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Perdita

Description and features

Perdita is a Durango Emulator that can run any ROM created for Durango. Perdita is based on the 65C02 instruction set and the Durango-X architecture, but currently does not support the Rockwell R65C02 extensions. However, the WDC WAI and STP opcodes are emulated, the former as a breakpoint.

Perdita Emulator

Durango Emulator

With Perdita you can test your developments and use the internal development tools, like memory dump or gamepad emulation. Emulation is complete and, on a reasonably powered computer, cycle-accurate. The only current caveats are:

  • Sound is emulated, but some distortion may be heard.
  • Real-time video mode switching won't display properly on the emulated screen.

Using Perdita

Installation

Perdita uses the SDL2 framework to display the screen contents, so you need to install it on your system (Linux only):

apt install sdl2-dev

You can find the source code of Perdita in the following Repository:

https://github.com/durangoretro/Perdita

You can use Makefile to generate the perdita executable.

make

Generate Perdita for Windows

If you want to build Perdita for windows, you need to use mingw32 to generate the .exe file, with the following make goal: 

make perdita.zip # Only for generating a Windows executable

Generate Perdita using Docker

You can use the following DockerFile to generate a container with Perdita: https://github.com/zerasul/dockerretro/blob/master/sdl/Dockerfile.

Use

To run Perdita, you can use the following instructions:

./perdita [options] <path to romfile>

The available options are:

  • -a: load ROM at supplied address, for example 0x8000.
  • -f: fast mode.
  • -s: safe mode (will stop on warnings and BRK).
  • -p: start in STEP mode.
  • -l: enable error LED(s).
  • -k: keep GUI open after program end.
  • -h: headless -- no graphics!
  • -v: verbose (warnings/interrupts/jumps/events/all).
  • -r: do NOT randomize memory at startup.
  • -g: emulate controllers (Gamepads); you can use usb gamepads with durango emulator.
  • -m: do NOT emulate Minstrel-type keyboard.

Also, you can execute some commands using functions keys:

  • F1: Stop emulation and quit.
  • F2: NMI Button (Non-Maskable Interrupt).
  • F3: IRQ (Interrupt ReQuest).
  • F4: Reset.
  • F5: Pause and display status.
  • F6: Dump memory (and register) contents.
  • F7: Single-Step execution (while paused).
  • F8: Resume normal execution (from pause).
  • F9: Load dump file (dump.bin).
  • F10: Load keystrokes file (keystrokes.txt), emulating each keystroke every 25 interrupts (1/10 second), or 50 interrupts in case of the ENTER key.

Virtual Serial Port (VSP)

As a valuable debugging tool, a Virtual Serial Port is provided. It allows communication with the host environment thru a predefined I/O device occupying two addresses: $DF93 for data exchange and $DF94 for configuration.

Keyboard emulation

Perdita includes two kind of keyboards: an "intelligent" PASK-like device (ASCII character received at $DF9A) and the Minstrel-like 40-key keyboard provided as standard (at $DF9B). The latter can be disabled with the -m option for debugging purposes.

Gamepad emulation

Two NES-type gamepads are emulated into the standard I/O addresses $DF9C and $DF9D, using the standard protocol. If no physical gamepads are available, they can be emulated by host keystrokes via the -g option.

MAME

MAME is a popular arcade/retro-system emulator. Currently, there is no support for Durango-X in MAME, but contributions are welcome!