REU-focused cartridge firmware for the Commodore 64/128, based on Kung Fu Flash 2.
This fork is focused on making the cartridge behave as a dedicated REU cartridge by default:
- REU support is enabled by default and kept active for user programs
- Boot no longer depends on an inserted FAT-formatted microSD card
- When no SD card is present, the launcher shows
REU Activated. Jumping to BASICand jumps to BASIC after 5 seconds
Kung Fu Flash 2 can emulate different cartridge types, load PRG files and use D64 disk images. Just place your desired CRT, PRG or D64 files on a FAT formatted microSD card and use the built-in launcher to execute them.
There are three buttons on the cartridge; a reset button, a menu button for starting the launcher, and a special button that is used by the freezer cartridges.
The form factor is similar to Kung Fu Flash and it should be possible to use the same cartridge cases. It could be the Stumpy Cartridge Case from TFW8b or the 3D printed cartridge case designed by bigby, see here.
The gerber files and BOM can be found here.
The following cartridge types are currently supported:
- Generic cartridge (8k, 16k, Ultimax)
- Action Replay v4.x/v5/v6
- KCS Power Cartridge
- Final Cartridge III(+)
- Simons' BASIC
- Fun Play, Power Play
- Super Games
- Ocean type 1
- Epyx Fastload
- C64 Game System, System 3
- WarpSpeed
- Dinamic
- Zaxxon, Super Zaxxon
- Magic Desk, Domark, HES Australia
- Super Snapshot v5
- Comal-80
- Ross
- EasyFlash
- Prophet64
- Freeze Frame
- Freeze Machine
- MACH 5
- Pagefox
- RGCD, Hucky
- Drean
- C128 Generic cartridge (external function ROM)
- WarpSpeed 128
The following file types are currently supported:
- Cartridge (CRT)
- C64/C128 generic cartridge (ROM, BIN)
- Disk image (D64, D71, D81)
- Tape image (T64)
- Program (PRG, P00)
- Firmware update (UPD)
- Text document (TXT, NFO, 1ST)
KFREU emulates a 1 Mb REU (RAM Expansion Unit) simultaneously with disk drive emulation. REU is always enabled in this fork and available when:
- A program is executed using the default option (RETURN)
- A disk image or directory is mounted using "Mount" in the file options menu (SHIFT+RETURN)
- BASIC is started via F6 (C128) or F7 (C64) in the launcher
The REU is intended to remain active for normal user/program operation in this fork.
The USB port allows programs or disk images to be transferred from/to a PC using the EasyFlash 3 USB protocol. The USB port is active when:
- The Kung Fu Flash 2 launcher is running
- A program is started using "Load" in the file options menu (SHIFT+RETURN)
- BASIC is started via F7 in the launcher (USB behavior may differ from upstream due to always-on REU)
Kung Fu Flash 2 shows up as a standard serial port when connected to a PC not requiring any custom drivers to be installed. This means, however, that the EasyFlash 3 program on the PC side must be modified to support Kung Fu Flash.
The repository of the original Kung Fu Flash contains a modified version of EasyFlash 3 USB Utilities and EasyFlash 3 BBS which will also work with the Kung Fu Flash 2.
Just place the KungFuFlash_v2.xx.upd file on the SD card and select the file in the launcher to initiate the firmware update. The newest firmware can be found here.
For initial firmware installation, see here.
Kung Fu Flash 2 is a so called Software Defined Cartridge where a fast microcontroller emulates cartridge hardware in software. This makes it extremely flexible, allowing different cartridge types to be supported at a relative low cost.
However, it can be challenging to get the C64 bus timing correct in software and in some places the timing is very close to the limit. Even though Kung Fu Flash 2 has been tested on different models of the Commodore 64, there is a chance that it doesn't work correctly on your specific model, or requires phi2 offset adjustment. Use it at your own risk!
Kung Fu Flash 2 will work with the PAL and NTSC version of the Commodore 64 or Commodore 128.
Disk drive emulation is using kernal vectors and will not work with fast loaders or software that uses direct hardware access which a lot of games does. Currently REL files are not supported and only a subset of the Commodore DOS commands are supported.
KFREU is based on Kung Fu Flash 2, which was based on or uses other open source projects:
- Kung Fu Flash
- EasyFlash 3 by Thomas Giesel
- Draco Browser by Sascha Bader
- fatfs-stm32 by Aurelio Colosimo
- FatFs by ChaN
- libusb_stm32 by Dmitry Filimonchuk
- OpenC64Cart by Giorgioggì
- Disk2easyflash by ALeX Kazik
and a few others. Please check the individual files for their license.