Friday, June 14, 2013

Vectrex Homebrew Cartridges

Last year I got myself the famous Vectrex console.For those who don't know it: The Vectrex made by MB is the only homeconsole with a real vector graphics display as It was used in early arcade games like Asteroids, Lunar Lander and Tempest. Because of this design it's impossible to use a standard television with this system as these devices are only able to rasterize a picture line by line. Vector systems on the other hand directly control the beam of the cathode ray tube to draw dots and lines.
This is why the vectrex has a built-in monitor ... which can be destroyed by software.

Here is a picture of my unit.

Here is another picture of my units tube.

This "hole" is not photoshopped. The small dot indicates that the fluorescent layer was burned away at that point. Talking about "Killer Pokes" here. It's like a damaged pixel on a TFT monitor. It's always there and you have to look at it. Anyway....

According to Wikipedia the Vectrex has only 20 official games released in europe which is sadly not a lot. To overcome this problem and because programming games with vector graphics is awesome as hell this platform got a great homebrow community. A lot of these games are released on custom manufactored cartridges and also a few with integrated non-volatile memory for highscore savings (which is not common on this device). But not all of them.

As this device is not that popular not a ton of "flash cartridges" exist that let you burn your own games onto. A very good example is the VecFlash and the VecMulti made by Richard Hutchinson. Sadly both are sold out at least since 2012-08. I tried to contact him at that point but the status hasn't changed since then. Both cards were very sophisticated. In special the VecMulti which offers to load games from MicroSD and has a debugging port for homebrew development.
Another alternative would be to destroy an existing card by replacing the rom by an eprom and then use this one. Also you can use extra adress lines to select different games. This is how a lot of "MultiCarts" are designed.

A lot of time passed since then and I thought myself it would be funny to make a EPROM based solution myself. It will not be as great as the "VecMulti" but it will suit most of the needs. I finished a long ago started design today and ordered the PCB. So stay tuned.

The only downside with my design is the lack of backup memory which is used at least by the games Thrust, Protector and Y.A.S.I which are one of my favourites. I couldn't find schematics which show how that works and where the needed EEPROM is applied but the design is made flexible so it may be possible to add that later.


  1. You may want to contact Richard H over at for some assistance on the memory backup. He is very helpful.

    1. I don't think so. I asked him for schematics of the VecMulti as I wanted to know how he has solved the problem of communication between the microcontroller and the sram as the vectrex also has access to it.
      Maybe I wanted to much. Besides I've evaluated the sourcecode of "Thrust" which is opensource. This game uses a 1-Wire EEPROM for savings. I've included it in the design a few hours after writing this blogentry.
      I hope that Y.A.S.I and Protector use also this solution.

      But thank you. You are right. I need to ask different people. And maybe after these months Richard H. is more cooperative. :-)

    2. hmm that's strange, just replied but it didn't gey published. The 1-Wire EEPROM for YASI is on I/O line (PB6) of the Vectrex cartrdige slot. I believe this code is used by other homebrewers too.
      For more info you can see the source code made by Alex Hubert the author on his website at

    3. Wow. Thanks. Blogger marked your post as spam. I fail to see why.
      I contacted Richard again and he responded very fast and was quite helpful. He said the same as you do here and has given me a few advices about electrical things I should care about. Still he hasn't said anything about the future of the VecMulti.

      The source code of Alex Hubert is actually the one used by "Thrust" as It turned out.

  2. You might also contact Johannes at

  3. You can find more info about the 1 wire EERPOM from the freely available source code from Alex Herbert - which has been unofficialy adopted by other homebrewers. Comms with the EEPROM is through I/O line (PB6) on the Vectrex cartridge slot. The source code is at

  4. Johannes at does not respond to emails. The vectrex world have been waiting for him to return and start selling his products again - but its been a few years now.

  5. The VecMulti is still available from Richard H uncased. He will sell you the circuit board without case; it comes with the SD card and free shipping for the same price as the cased VecMulti. You can PM him on the AtariAge forum for ordering info. I just bought one from him in Nov. 2013, and it's very easy to use and house in a standard Vectrex cartridge. I used an old Heads Up Action Soccer cart.

    1. Thanks a lot for this comment. This is something he really needs to say on his webpage. Problem is that I'm rather satisfied with my solution. I have to agree that homebrew development is frustrating with this thing as programming an oldschool eprom takes some time. And emulators are not as good as I thought. Even ParaJVE differs a lot when it comes to the drift and brightness simulation.