65 72 76 69 63 65 20  |rkspace service |
00000340  63 61 6c 6c 2e 20 54 6f  20 64 65 6d 6f 6e 73 74  |call. To demonst|
00000350  72 61 74 65 20 74 68 65  0d 61 62 73 6f 6c 75 74  |rate the.absolut|
00000360  65 20 77 6f 72 6b 73 70  61 63 65 20 73 65 72 76  |e workspace serv|
00000370  69 63 65 20 63 61 6c 6c  20 6c 6f 61 64 20 74 68  |ice call load th|
00000380  65 20 6f 62 6a 65 63 74  20 63 6f 64 65 20 67 65  |e object code ge|
00000390  6e 65 72 61 74 65 64 20  62 79 20 74 68 65 0d 70  |nerated by the.p|
000003a0  72 6f 67 72 61 6d 20 54  52 41 43 45 20 69 6e 74  |rogram TRACE int|
000003b0  6f 20 53 57 52 20 61 6e  64 20 70 72 65 73 73 20  |o SWR and press |
000003c0  74 68 65 20 42 72 65 61  6b 20 6b 65 79 20 28 43  |the Break key (C|
000003d0  74 72 6c 2b 42 72 65 61  6b 20 6f 6e 20 74 68 65  |trl+Break on the|
000003e0  0d 4d 61 73 74 65 72 29  2e 20 41 20 6c 69 73 74  |.Master). A list|
000003f0  20 6f 66 20 73 65 72 76  69 63 65 20 63 61 6c 6c  | of service call|
00000400  73 20 73 69 6d 69 6c 61  72 20 74 6f 20 74 68 65  |s similar to the|
00000410  20 6f 6e 65 20 69 6e 20  66 69 67 75 72 65 20 31  | one in figure 1|
00000420  32 2e 31 0d 77 69 6c 6c  20 62 65 20 70 72 69 6e  |2.1.will be prin|
00000430  74 65 64 20 6f 6e 20 74  68 65 20 73 63 72 65 65  |ted on the scree|
00000440  6e 2e 20 55 6e 6c 65 73  73 20 79 6f 75 20 75 73  |n. Unless you us|
00000450  65 20 61 20 42 42 43 20  42 20 77 69 74 68 20 61  |e a BBC B with a|
00000460  6e 20 41 63 6f 72 6e 0d  36 35 30 32 20 53 65 63  |n Acorn.6502 Sec|
00000470  6f 6e 64 20 50 72 6f 63  65 73 73 6f 72 2c 20 41  |ond Processor, A|
00000480  63 6f 72 6e 20 44 4e 46  53 20 61 6e 64 20 73 69  |corn DNFS and si|
00000490  64 65 77 61 79 73 20 72  61 6d 20 69 6e 20 73 6f  |deways ram in so|
000004a0  63 6b 65 74 20 26 30 46  20 79 6f 75 72 0d 74 72  |cket &0F your.tr|
000004b0  61 63 65 20 77 69 6c 6c  20 62 65 20 64 69 66 66  |ace will be diff|
000004c0  65 72 65 6e 74 20 66 72  6f 6d 20 74 68 65 20 6f  |erent from the o|
000004d0  6e 65 20 69 6e 20 66 69  67 75 72 65 20 31 32 2e  |ne in figure 12.|
000004e0  31 2c 20 62 75 74 20 69  6e 20 61 6c 6c 20 42 42  |1, but in all BB|
000004f0  43 0d 63 6f 6d 70 75 74  65 72 73 20 79 6f 75 20  |C.computers you |
00000500  77 69 6c 6c 20 66 69 6e  64 20 73 65 72 76 69 63  |will find servic|
00000510  65 20 63 61 6c 6c 20 31  2c 20 74 68 65 20 61 62  |e call 1, the ab|
00000520  73 6f 6c 75 74 65 20 77  6f 72 6b 73 70 61 63 65  |solute workspace|
00000530  20 63 6c 61 69 6d 2c 0d  73 6f 6d 65 77 68 65 72  | claim,.somewher|
00000540  65 20 69 6e 20 74 68 65  20 6c 69 73 74 2e 0d 0d  |e in the list...|
00000550  0d 0d 0d 20 41 3d 31 39  20 58 3d 30 46 20 59 3d  |... A=19 X=0F Y=|
00000560  46 46 20 53 50 4f 4f 4c  2f 45 58 45 43 20 66 69  |FF SPOOL/EXEC fi|
00000570  6c 65 20 63 6c 6f 73 75  72 65 0d 20 41 3d 30 46  |le closure. A=0F|
00000580  20 58 3d 30 46 20 59 3d  46 46 20 56 65 63 74 6f  | X=0F Y=FF Vecto|
00000590  72 73 20 63 6c 61 69 6d  65 64 0d 20 41 3d 46 46  |rs claimed. A=FF|
000005a0  20 58 3d 30 46 20 59 3d  46 46 20 54 75 62 65 20  | X=0F Y=FF Tube |
000005b0  73 79 73 74 65 6d 20 6d  61 69 6e 20 69 6e 69 74  |system main init|
000005c0  2e 0d 20 41 3d 30 31 20  58 3d 30 46 20 59 3d 30  |.. A=01 X=0F Y=0|
000005d0  45 20 41 62 73 2e 20 77  6f 72 6b 73 70 61 63 65  |E Abs. workspace|
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*
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*
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00003d60  61 73 73 0d                                       |ass.|
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