VIC-20 for MIST Board

Features:

• Based on The Replay Board code
• 3k RAM Expansion at $0400
• 8k/16k/24k RAM packs from $2000
• Read-only or writeable CART memory at $a000
• Joystick support
• PAL/NTSC Display (with optional scandoubler for VGA monitors and YPbPr component output)
• PRG/CART loading
• 1541 Disk Drive support
• Mega-Cart support

CART/PRG loading

CRT and PRG files usually has the load address in the first two bytes. If a particular file doesn't contain this address, you can load it to the default $a000 via choosing 'CRT with load address: No' option in the OSD menu. Loading a cart to the $a000 location will auto-reset the core, so it'll start automatically. If you have a multi-part cartridge, then first load the part which doesn't load to $a000. Also don't forget to enable 8k ROM option for cartrdiges!

RAM expansions

The core supports from the orginal unexpanded (5k RAM) machine to a fully extended one (total of 40k RAM). Unfortunately not all games supports all expansion modes, so you have to figure out what a particular game requires.

RAM map:

• 3k Extension: $0400
• 8k+ Extensions: $2000, $4000, $6000
• 8k ROM/RAM: $a000

If the Mega-Cart is used, then managing the RAM expansion configuration is done in its menu.

ROM file:

A VIC20.ROM file is mandatory at the root of the SD Card. The file format is: 1541 (16k) + Kernal PAL (8k) + Kernal NTSC (8k) + Basic (8k) + Char (4k).

Hotkeys:

• F9 - Tape start/stop
• F10 - Reset
• RShift + F10 - Reset with cart unload
• F11 - Restore

Download pre-built binaries:

https://github.com/mist-devel/mist-binaries/tree/master/cores/vic20

Source code:

https://github.com/gyurco/VIC20_MiST