SpeccyDS News

News of the work on the Spectrum emulator for the DS by CraigT

It’s been a busy week.

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. Over the last week I’ve used this to hook up proper border emulation:

http://speccyds.wordpress.com/files/...keggborder.jpg

The first screenshot is the result of a BASIC Save command and demonstrates the border quite well. The second shot demonstrates the scaling problems that are associated with displaying the borders on such a small screen.

Luckily, the DS hardware makes screen scaling very simple. Therefore, I will probably add three border settings - None (default), Thin and Full. The thin border should keep the distortion down to a minimum.

A few other things have changed, including:

- The Z80 loader has been fixed. All 48k-based .Z80 files should now be accepted without causing the Spectrum to reset

- Simulated the resistor connection between the EAR and MIC ports on the spectrum. Sound is now produced when using the BASIC save command etc

- Fixed the flags on the DAA instruction to fix Head Over Heals. However, the sound still cuts out in some rooms

- Fixed the crash in Starquake (yay!). It was caused by a silly bug in the HALT instruction

Next up is DLDI support…

I’ve also added a Donate tab at the top of the blog. Developing SpeccyDS takes up a large amount of my free time. If you are feeling generous, please show your appreciation by donating a few pounds towards the project. Any amount is gratefully received! Thank you :)