Table of Contents
Most of these projects are 8-bit stuff for the Commodore VIC-20, Arcade games from the 80's or my own reincarnation of a 8-bit machine based on the 65C816.
All done with a specific idea or test in mind. Beeing testing GreenPAK, New circuits for USB Type-C PD Sink or FPGA implementation of USB 3.0.
FATVIC
My FATVIC is a replacement for the VIC chip with VGA output. It also has full memory on BLK0 and some other enhancements.
The thing I wanted to solve here was no drilling in the case, any changes reversible, and no wires hanging out through the casing, but VGA with audio. I solved this by desoldering the DIN connector replacing it with a plastic dummy that holds a small rigid-FPC up side down having a 8 pin miniDIN with VGA and audio. Fitting nicely in the large hole of the normal video DIN. The FPC connected to the FATVIC. If you want.
Otherwise it emulates the ordinary video through the ordinary DIN. Well is supposed to.
To have BLK0 full you also need to socket one of the decoder logic chips. Namely the 74LS138 for BLK0. This is also reversible though. The small board that sits in the socket detect if the FATVIC is missing and reverts to ordinary function. When enabled it also pulls the RAM1/2/3 on the cartridge port high to disable any 3k in a cartridge from being selected.
GCart Family
I have had a numerous variants on the GCart. It started in 2011, and I do not remember where I got the GCART naming from.
There has been two main families. The GCart, GCart BX and GCart MX. These have all memory often banked and in the range of MByte, WiFi, and often an IEC bus. SD Card and/or embedded massive FLASH.
The GCart Jr, is focused on low cost, but usually have quite a descent feature set.
Lastly we have GCart DCNT (Dirt Cheap No Thrills). This is typically only memory with no banking what so ever.
GCart Jr III
This is the latest of the Jr type.
- RAM at the lower 3k, BLK1, BLK2 and BLK3, as well as BLK5.
- It also have 16MByte of FLASH for applications that are cartridges or single loaded programs.
- Optionally it has an RTC, Display, SD Card, and a general MIDI synthesizer.
GCart DCNT
The Dirt Cheap No Thrills memory expansion. Sub 5 USD in BoM cost.
- Memory in BLK1, BLK2, BLK3, BLK5, The lower 3k as well as IO2 and IO3.
- Simple UI with 4 LEDs and one button, which also is a RESET button.
GCart MX
The Max memory expansion. The inverse of DCNT. Spare no expense style ...
- FPGA based. This is run on a 12k LUT FPGA from Lattice.
- Memory in BLK1, BLK2, BLK3, BLK5, The lower 3k as well as IO2 and IO3. All mapped into 16Mbyte HyperRAM with twin controllers.
- Builtin Meatloaf on a RISC-V soft MCU with a uBlox WiFi/Bluetooth. Both IEC attachment as well as a warp speed loader for 250kbps speeds.
- 16MByte internal FLASH and micro SD card for even more. Both connected to Meatloaf.
- MIDI IN/OUT.
- General MIDI synthesizer.
- UI is a segmented custom LCD display with the same illuminated reset/configuration switch as all the other.
With an optional internal encoder, instead of the ordinary UC5, other features can be unlocked. The internal encoder replaces UC5 and also encodes A14 and A15 on to the NC - Not Connected pin 20 in the cartridge port for a few other possibilities.
- HDMI output and emulation of the VIC chip, with many of the feature from FATVIC.
- USB Gamepad that handles both analog and digital controllers.
- Possibility for different Kernals and BASICS.
This is however the most ambiguous expansion I have done. Electronics is easy peacy, but all software will be quite a ride.
VIC NX
VIC NX is my incarnation of the classic VIC 20. The mail goal is to create a fully compatible VIC 20 clone, but with some extras.
It fit in the original breadbin box. The only things that will hint on differences is two things is the top-led and the side-panel.
It sports fully expanded memory, and som more, 512k FLASH for Kernal and BASIC as well as a integrated Meatloaf.
VIC PSU
VIC PSU is a very small USB Type-C to VIC 20 / C64 DIN adapter. It turns any Type-C PD capable power supply into a PSU for a Commodore VIC 20 or C64 with DIN connector.
First version was only for the VIC20. That Commodore computer can live happy with 9V DC in the 9V AC pins of the DIN connector, IF you sacryfice the 9V AC for the user port that some accessories need. Namely EPROM burner and modems. Accessories that use the 9V AC to step up to different voltages.
The C64 is different it needs the AC voltrage both to keep TOD (Time of Day running), but more importanly it needs it for various internal voltages for SID and other components.
The original PSU also has a isolated 9V AC wich floats in regard to other references, i.e GND.
Willy Wonka
This is actually some of my oldest projects. They have been dormant for quite some time, but I needed to quickly get one om my old VIC 20 with bad RAMs up and running for testing purposes, so I cleaned this up and it works pretty well.
It is a series of internal expansions where the goal has been to make it as easy as possible to install. Given that you already have certain amount of chips in sockets. Otherwise that needs to be done. Most of mine have, and have had since I bought them second hand. I have one that has everything soldered, except VIC chip.
Willy Wonka CR
This is a small board for the CR main boards that replaces the 1k x 4 SRAM chips as well as the Color SRAM. It contains 8k SRAM for BLK0 and all is accessable by the VIC chip. This solved the biggest design flaw in my opinion.
Willy Wonka CR Adapter
Willy Wonka CR Adapter is a small board that replaces the 74LS138 that is used for SRAM selection. From here we get a few vital signals needed. We also disables all internal memory and the 3k expansion for the cartridge port. A small FFC connects the Willy Wonka CR with the Adapter.
Willy Wonka CPU
Willy Wonka CPU is a similair board that attaches in the place of the 6502 CPU (can also handle 65C02) and UC5 (another 74LS138 that handles the 8k BLK selection).
This board gives full memory expansion at BLK1, 2, 3 and 5. It also has 512k FLASH with software selected banks for BLK6 and BLK7.