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The Interview
PERSONAL



Q: Could you tell us a little about yourself? Your studies? Your job?

I have been doing electronics since prior to the fourth grade when I received an Electronics 50-in-1 kit where you could hook transistors together along with resistors and capacitors. I remember studying the transistor and how it worked until I could picture the flow/valve action of it. I also remember trying to get my mind around how a capacitor worked when I was in the second or third grade. I remember deciding that you could feel the "push" from the other side of the plate but only when you changed the push (I.E. AC) Later I figured out that removing the pressure would work too. I also stuck my finger across the leads of a the flash bulb of a strobe light that belonged to my father and getting a shock even though it hadn't been turned on for a while. I decided that the big blue capactitors acted like high voltage batteries.

I was fixing TV's by the time I was 14 and had a back yard full of TV chassis much to my mother's dismay. Kids all around my small home town in Indiana knew to drag any chassis the found over to me.

I dropped out of High School as they wouldn't give me any of the electronics classes I wanted, they didn't believe I was "academically inclined", what they had missed was the fact I wasn't stupid. I joined the Army National Guard and was trained as a Teletype repairman in addition to soldiering. I ended up a tanker and then a medic later.

I started in a factory that made digital Scales as a test technician. I worked my way into Engineering by studying what the failures were in production and instead of just bitching about them I wrote them down along with proposed ways to do it correctly. Eventually I was designing microprocessor based instrumentation by the ripe old ages of 20 and 21 and had more experience at it then kids who weren't due to get out of collage until they hit the ripe old age of 23 to 24.

My boss and I stopped getting along. A friend of mine named Hedley Davis, who later joined CBM told me about an opening at Commodore and I ended up with the 1000-1 shot of landing a job there.

Q: What was your first appointment at Commodore?

I was supposed to write software under Benny Pruden for disk drives since I knew 6502 assembler real well. Benny was out my first week and I wondered off to the hardware lab where I ran into the project known as the TED. The guy on it had inherited it and he was leaving. As it happensI had been experimenting with the same type of shared bus structure at home and one thing led to another. I ended up in charge of TED while still figuring our what it meant to work for Commodore, I was young, niave and full of youthful enthusiasm. I worked 12 hour days and drove an hour and 15 minutes each way.

Q: Are you still meeting any of your ex-colleagues at Commodore?

Bob Russell who did the software for the VIC20 and the C64 and ran the Z8000 project works as my CTO. I run into Dave Haynie ever so often and once or twice a year the old engineers get together that include Freddy Bowen, Greg Berlin, Haynie, Andy Finkle and others. Terry Ryan started an ISP at the same time I did and we keep in touch.

Q: When did you leave C= and why?

I was tired and burnt out and yet wanted to keep doing cool things. I made a mistake by leaving and joining a company that neither had the capability of doing the things we did at CBM nor did they quite know what to make of my behaviour.

Q: What was your task exactly with the TED machines? You mention in your presentation held with Dave Haynie that first you had been put to the software team to be reassigned a little later to the hardware guys.

Software for something compltetely unrelated and then the hardware for TED> The core design was done since it was based on the Chip itself but it was suprising just how much needed to be done from there. I taught myself Japanese and learned Japanese production methodology through the TED preproduction and so knew a lot about how to design for production when I started the C128.

Q: What is your personal opinion about the TED machines?

If sold for between $49 and $79 as they were designed to do they were kick-ass little machines. Very powerful Text Based machines for the day, as in TExt Display, as not meant to compete with the C64 at all.

Q: Have you followed a little how the Commodore plus/4 scene evolved over the years? Do you know there are still games and demos made for this platform? Ever tried an emulator (if not, maybe a C128 emulator)?

No I havn't. It makes perfect since to emulate as that processor systems run 3,000 times faster. Someone once asked me why I don't keep a C128 running to do any work on at all and my reply was that as an engineer I would use whatever technology gave me the best results, I.E. if I could load an emulator to play jumpman, why would I blow the dust off of a 1.02mhz processor.

GENERAL



Q: Why, when and how exactly got the 264 line actually folded by C=?

Couldn't actually tell ya, they were probably still running somewhere when I quit. I know that Comb was selling them 3 years later at $79 each which made me smile.

Q: What ideas, technologies you have actually utilised from the TED series when making the Commodore 128?

Well I got the idea from the fact that the TED wasn't compatible with the C64 that the next (and last) 8 bit entry should be C64 compatible as a minimum. By the time I started the C128 I knew the production culture of CBM very well and got my hands on the super-secret inventory list of parts that CBM owned. I literally designed the C128 from what was in stock, what we had paid for it and how many we had. That is why there are so many 7406/7 type parts ($.03 each) and why there were no PAL chips like 16L8's I simply wouldn't have even known this list existed or the significance of it if I hadn't done the TED.

Q: Has compatibility with the TED series ever been considered in the C128 (like with the C64)?

Nope, not at all. TED was a single chip system (okay 9 chips) in a footprint the size of a Sinclair (ala C116). It was designed to sell for $49 while the C64 sold for $299 and later $199.

Q: There's actually a TED patent filed under Pat. No. 4569019. Could you tell us some background info on this or was it before you actually joined C=?

Didn't know there was a patent but that would have been a standard thing to do. I just hit the Patent site and clicked on one of the relevant references and the guys who did TED Were listed. Dave DiOrio was my best friend back then.

See the patent here: http://www.freepatentsonline.com/4569019.html

Q: Are there any untold stories about the TED series you might wanna share with us? Some anecdotes maybe?

Well lets see... There were a couple of strange things that TED did the first time we got the computer near a monitor. The first was the picture would get black specs in it when the main board got too close to the monitor which is a pretty noisy source of radiation and radio. I threw it on an analyzer system that I had put together and very quickly saw the clocks freezing. I walked into the chip guys and said (not asked) that they were using one of the pins as a "test" pin and that by giving it a voltage you could freeze TED or reset it's counters. This is so the test vectors of the chip testor has a known starting place when it watched the chip for proper performance. They were pretty shocked that IO had figured out their "secret" function on the chip and more so that it was causing problems. I had already fixed it by adding an external resistor to lower the impedance on the pin. When they said they had tied it off also which is why it shouldn't have been a problem I basically related that the NMOS pullup resistors looked like a high impedance instead a high voltage EMC field and that a more tangible "carbon" part was need

Then one day the new joysticks arrived. I hadn't plugged a joystick into the system early on, we didn't have any made that fit the plug and we didn't really have any applications that even read the joystick. Besides what could go wrong, right? Well it turns out the design as I had inherited had the actual datalines going down the joystick cable. (Oh, when the said D0-5 on the schematic they meant THOSE D0-D5 lines) Well the data lines didn't like going down a cable they especially didn't like getting near a high voltage radiant field. Spots again in the video, nasty ones. My boss and I were arguing about shit anyways and he got short with me when I started to explain what was causing the problem and said "fix it!" Less than an hour later he walked in and started to raise his voice at me again as he thought I was just standing there playing video games when his bonus was on the line. I just pointed to the video cable. He looked look, started to open his mouth and I pointed again and he finally asked what the fuck he was looking at. I had had one tech modify the computer with an additional chip to buffer the Data lines and I had another tech add a 10 foot cable to the joystick. I had then taken the cover off of the monitor, and being an ex TV repairman, I knew how to safely wrap almost the entire length of cable around the yoke and neck of the picture tube itself. In short you could not get a more extreme example of working in the radiation field of the high voltage circuitry. When it finally dawned on him that that proved it was fixed once and for all he just harummphed and stalked out.

Q: Do you still remember who did what in the TED machines?

Dave Diorio, Bruce Aherns, Bob Raible, and Eric Yang did the chip, I finished the hardware design with help from Haynie and Freddy Bowen, Terry Ryan and John Copper did the software (Kernal, Basic and drivers respectively) Later Hedley Davis would fix a lot of stuff in the cassette routines that had been rewritten.

Q: Could you also forward these questions to Dave DiOrio, maybe? :-)

My last email for him bounces.

VIDEO



Q: How was the palette of the TED determined? Was the VIC-II palette some kind of a basis in any way? Or rather the VIC-I?

Nah, just 8 bits represents 8 distinct hues if you count gray as a hue. There are actually 121 colors because 8 shades of black is still black.

Q: The TED shows quite a lot of similarities to the VIC-II. Was a stripped down VIC-II the basis for the TED (in chip layout etc.) or these

Not at all, designed from ground up, different DMA, no spites, sound as a shift register, built in PAL mode instead of a different version of the chip.

Q: You still remember how exactly the colour and character DMA have been implemented in the TED?

I was going to say that there wasn't DMA and then I remembered that they did do a color character pointer fetch once per character that determined what the foreground and what the background colors were, then the video data fetches during the low part of the clock cycle were actual video data.

Q: To current knowledge, there has been three TED revisions in total (R0-R2). Do you happen to know what the differences were?

Bug fixes.

Q: Do you think someone is still having the final TED specs? It'd be of enormous importance if that could be recovered.

(Edit: no answer provided)

Q: Someone has achieved 400x400 pixel resolution with the TED machines instead of the normal 320x200 one, purely from software. These are all possible due to the fact that almost all internal counters are available as writable registers. Why did you guys make that possible?

Why not? :)

Q: You happen to know what the TEST bit actually did in the TED? The C128 has this bit, too.

For resetting it to a known state for the chip testers.

SOUND



Q: In the TED patent they mention 2 square wave generators PLUS a noise generator. What was the reason to cut the TED's sound capabilities even further, down to 2 square waves of which one is switchable to noise? Had an envelope generator ever been considered?

Wasn't a game machine, it was a 9 chip machine with no analog circuitry or supplies.

Q: TED sound is not very advanced, although still far better than the potential opponent's (Sinclair) beeper. How much time has been actually invested into engineering it? :-)

It was actually a point of contention. Terry Ryan wrote a memo about the "racous squacking noises" that came out of the Ted chip. One of the bug fixes was that the "random" patter for the white noise generator wasn't random... so they seeded the registers in the shift register chain with random values, otherwise there were cyclic tones you could hear instead of just noise.

Q: Are you aware that plus/4 hackers actually wrote a digital SID "emulator" for the plus/4? It could do all 3 SID channels with all standard waveforms and envelopes.

Cool.

SPEECH



Q: Why had the Speech prototype (V364) been canned? Who decided that?

There was noone really steering the ship at the time. Tremiel had left.

Q: Why Toshiba's T6721A speech chip had been chosen for the V364?

The speech was actually developed by the guys that did the revolutionary TI Speak and Spell. Ken Brightman and Dr. Richard Wiggens. What function the Tosh part plays in the D/A conversion and the manner in which it was encoded was done by them

Q: You have any info on how the V364 actually communicated the speech paramters with the Speech chip? Did it use software or hardware filter parameter decompression?

Brightman and Wiggens had developed some kind of sound tokenization for sound data, they would then sample the data and compile it on a VAX. Note that Purple came out "Gurple"

Q: The MOS 8706 R0 a custom ASIC in the V364, was designed to replace the rather complex glue logic found in the Magic Voice cartridge. You happen to know something more about it?

Yeah I do. The guy doing it had to learn the hard way about gate array design and he invented the "texan write" where you have to write the same value to the same location twice in a row to make it do something immediately.

Q: Was Toshiba's speech chip (T6721A) much different from the one featured in TI's famous Speak'n'Spell toy (the TMS5100)?

Not sure. See above.

Q: Was there actually software being made for the V364? How about the Magic Desk? Was its development also underway for the V364 and later put on hold?

We demo'd talking Magic Desk for K-Mart and others at CES.

Q: Are still in contact with Dr Richard Wiggins? Do you think he could also add his thoughts here?

Havn't heard from him since the old days.

Enjoy.

Bil

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