All – I’ve done a quite a bit of work with my Gazelle, and doing some work on 86DOS and its comparison to PC DOS 1.0 (at the code level, a very high correlation). Partially related to that is a program called “20HAL” which was a code uploader Microsoft used in the late stages to get code to IBM in Boca Raton, FL. I did a little write-up on it here (http://www.classiccmp.org/cini/hal.htm) There are some holes in the analysis – I think it’s pretty close, though -- but I’d really like to get some more details on it. Unfortunately, it’s 40-year-old code at this point and how many people remember how they used a file transfer utility that long ago. Anyway, enjoy the read. If anyone sees any corrections that need to be made, let me know. Rich -- Rich Cini http://www.classiccmp.org/cini http://www.classiccmp.org/altair32