Sinclair zx spectrum emulator free#

After a lot of swaping and re-coding, iвЂ™ve managed to get the speed up to a much more impressive 210%/168%.

Obviously there was something seriously wrong in the display routines. The speed jumped up to a massive 495%/312% (BASIC/Cobra)! With this in mind, I tried disabling them so I could just measure the speed of the CPU core. I had put them togetherВ with aВ вЂjust get it workingвЂ™ attitude and I knew that there were savings to be had. I knew that my display routines were not the best in the world. When under load (I used the menu screen of Cobra), the speed fell to 116%. When idling in Spectrum BASIC, SpeccyDS ran at 134% of a real Spectrum. Therefore, I added a simple speed meter that displays the percentage speed when compared to a real Spectrum. Over the last few weeks iвЂ™ve been looking into how fast SpeccyDS currently runs and how it can be optomised to handle some of the new features. Any amountВ is gratefully received! Thank youВ рџ™‚ If you are feeling generous, please show your appreciation by donating aВ few poundsВ towards the project.

Sinclair zx spectrum emulator free#

Developing SpeccyDS takes up a large amount of my free time. IвЂ™ve also added a Donate tab at the top of the blog. It was caused by a silly bug in the HALT instruction However, the sound still cuts out in some rooms вЂ“ Fixed the flags on the DAA instruction to fix Head Over Heals. Sound is now produced when using the BASIC saveВ command etc вЂ“ Simulated the resistor connection between the EAR and MIC ports on the spectrum. Z80 files should now be accepted without causing the Spectrum to reset The thin border should keep the distortion down to a minimum.ДЄ few other things have changed, including: Therefore, I will probably add three border settings вЂ“В None (default), Thin and Full. Luckily, the DS hardware makes screen scaling very simple. The second shot demonstrates the scaling problems that are associated with displaying the borders on such a small screen. The first screenshot is the result of a BASIC Save command and demonstrates the border quite well. Over the last week IвЂ™ve used this to hook up proper border emulation: In my last post I explained how I had changed the display routines to speed up SpeccyDS and allow me to do some more interesting stuff with the screen.

Hopefully the new version will be out in the next couple of weeks! I may change it in the future depending on how people feel about it.ДЄll this means that V0.3 has started to appear on the horizon! I havenвЂ™t touched any of the actual emulation side of things so far for this release, so it would be nice if I can at least implement the remaining undocumented Z80 flags to get Ghosts вЂnвЂ™ Goblins working. I was thinking about saving them back to individual config files based on the game that is loaded but it might be a bit confusing to configure. The settings, including the defined controls, are saved back to the flash card to a single config file. I was going to draw a keyboard for each of the Spectrum models, but since they are pretty much the same for the later models I havenвЂ™t bothered for the time being. IвЂ™ve included a graphic of the +2 keyboard alongВ with the original 48K keyboard. Re-definable keyboard controls are included, along with a settings menu to let you define the border size and the keyboard graphic to be displayed. Finally, afterВ spending the oddВ freeВ hourВ on it over the last few weeks, the GUI rewrite is done.