Originally Posted by
yenots
I spent the better part of a week trying to get a Protomat 91s to play nicely with Boardmaster. I tried every single recommended cable configuration from this forum and others. Some worked better than others, but the buffer overrun kept cropping up, sometimes with an out of date EPROM error.
All of these experiments were done with a Windows XP machine (Thinkpad and a docking station that has a native COM port), and Boardmaster 5.0. Finally I decided to downgrade to Boardmaster 3.0, as it seemed to have all the functionality that the 91s requires.
BINGO! Runs like a champ with Boardmaster 3.0, not a single error in over an hour of runtime. Plus, this is with a GENERIC null modem cable. NO jumpers, nothing extra.
Note that I did not try running it from a USB to RS232 adapter--that confguration may have other issues.
This 91s had been sitting unused for over 15 years, and initially refused to power up. This was tracked down to a shorted electrolytic cap on the output of the 5V supply. The depth adjuster needed a bit of cleaning and lubrication, too. Beyond that, runs like a champ.