d
i
g
i
t
a
l
digital equipment corporation · maynard, massachusetts
MEMORY ADDRESS
EMA
RUN

Kendall Auel's PDP-8 Memories

My memory is a bit faded from 50 years ago, but the experience helped launch my software development career that is now in its 40th year and going strong.

My mother and father both worked for Tektronix when I was growing up in Portland, Oregon. At that time, Tek had its own education department. They taught a variety of technical and personal interest classes. All classes were free to employees -- and their families -- which was an incentive, for example, to bring your wife to a gardening class while you learned about calibrating oscilloscopes.

At about age 10 or 11, I learned a little about BASIC programming at the Oregon Museum of Science and Industry (OMSI). Impressed with my interest, my father decided to sign me up, as an 11-year-old, for the PDP-8 class being offered at Tek. This was in 1971. The class was at the Tektronix Beaverton campus, in the early evening, in a small conference room that smelled of cigarettes and coffee. My classmates were mostly electrical engineers working at Tektronix. They were kind of amused that a kid was sitting in. The fundamentals were taught first, binary and octal number systems, branching and looping logic, conditional branches, etc. Finally we got to see the machine. This memory really sticks in my mind. It was very exciting, the blinking lights and toggle switches, very space-age. I was very excited about Apollo and the space program back then, also.

At home I could hardly think of anything else but the PDP-8. I spent hours upon hours reading the programming manual and working on my homework problems. My classmates, with full time jobs, wives and children, houses to maintain, cars to fix... I don't think they had the free time of a young kid with few responsibilities. The first assignment was kind of simple, set bit zero in the accumulator, shift it right a bit at a time until bit 11 was set, then shift it left until it was back to bit zero. Then loop, which would send a little red light running up and down the front panel of the PDP-8. I worked this problem in my mind and got the whole thing down to maybe eight or ten machine instructions.

By class time I had my little sequence memorized and could hardly wait to try it out. The instructor asked who had done the assignment, and there were lots of sheepish looks from my classmates. I raised my hand, and said I was ready. In the machine room I walked up to the front panel and toggled in my program from memory. I remember being so excited to hit that run switch. I toggled the switch and... the red light started racing back and forth! You could hear a pin drop. You ... memorized the program? Well, it was only eight instructions, so...

As far as I can remember, all of my classmates finished every assignment from then on. If this kid could do it, they surely could.

Kendall Auel
Wilsonville, Oregon