                   CC999 invitation dentro.
                          TAP version

                   (c) Digital Reality'1999

                         1. Some words
                         
   I  want  to say some words about this dentro. It is released
into  2  versions:  for  TR-DOS and for other operating systems
(into  TAP  format). TAP version is a bit different from TR-DOS
version, but all removed things are TR-DOS specific. But anyway
you don't lost anything by using this version of dentro.

                     2. About compatibility

   This   version  is  created  especially  to  port  to  other
operating  systems.  This  menas  that  this  version  will  be
probably  run on firm Speccy. And there is the always problem -
compatibility with firm Speccy limitations.
   First  of  all  you  must  know that all codes are developed
using  real  Pentagon 512 and fully tested only on Pentagon and
Scorpion. Both these machines are has no slow memory at all. So
I  can't  guarantee  that  there  will  be no slow down on firm
Speccys, because I has no chance to test and debug code on it.
   But anyway I always remember about firm Speccy users and try
to write the most compatible code. So this code has some things
that  will  (theoretically) makes him more compatible with firm
Speccy:
1)  All  main  demo  codes are placed into fast memory (pages 2
and  0).  The  only  pieces of code are stored into slow memory
(because there are no free other :) )
 - HRUST depacker
 - Demo manager
 - IM2 manager(but IM2 table is always stored into fast memory)
2)  All  stack-based  routines  are  protected  by  special IM2
checker or by interrupt-disabling. The only part which probably
can  make  music  playing  slow  - 'glass' (it runs after first
messager).  I  think  that  there  is  no chance to get a reset
during demo.
3) Demo syncronization system (developed special for this demo)
featured  absolutely  correct  syncronization with music on all
machines  (only theoretically, but it seems to be true :) ), so
there probably will be no problems with it.
4)  All  memory banks switching are use out to full #7FFD port,
no other ports is using.
5)  Demo  is  always  correct system registers (HL', IY, I), so
there probably will be no problems with BASIC loader.
6)  Demo  used  areas  #5B00-#5BFF  to store HRUST depacker and
#6000-#FFFF to main code. No any corruption of BASIC area.

                        3. Requirements

 - Demo  requires at least 128kb of memory. There is  NO chance
to run it on 48k.
 - Music chip is required (AY or YM)
 - To  correct  work  is required to run demo with 48k ROM, but
with  open  #7FFD port. This can be done by type USR 0 into 128
BASIC or by reset 4 bit into FLAGS variable (23611, #5C3B)
 - TR-DOS v5.03 or later is required only into TR-DOS version.
 - Demo is NOT tested into turbo mode, but all seems to be OK.
 - The best results will be on machines with NO slow memory.

                          4. Contacts

   All contact adresses with CC999 organizers you can find into
CC999  rules.  Latest  version  of rules can be downloaded from
official CC999 web site: cc999.da.ru
   
   If you want to contact with autors of this invitation:
email: hirez@ngts.telecom.nov.ru (for all common questions)
       flying@ngts.telecom.nov.ru (for technical questions,
                                   bugreports, etc)
ICQ: 32398105
IRC: #z80 under nick Flying^DR or Flying
