The memory on the old BOSS machines is on the LSI-11 board. There were 3 versions. There was a 4 LSI (large scale integration) ICs on it. Used on the BOSS 3 and 4. The 5 LSI version was used on the BOSS 5 and 6. There was a half size version used on the BTC-1 AKA BOSS7. All these were made by DEC (digital equipment corporation) and were called the KD-11F and KD-11L for the 5 LSI. I do not remember their designatiom on the 1/2 size. I will look up some data I have on this board but a good EE would have to figure out how to expand the memory assuming it can be. then are these antique memory ICs still available. Two examples. I had an old ATARI 400 to which I soldered a piggy back board that expanded my RAM to 8K. It also had a modem and floppy attached to it but back then (1980) there were only BBS (bulletin board service) on line. My TRS80 Model 100 came with 8 K of RAM available to me. I purchsed ICs that expanded that to the full 32K. This is toward the tail end of the stepping motor BOSS sale span so I believe that these mother boards will suffer the same limitations. In other words, how far will that get you with a large program? Is if even worth trying to figure out. A complete replacement of the logic section is the only viable alternative. It is also getting to the point that it is not cost effective to buy replacement boards for these machines. I am not familiar with the BTR devices now available, but if I had a paid for BOSS machine it would be tempting to try. Especially since some claim DNC capability. It is a way around the limited memory.
George  |