I worked with Dave from 1965 until he left Michigan about 5 or 6 years later. This was before the Internet, before NTP, before time.
In 1966 I was laying the foundation for what would become MTS and Dave was designing and building the Data Concentrator to connect the outside world to it. The Data Concentrator was almost certainly the first non-IBM device to be connected to an IBM channel, just after the "consent decree" that forced them to publish the specs. These specs were only approximately correct and Dave and I spent many hours at the consoles on the Data Concentrator and the Model 50 respectively debugging the interface. I would key in a small channel program and run it. The model 50 would go into a microcode loop while Dave scoped the interface. I would do a system reset on the 50 and he would patch the code in the PDP-8 and we would try again. After many iterations of this it finally worked.
Dave was very low vision even then. It's amazing he did as much as he did without the modern low vision aids. We used to joke that he would wire his nose into the back panel of the concentrator since he had to get so close to see the pins. In recent years I, too, have become low vision and Dave is my role model in this regard too. He had an unusual form of childhood glaucoma. For years the doctors kept one step ahead of it and he kept some vision, but when I EMailed him recently I learned that he had become completely blind.
For a few months Dave and I were the only consultants on the help desk at the Computing Center for one or two shifts a week. We had a lot of fun, but it must have been an odd experience for the students who came in for help with their MAD programs.
In spite of his vision problems, Dave was an avid photographer. In fact he took the picture of me at the 360/67 console that is floating around the Internet. Dave and I both went to Israel in 1969 with Bernie Galler's seminar series and spent a lot of time wandering around in our free time. Dave used to have photos from that trip up on his web site.
He was one of the most interesting and smartest people I have ever known. He will be missed by all who knew him.
In 1966 I was laying the foundation for what would become MTS and Dave was designing and building the Data Concentrator to connect the outside world to it. The Data Concentrator was almost certainly the first non-IBM device to be connected to an IBM channel, just after the "consent decree" that forced them to publish the specs. These specs were only approximately correct and Dave and I spent many hours at the consoles on the Data Concentrator and the Model 50 respectively debugging the interface. I would key in a small channel program and run it. The model 50 would go into a microcode loop while Dave scoped the interface. I would do a system reset on the 50 and he would patch the code in the PDP-8 and we would try again. After many iterations of this it finally worked.
Dave was very low vision even then. It's amazing he did as much as he did without the modern low vision aids. We used to joke that he would wire his nose into the back panel of the concentrator since he had to get so close to see the pins. In recent years I, too, have become low vision and Dave is my role model in this regard too. He had an unusual form of childhood glaucoma. For years the doctors kept one step ahead of it and he kept some vision, but when I EMailed him recently I learned that he had become completely blind.
For a few months Dave and I were the only consultants on the help desk at the Computing Center for one or two shifts a week. We had a lot of fun, but it must have been an odd experience for the students who came in for help with their MAD programs.
In spite of his vision problems, Dave was an avid photographer. In fact he took the picture of me at the 360/67 console that is floating around the Internet. Dave and I both went to Israel in 1969 with Bernie Galler's seminar series and spent a lot of time wandering around in our free time. Dave used to have photos from that trip up on his web site.
He was one of the most interesting and smartest people I have ever known. He will be missed by all who knew him.