Search found 1283 matches

by dr beep
Tue May 05, 2020 10:04 am
Forum: Development
Topic: .chr files from Chroma needed for support in SP-2-ZX81
Replies: 2
Views: 231

Re: .chr files from Chroma needed for support in SP-2-ZX81

I found room in my latest emulator to add altered characterset from chroma interface. I do need .chr files ( and the .p) from games to test and convert it. Any files available or should I skip the development? Sounds useful. A number of .chr files for games can be found here , and the game .p files...
by dr beep
Tue May 05, 2020 9:58 am
Forum: GAMES
Topic: RetroSnake is out ! New ZX81 16k Pseudo High Res game
Replies: 13
Views: 891

Re: RetroSnake is out ! New ZX81 16k Pseudo High Res game

mrtinb wrote:
Mon May 04, 2020 11:52 pm
Yes Beep, but then it wouldn't be in C ;-)
Still.... you can use the screenmemory to code a redefine keys routine, only called AFTER loading and then use the memory for the screen as needed.
by dr beep
Mon May 04, 2020 9:08 am
Forum: GAMES
Topic: RetroSnake is out ! New ZX81 16k Pseudo High Res game
Replies: 13
Views: 891

Re: RetroSnake is out ! New ZX81 16k Pseudo High Res game

It plays well on my real ZX81 as well, but no custom keys, is a pain. Sadly I had to squeeze every byte to fit in 16K, the pseudo high res display file alone consumes 6KB. What I could do is release a new version with hardcoded alternative sets of keys, i guess that could take only a few bytes. Any...
by dr beep
Mon May 04, 2020 9:02 am
Forum: Development
Topic: .chr files from Chroma needed for support in SP-2-ZX81
Replies: 2
Views: 231

.chr files from Chroma needed for support in SP-2-ZX81

I found room in my latest emulator to add altered characterset from chroma interface.

I do need .chr files ( and the .p) from games to test and convert it.

Any files available or should I skip the development?

other positive fact; screenupdate is a bit quicker now.
by dr beep
Sun May 03, 2020 9:33 am
Forum: Emulators
Topic: Zeddy emulator for ZX Spectrum
Replies: 13
Views: 4939

Re: Zeddy emulator for ZX Spectrum

It made me think about the ZX81-emulator. I already made a new version that never was released and will never since the code is slower than the original due to contented memory. However if I alter the location of the emulator and set supporting routines in contented memory I will be able to win spe...
by dr beep
Sat May 02, 2020 10:14 pm
Forum: ZX BASIC
Topic: Hidden BASIC lines at end of program space
Replies: 11
Views: 385

Re: Hidden BASIC lines at end of program space

This is the base model I use, even the compressed screen is in its shortest mode by placing the JP (HL) at the last NewLine ; Base model for optimal ZX81 code in lowres ; 12 bytes from #4000 to #400B free reuseble for own "variables" org #4009 ; in LOWRES more sysvar are used, but in this way the sh...
by dr beep
Sat May 02, 2020 10:05 pm
Forum: Emulators
Topic: SP-2-ZX81, the new ZX81-emulator for the 48K ZX Spectrum
Replies: 4
Views: 676

SP-2-ZX81, the new ZX81-emulator for the 48K ZX Spectrum

This is the official release of my NEW ZX81 EMULATOR for the 48K ZX Spectrum.
Fully software and much faster than my emulator from 1997.
The old emulator is also included.
https://www.mediafire.com/file/oiejfzmj ... X.zip/file
by dr beep
Fri May 01, 2020 7:26 pm
Forum: ZX BASIC
Topic: Hidden BASIC lines at end of program space
Replies: 11
Views: 385

Re: Hidden BASIC lines at end of program space

I am coding directly in a compiler and compile to .P My BASIC is always just 1 line, the call to MC only. My MC is stored in every available address. I have placed my BASIC line call to MC fully over the sysvar. My games have autostart. When you would hack the NXTLIN you still don't get a line of BA...
by dr beep
Fri May 01, 2020 7:20 pm
Forum: ZX BASIC
Topic: Execution speed, faster at beginning versus end of long program
Replies: 2
Views: 184

Re: Execution speed, faster at beginning versus end of long program

Yes this is known issue. Your games best have initialize at then end (only called once) and on a ZX Spectrum DEF FN is better place at the start (scanned first) Often used code is best placed high as possible in the listings. Machinecode will just execute what is at the Program Counter and always po...
by dr beep
Thu Apr 30, 2020 10:07 pm
Forum: ZX BASIC
Topic: Hidden BASIC lines at end of program space
Replies: 11
Views: 385

Re: Hidden BASIC lines at end of program space

It is UDG (user defined graphics) emulated with WRX hires graphics (Wilf Rigter graphic). (WRX requires a hardware modification to your RAMpack.) One thing that is different is that you are not really hiding basic lines. You just have a huge REM at line 0 and all of your BASIC code comes after. The...