A Scala Commodore 64, 128, VIC20 and CBM 610/620/710/720 cycle-exact emulator

Kernal64 ver 1.8.6b1 (Oct 07th, 2025)

▶️<a href="#wn-latest">Go to latest release</a>

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Commodore 64

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Main features

• [x] 6510 CPU cycle-exact
• [x] True drive emulation of 1541, 1571, 1581. Supported disk images:
  • D64
  • D71
  • D81
  • G64
  • G71
• [x] Local filesystem mounted as a drive
• [x] Tape emulation. Supported tape images:
  • TAP
  • T64
• [x] Keyboard editor
• [x] Joystick emulation
  • Keyboard
  • USB joystick
• [x] SID 6581/8580
• [x] Dual SID emulation
• [x] Light pen and 1351 mouse emulation
• [x] MPS803 printer emulation. Print preview panel.
• [x] VIC II
  • PAL / NTSC model
  • Palette
  • Rendering options and effects
  • Full screen
• [x] Cartridges
  • WiC64
  • BeamReacer
  • REU
  • GEORAM
  • SwiftLink
  • DigiMAX
  • ActionReplay
  • KCS
  • FinalCartridge I
  • FinalCartridge III
  • Simon's Basic
  • Comal 80
  • Magic Desk
  • Dinamic
  • Game System
  • Warp Speed
  • Easy Flash
  • Ocean
  • Fun Play
  • Super Games
  • Epyx Fastloader
  • Super snapshot 5
  • GMOD2
  • GMOD3
  • Zaxxon
  • Mach 5
  • Page Fox
  • CP/M
  • Super Explode
  • RAM Cart
  • Isepic
• [x] RS-232 and Internet connection
• [x] Flyer internet modem
• [x] State saving
• [x] GIF Recorder
• [x] Assembler / Debugger
• [x] Game portals

Commodore 128

<img src="https://github.com/abbruzze/kernal64/blob/master/images/commodore128_vdc.jpg" alt="Commodore 128 VDC"/><br>

Main features

• [x] ▶️<a href="#c64-features">See C64's features</a>
• [x] Z80 instruction-exact emulation
• [x] MMU status panel
• [x] VDC standard and interlaced modes
• [x] 2Mhz mode
• [x] Internal and external function roms
• [x] 128 Cartridges:
  • Megabit
  • Magic Desk 128
  • Generic 128
  • Magic Desk 16K

VIC 20

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Main features

• [x] 6502 CPU cycle-exact
• [x] Memory configuration panel
• [x] True drive emulation of 1541, 1571, 1581. Supported disk images:
  • D64
  • D71
  • D81
  • G64
  • G71
• [x] Local filesystem mounted as a drive
• [x] Tape emulation. Supported tape images:
  • TAP
  • T64
• [x] Keyboard editor
• [x] Joystick emulation
  • Keyboard
  • USB joystick
• [x] Light pen and 1351 mouse emulation
• [x] MPS803 printer emulation. Print preview panel.
• [x] VIC
  • PAL / NTSC model
  • Palette
  • Rendering options and effects
  • Full screen
  • NTSC interlaced mode
• [x] Cartridges
  • Final Expansion 3
  • Geo RAM
  • Ultimem
  • VIC 1112 IEEE488
• [x] RS-232 and Internet connection
• [x] Flyer internet modem
• [x] State saving
• [x] GIF Recorder
• [x] Assembler / Debugger
• [x] Game portals

SuperCPU

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Main features

• [x] ▶️<a href="#c64-features">See C64's features</a>
• [x] WD65816 instruction-exact emulation
• [x] SIMM memory: up to 16M
• [x] Emulation of 1Mhz mode during I/O access partially supported
• [x] Shipped with VICE's SCPU rom. CMD's rom 2.04 also supported
• [x] Leds panel: native (65816 in native mode), 20Mhz (turbo mode on), clickable JIFFYDOS (jiffy dos enabled), clickable SPEED (master speed selector), SIMM usage (% of SIMM usage)

CBM II

Main features

• [x] 6509 CPU cycle-exact
• [x] Not true drive emulation of IEEE488 8050. Supported disk images:
  • D80
• [x] Models:
  • 610 PAL/NTSC
  • 620 PAL/NTSC
  • 710 NTSC
  • 720 NTSC
• [x] MPS803 printer emulation. Print preview panel.
• [x] ACIA and Internet connection
• [x] State saving
• [x] GIF Recorder
• [x] Assembler / Debugger

Installation

Go to https://github.com/abbruzze/kernal64/releases/latest and download and unzip on your computer the latest version. Be sure to have a jre (11 or above) in the path and launch:

• On Windows: k64.bat, kscpu64.bat, k128.bat, vic20.bat or cbm2.bat. If you want the shell support (for --help command line, for example) you should use --shell as first option.
• On Linux: k64.sh, kscpu64.sh, k128.sh, vic20.sh or cbm2.sh.

The scripts start java with the -server option for performance reason. It could happen that your Java installation does not support the server option. In this case edit the script and remove the -server option.

If you want to load a 16M REU modify the memory settings inside the start scripts: for example, you could set -Xmx128M.

Wiki

Wiki pages are available here: https://github.com/abbruzze/kernal64/wiki

What's new history

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What's new 1.8.6b1 (Oct 07th 2025)

• Commodore 128
  • Added support for Magic Desk 16K cartridge: now SNK vs CAPCOM for C64/C128 can be run in 128 mode
  • Fixed loading of zex128 tests in testbench

What's new 1.8.5b1 (Jul 16th 2024)

• Commodore 64
  • Fixed REU read/write from/to 0/1 locations: must read/write ram
• Games
  • Fixed loading of GameBase games (they changed urls): download of PRG/D64 seems to be no longer available

What's new 1.8.4b1 (Sep 3rd 2023)

• Fixed joystick emulation with keyboard: fast direction changing (left<->right or up<->down) didn't work properly.
• Added fast save/load states.

What's new 1.8.3b1 (July 20th 2023)

• Fixed bug introduced in previous releases that affects drives (specifically 1541) when user change a floppy. Some demos stop to recognize the change of floppy when requested.

What's new 1.8.2b2 (Apr 21th 2023)

• General
  • New keyboard layout handling: now it is possible to use a more natural layout assigning different host keys to the same emulated key. The layout configuration is stored inside a configuration file, depending on the emulated machine. Each configuration file can contain different layout for different operating system. See Wiki for details. <br>
  • New virtual keyboard and keyboard editor: it's possible to enter key using a virtual keyboard. It's possible to edit the keyboard configuration or create a new one from scratch.
  • New look and feel Flatlaf (thanks to https://www.formdev.com/flatlaf/)
  • Added support for palette configuration loading from file (vpl) for both VIC (I,II) and VDC
  • Fixed disk issues when user change disk
• C128
  • Improvements for 2Mhz emulation
  • Improved MMU (https://sourceforge.net/p/vice-emu/bugs/1835/?page=1)
  • Minimal modifications to D030 registry: still partially supported
  • Added ASCII/DIN handling for multilingual char rom set. Fixed 128/64 char rom reloading
• C64/C128
  • Added Super Explode cartridge
  • Added RAM Cart cartridge
  • Added Isepic cartridge
• VIC20
  • Added support for WiC64
• CBMII
  • Fixed 8050 DOS emulation

What's new 1.8.1b1 (Feb 2nd 2023)

• Added support for Magnum Light Phaser light gun. Duck Hunt can be played now (https://csdb.dk/release/?id=226342)
• Fixed audio state saving.
• New initialization memory pattern for all machines.
• Added video & audio support for freespin demo (http://www.quiss.org/freespin/). How to lunch the demo:
  1. Run the demo
  2. When it is asked to open/close the driver's lever, re-insert the same demo disk
  3. Under Settings -> I/O check "freespin cable enabled"
  4. When the demo finishes uncheck the "freespin cable enabled"

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What's new 1.8.0b2 (Dic 1st 2022)

• New emulators: VIC20 and CBM-II (610/620/710/720)
• New Debugger
• USB Joystick: on (my) Windows 10 laptop jinput library seems to hang sometimes during initialization, freezing the whole emulator. Added a separate thread to check usb joystick availability.
• C64
  • Dual SID fixed: some release ago was broken

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VIC20's main features

• True drive emulation of 1541, 1571, 1581
• Tape emulation
• VIC
  • PAL / NTSC model
  • Palette
  • Rendering options and effects
  • Full screen
  • NTSC interlaced mode
• Cartridges
  • Final Expansion 3
  • Geo RAM
  • Ultimem
  • VIC 1112 IEEE488
• RS-232 and Internet connection
• MPS803 printer emulation. Print preview panel
• Game portal (Pouet)

<br>

CBM-II's main features

• 6509 CPU cycle-exact
• Not true drive emulation of IEEE488 8050. Supported disk images:
  • D80
• Models:
  • 610 PAL/NTSC
  • 620 PAL/NTSC
  • 710 NTSC
  • 720 NTSC
• MPS803 printer emulation. Print preview panel
• ACIA and Internet connection

<br>

What's new 1.7.4b1 (Jul 29th 2022)

• General
  • Added support for G71 disk format
  • Fixed state saving support: broken on last Wic64 release
  • Adjusted LAST_SECTOR_GAP in gcr handling to a larger value: demo E2IRA now runs fine (except for a part into disk B that is not visible; border must be turned off !!)
• C128
  • Added support for MagicDesk128 cart (https://github.com/RetroNynjah/Magic-Desk-128). It can be possible to run VolleyForTwo game with cartridge (https://kollektivet.n