UMI 3K VIC Memory Expansion
Harvey B. Herman
This small circuit board is designed to plug into the 44 contact female edge connector inside the VIC. It adds 3K of RAM memory to the 5K normally present. When the VIC is powered up, the bytes free message should now total 6655 instead of 3583. This means that programs loaded from tape can be almost twice as long as before without running out of memory. The board also has two empty ROM sockets which allow up to 16K of programs on chips to reside permanently in memory. These programs do not disappear when power is turned off or lost. Initial startup with ROM-based software is much more convenient compared with a long program loading from tape. Many ROM games and other interesting ROM programs will be marketed by UMI and other companies. This board will allow you to use them without additional expense.
The circuit board is easily installed. The VIC case does not even have to be opened as the board fits through the opening in the rear. If you read and follow the quite explicit directions, I predict you won't have any difficulty.
It's Solidly Constructed
I have several positive comments. The board looks solidly constructed and seems to be well thought out. Each ROM can be placed in one of two areas of memory and three ROM sizes can be accommodated. The instructions even give technical hints to advanced hobbyists who intend to program their own ROMs. The price is competitive with similar boards I have seen advertised, but have not yet examined critically.
I have two minor negative comments. Contact fingers on the board are not gold plated so corrosion could be a problem under certain conditions. This will probably not be a concern in typical household use, however. The board sticks out a little from the back of the VIC and is unprotected. Users will have to take care that it does not get knocked about. Again, I do not see this as a serious problem.
As you may have inferred, I am quite happy with this memory expansion. I felt somewhat limited by the small amount of available RAM in the original VIC. Now I can run more ambitious programs. I am also looking forward to installing the better ROM-based programs when they become available.
United Microware Industries
3431 H Pomona Blvd.
Pomona, CA 91768