omega wrote: > Hello all, > > I want to present kind of "demo" for QL on the retro-computing > competition called Forever see: http://forever.zeroteam.sk > I did some graphics already on PC and it looks good (looks cool in fact > :-). But, I need to write special screen hadler with following conditions: > > 1) I need to use both screens of the QL without affecting of the 2nd > screen by system variables. > (if there must be some variables, how much is the minimum for > functionality interrupt handler?) > 2) I still need to call my routine every interrupt (50/60Hz) > 3) It must run on unexpanded QL with standard QDOS (sandyQboard > optional), no aurora, no Q40, Q60, no (S)GC. Plain, pure, virging QL only. > 4) Safe return to Qdos is not required.
> > Anyone has any idea if it's possible? Have you/can you get your paws on a copy of the Advanced QL User Guide by Adrian Dickens (ISBN 0 947929 00 2)? On Pg 289-292 [of my copy] is a description of the second screen on the QL plus an assembler program to add pSeudoBASIC extensions to toggle the display. It notes that the system variables splat over the top 1/5(ish) of the screen 1 and so keeps screen 0 displaying the top 1/5(ish) and then displays the required screen (0/1) for the bottom 4/5(ish). The active code allocates 0x6be0 bytes from the common heap which should be allocated in the memory screen 1 uses (to prevent any other program getting it). It then uses a routine added to the 50/60Hz interrupt to switch screens as required. -- --------------------------------------------------------------------------- Robert Newson, E-Mail: [EMAIL PROTECTED] 17 Sunnybank, South Norwood Phone: (020) 8654 6643 London, SE25 4TQ Mobile: 07737 515 214 or 07922 060 873 _______________________________________________ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
