Interview by Curt Vendel of the Atari Museum.
CV: How did you get involved with Atari and the 2600 project?
JD: I was hired in December 1975. I started
working for Steve Mayer and Ron Milner at Cyan in Grass Valley CA.
- My first job was to help debug a concept prototype for what became the 2600.
This was hardware and software (Ron did the hardware, Steve did a Tank prototype.)
- In March of 1976 I moved to Los Gatos CA to apprentice for Jay Miner, the lead chip designer.
(The whole team moved to Sunnyvale in the fall of 1976.)
- Redesigned the hardware with Jay, built & debugged the hardware, rewrote the core of the Tank game.
This included the system desing: 6507, 6532, TIA, controllers, cartridge slot, etc.
- Designed the sound circuit on the TIA chip, based on Ron Milner's prototype.
- Wrote Video Olympics cartridge fromt the ground up, as a piece of test code and then as a product.
(Larry Wagner, the lead cartridge programmer, did a great job of reinventing and productizing the Combat
cartridge, including Tank, Jet Fighter and BiPlane.)
- While the basic 2600 chip and system were in production pipeline, we redesigned it to work on PAL TVs, so
we could ship them to Europe. Big contributor: Niles Strohl.
CV: Wow, so you really had
your hand in the project from the ground up. Once you completed
the work on the
Atari 2600 project, what type of work at Atari did you do next?
JD: In the Summer of 1977,
I went back to Grass Valley to work with Ron and Steve on the next generation
the progenitor for the Atari 800.
- Went back to Sunnyvale to rethink the "Colleen" product as a system with partitioned chips.
- I worked with a guy name Francois Michel to design the ANTIC chip.
- George McLeod designed the CTIA (Colleen TIA) and Doug Neubauer designed the POKEY (POtentiometers
and KEYboard interface.)
- I wrote some games as test code, but none shipped. The most interesting technically was a implementation of SuperBug.
In this game, a car is in the center of the screen, and the entire enormous driving course scrolls around it.
- I worked on the SIO bus, the Atari SIO was bound by how fast we could run the wire, how well we could shield it, and how
much intelligence we could put outside. It was a kludge, running at 19,200 bps.
There is an interesting and true story here:
At the same time that we were designing the Atari 800, the Apple II was
on the market, and popular. It had slots, and we badly
wanted to have slots in the Atari 800 (then called Colleen).
Atari was dealing with the FCC under the Part 15 Type I rules, for anything that actually generated TV channel RF. Those radiation
rules were much stricter then the Class A and Class B rules that common computers must meet, so slots were out, and we ended up
wrapping the electronics in a 2mm thick aluminum casting. The serial bus was our way of adding peripherals. (It was also a very
expensive one. I think it sank the product.)
Meanwhile, Apple was dodging the FCC, by not including the RF modulator
themselves. You had to buy it from someone else and
install it yourself.
So, in early 1978, a TI salesman walked in to try and sell us a cheap fiber
optic cable with a transmitter molded on one end and a
receiver molded on the other. The idea that I had was: if we build a computer which is optically isolated from the TV, then we
can just put the bundled fiber receiver and RF transmitter into the FCC for approval, make a really quiet fiber-to-RF converter.
We could then do whatever we want in the PC including having slots. I told this application to the TI sales guy whose eyes almost
Our engineering manager (Wade) said "No, the FCC would never let
us get away with that stunt." The TI salesman went off and
people anyway, including the team we didn't know about who were designing the new TI 99/4 home PC.
TI went to the FCC in 1979 trying to use the same idea. The FCC said
NO WAY. There was a big stink, because TI's home
congressional district was represented by the then Speaker of the House Jim Wright, a powerful man.
Wade was jubilant. He said I could not have sabotaged TI better if
I had tried. The result of the whole mess was the generation
Class A and Class B specifications.
CV: So not only did
you work on some of the most important early projects at Atari, but you
helped to cause a set back with TI's release of its
home computer. Well I'm sure everyone will appreciate your stories of the work on the Atari 2600 and the Atari Colleen SIO bus. Also
I would like to thank you for your generous loan of the HUGE 6' by 6' photoplot of the TIA which was on display in the Namco Museum at
the World of Atari 98' show this past August in Las Vegas.