Rick Shoemaker, quantum magician and microcomputer whiz

This post summarizes what I said at the retirement ceremony for my long time collaborator and good friend Dr. Rick Shoemaker, Associate Dean, College of Optical Sciences, and Professor of Optical Sciences.

I’ll talk a bit on Rick and his love for microcomputers. Back in the 1970s, Rick regularly performed magic in nonlinear spectroscopy. For example, he used to pull beautiful photon echoes out of the noise. Photon echoes had been observed before, but with relative difficulty. Photon echoes are useful for measuring the lifetime of induced dipole coherence. How did he observe them? For a single pulse, pulse, echo measurement, the oscilloscope time trace would show nothing but noise. But Rick performed the measurement many, many times, adding the results. Since the noise was a random function of time and the echo was deterministic, the echo rose up out of a sea of noise.

Ordinarily such techniques involved expensive Tektronix or HP lab equipment. But Rick had a better, more fun way. He assembled a Z80 microcomputer and taught it to do the adding, any time night or day! It worked in spite of the fact that Rick had defied all odds and packed a whopping 64 KB RAM in his computer! At the time I had built a Z80 microcomputer to computerize my home and had been collaborating with Rick on some debugger software. We decided to pool our thoughts and write a book on interfacing microcomputers to the real world. We used the fledgling word processor I had coauthored (with Mike Aronson) in Z80 assembly language and typeset it on our microcomputers using a daisy-wheel printer. At that point, Rick started teaching his popular course on microcomputer interfacing based on the book.

Then in 1981, IBM faked us out with its remarkable, very non-IBM-like PC, and naturally we had to write a book on it and typeset the book on our new IBM PCs. The PCs included a Microsoft 32 KB ROM Basic, configured to graph things on a 320x240 color graphics adapter, but not on the nicer 720x350 monochrome adapter. Shortly thereafter, a start-up company named Hercules came out with a compatible monochrome card that included graphics functionality, but no support for Basic. Not to be discouraged, Rick and Chris Koliopoulos (the Ko of Wyko Corporation) fixed this lamentable limitation by copying the ROM Basic into the unused upper half of the Hercules card’s 64 KB video RAM, patching some locations, and bingo, they could graph things using Basic on the Hercules card. Naturally Hercules wanted this software really badly, paid the inventors accordingly, and bundled it with their card. We all had many fun times together at Comdex Shows and elsewhere.

Twelve years later Rick and I wrote an updated book on PCs of the time. Yet another 12 years have passed since then, but Rick and I have never lost our enthusiasm for microcomputers, old or new, although admittedly Rick has succeeded in controlling his computer addiction better than I.