Skipping 0.1.4 - hello 0.2.0!

[dbalsom]

There's enough 'new stuff' in the development branch that I figured it warranted a bit more of a version bump for the next release. So I am now working towards 0.2.0.

I apologize for the long delay without any new release. If you've been following my blog, however, you'll see that I have not been napping - I've been doing extensive research into the 8088's last few secrets, developed new hardware bus sniffing and debugging methods to tackle current and future issues. Much of MartyPC's CPU core has been rewritten to squeeze out even more accuracy, completely rewriting BIU state logic and improving interrupt timings. The CGA has gotten some love too; fixing a few remaining CRTC issues.

There are still a few goals I have before 0.2.0 can happen:

• New ROM definition system. (DONE)

  • The old system with hardcoded hashes in source is inflexible and difficult to maintain. I would like to move rom definitions to external TOML files. MartyPC will scan the ROM directory for these definition files and load them; this allows ROM developers or tinkerers to make their own rom definitions easily without needing the old 'rom_override' config option. ROM sets can be given a nickname and then referred to via the main config or chosen via command line option.

• Machine definition system (First pass - configuration system - DONE)

  • 0.2.0 will probably only have the basic framework of this at first, but we will want a way to configure profiles for different machine configurations.
  • Allow for configuration of RAM and DIP settings at bare minimum.
  • Eventually, I would like this system to be flexible enough that SBC makers can define their target hardware by selecting the right components and base IO and memory locations.

• More Keyboard mapping files and UI support

  • 0.2.0 has a completely rewritten keyboard system including keycode abstraction, Model F keyboard emulation, scancode mapping and scancode macro support. Currently I have implemented a mapping file for Italian keyboards; we need to create mapping files for additional international layouts. I may need some help with this!
  • Add UI option to disable mappings & macros if they are causing issues
  • I was developing graphics and UI designs for an on screen keyboard, but this may not make it into 0.2.0

• More display scaling options

  • This is probably the number one most requested feature. We should be able to scale the screen to select from the default integer scaling method, proportionally scale to fill the screen, or stretch to fill the screen, ignoring aspect ratio. (DONE)
  • Full screen support. Winit supports this in theory, we just need to implement it. (DONE)

• CGA improvements

  • CRTC improvements
    • I've been working on fixing the last CRTC issues related to vsync timings. This should be completed soon. (DONE)
    • Selectable aperture support - move the 'frame debug' feature to the UI and allow it to always be toggled. Keep the current aperture as a 'full overscan' option, and add a more heavily cropped 'IBM 5153' display aperture. Adjust screenshot logic to match selected display aperture. (DONE)
  • The CGA can clock itself by cycle or character. I would like to add clocking by scanline as well - this will be the default clocking interval until a register access happens, where we will drop down to cycle-accuracy, then back up to character accuracy for the next scanline, eventually flipping back to scanline-accuracy on the next scanline (until another register access happens!)

I definitely want this out by the end of the year - I need to beat the Area 5150 crew before they release their final version (which may not work without all my fixes!)