Information about the new QDOS version RK00 = Vers. 2.00
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Corrected Bugs:

1) The ERR_DF bug is corrected

2) The TRA table may now work in both directions (I have only removed
   one fatal Bug, but not tested the routine)

3) EPROMs should no more hang up the Booting process.


Improvements:

1) The NMI (<ctrl.> <Alt> <7>) can now be used to resume the Machine
   from fatal system hang up. It Restores BASICs A6 and A7, sets its
   Priority to 32, releases the Job and continues Execution at the
   Warmstart address.

2) you can now BREAK out of EXEC_W programms

3) The Memory test occurs only after switching on the Machine, or
   after a complete and destructive system crash.
   The Command SYS_RESET n (n>=64*1024) resets the computer and
   uses only n bytes of Memory. THIS AMOUNT CONTINUES EVEN AFTER THE
   NEXT RESET !!! The Memory above this limit is NEVER touched in
   any way by the operating system. This makes it possible to have
   RESET resistent procedures in RAM

4) EPROMs are recognized at $10000, and from $40000 on in steps of
   256 bytes. This makes it possible to test the code for EPROMs in RAM.

5) A searchlist for OPEN old files is established. The order of Search
   is : RAM1_, RAM2_, FLP1_, FLP2_, MDV1_, MDV2_ .
   The command CLR_SEALST may be used to switch off this option.

6) The Commands OV_OFF and OV_ON may be used to switch the Overflow
   error in Floatingpoint arithmetics on and off


Extensions to System variables:

1) The Location $28002 contains a Flag byte.
   Bit 0 is used by the Searchlist. If this bit is set, the Searchlist
      is switched off
   Bit 1 is used in Floatingpoint arithmetics. If this bit is set, the
      Overflow error is switched off.

2) A scratch area of 1k memory is allocated in the RESPR area.
   The Pointer to this area is generated as follows:

   MOVE.L   $28020,A0 ; get top of RAM
   SUBA.L   #$400,A0 ; subtract 1k scratch area

   This area is divided into three parts:

   $000 - $0FF is a scratch buffer, used by the OPEN call
   $100 - $1FF may contain additional system variables in future versions
   $200 - $3FF is free for user applications

3) Additional system variables:

   $100.F : X-low in actual picture (6-bytes)
   $106.F : X-high in actual picture (6-bytes)
   $10C.F : Y-low in actual picture (6-bytes)
   $112.F : Y-high in actual picture (6-bytes)
   $118.B : X-flag: =0 -> linear scale, =1 -> log. scale
   $119.B : Y-flag: =0 -> linear scale, =1 -> log. scale
   $11A.L : pointer to high resolution graphics RAM (for Printer)
   $11E.W : Pixel in X-direction for High res graph
   $120.W : Pixel in Y-direction for High res graph
   $122.B : flag: =0 -> no high res mode, =1 -> high res mode is on
   $123.B : actual plotting symbol and size (4bit sym, 4bit siz)
   $124   : string to initialize printer (1 byte length & 11 chars)
   $130   : string to send for graphic mode (1 byte length & 7 chars)
   $138   : string to send for half pixel LF and graphic
   $140   : String to reset printer (1 byte length & 7 chars)

Rainer Kowallik
Eisackstr. 14
1000 Berlin 62