A Bill Rose Conversation
by Geoff Oltmans

> -----Original Message-----

> From: Geoff Oltmans

> Sent: Friday, March 12, 2010 5:11 PM

> To:

> Subject: Greetings!

Hello Mr. Rose:

Believe it or not, I stumbled across your name while perusing some source code that you helped write for the Coleco ADAM Master 6801! I just wanted to give you some kudos for helping to create one of my favorite home computers. This machine more than any other shaped my interest in computing technology as a child.

I now work in embedded system design at a company called ADTRAN. We design telecommunications equipment. In my spare time I like to dissect your work on the ADAM, and have been porting Marcel de Kogel's excellent ADAM emulator to work in Mac OS X.

I just felt it necessary to write to you and tell you how much I have personally enjoyed using the ADAM these many years. :)



> From: Bill Rose

> To: Geoff Oltmans

> Sent: Mon, March 15, 2010 1:14:51 PM

> Subject: RE: Greetings!

Hi Geoff

Wow that's a blast from the past. Didn't know anyone outside of a few at Coleco knew I wrote code for the Adam. I actually designed much of the hardware. My code was primarily the drivers specific to my hardware design. It had to be written in assembler to operate efficiently. The hardware had some very specific requirements that few of the software team were able to fully understand to write the code. Very timing specific to handle the DMA without impacting the Z80's operation. In fact they tried to rewrite it but ended up going back to my original code. Long story there.

Nice to know someone remembers the Adam. It was pretty revolutionary at the time. Its undoing was trying to go from initial schematics to shipment in 4 months. Took us about 8 months to get it stable but by then it was too late. The early shipments were too buggy to survive the bad reviews. Very long story there.

I still have mine though it is in storage at this point. I also have some game screens in EPROM for Zaxon and others that were never released.



> From: geoffrey oltmans

> Sent: Monday, March 15, 2010 2:46 PM

> To: Bill Rose

> Subject: Re: Greetings!


I actually started disassembling the code from dumps I made from the actual MCUs, but ended up getting a set of the source code for several of the 6801 MCUs from another fellow ADAM tinkerer on the Coleco ADAM mailing list. These were all listings from the ADAM Technical Manual apparently. The combination of the MIOC/6801 and ADAMNet implementation are probably the most interesting aspect of the system to me. That and the tape drive implementation, which seemed like a novel solution to the relatively high price of disk based storage of the time. It probably didn't hurt that it played Coleco Vision games which I also loved at the time. ;) Anyway, I've never seen any other home computers from the time frame that had a serial communications channel for the expansion devices that was DMA'able. I also like that it was generic enough to support a wide variety of different devices. I have kicked around the idea of making a USB->ADAMNet adapter so that you could use real ADAM peripherals with the emulator on a PC, or alternatively use a PC to emulate peripherals on a real ADAM system since they are relatively scarce. Probably would use something like a Coldfire microcontroller maybe (since I've got a neat little SBC prototyping board from Freescale anyways), or dirt cheap like a PIC. I'm new to the world of USB, so I figured that might be a novel idea for a learning tool. Did you also write bits of the EOS code also?

It is a shame that the system couldn't overcome the initial bad reviews. Bad news travels faster than good news unfortunately, and I guess they were so concerned about missing out on the Christmas buying season that slipping the ship date was politically impossible.

I think I may have seen a dump of a demo cartridge (store demo maybe?) for the ADAM that showed off a lot of different software they had planned. Might be the same thing you're talking about. Couple quick questions for you... I have seen a picture of alternate ADAM console pictures from the CES prior to release. It looked like it had slot-loading DDP drives similar to a car cassette player. Does this sound familiar? Also, is it true that the ADAM started out life as the Super Game Module attachment for the Coleco Vision, and then morphed into the computer design, or were they completely separate designs?

Nice to be able to put a (virtual) face to a design like this. :)





> From: Bill Rose

> To: geoffrey oltmans

> Sent: Mon, March 15, 2010 2:41:41 PM

> Subject: RE: Greetings!

The serial network was my work. The original used the Z80 to 'bit bash' RS232 ports to each peripheral. I did a quick calc and found there were no where near enough instruction cycles in the Z80 to also run the OS and word processor. I designed the DMA at home in my 'free time'. We switched to the new design in early May but management insisted we had to ship in Aug. There was no hardware, drivers, or software when we switched. i.e. 4 months to do it all. Obviously not possible. At one point mgmt asked why we weren't shipping (around October). The answer was "they are all failing fina test". Mgmt then informed manuf to cease final test and ship!!! Bad decision.

The game screens I referred to were in development when we announced we were exiting Colecovision as well as others we developed for distribution using the Adam's tape drives. I ran game design as well as hardware and software development at that time so I got early releases. These are screens that have never been seen by the public. Actually I haven't looked at them in years.

As for your questions, Adam was supposed to use miniature endless loop tapes - much smaller versions of the 8 track tapes of the 70's. Problem was reliability. They jammed just like their larger cousins. We could never get them to operate for any length of time. We scrapped them for the cassette tape drives. These were similar to standard cassettes except we added some holes that were used to align them and hold them in alignment during high speed operation. We operated at 20 ips (inches per second) with FFD/RWD at 80 ips. Standard cassettes had too much movement to keep the tape in comtact with the head. We also had to use higher quality tape - basically "first run" tape to minimize defects in the magnetic media. First run means the first batch of tape coming off a line. The bath they use to coat tape degrades as it is used. Similar to high quality video tape.

The expansion module was actually a nearly complete Atari game system. About all we used from Colecovision was the power supply and perhaps the video modulator (I forget the details). It gave us full compatibility with Atari games because it was an Atari system. I don't think the Z80 or graphics processor was used for anything when using the module. Adam was a completely separate effort. No relation at all. It was the time of the Timex/Sinclair, TRS80 (pronounced Trash 80), Commodore VIC-20, and Commodore 64. Home computers were getting big and Coleco wanted to be a player. The initial design was simply a Colecovision with the RS232 ports added, the endless loop tape drive, a printer, and keyboard. The idea was that it was a computer with a real operating system and word processor out of the box. No need to program in Basic. I was hired to work on that design. See above for where it went.

We did design (paper only) an ASIC that would allow the Z80 to emulate an IBM PC. The designer, a kid fresh out of college, was Steve Perlman who later went on to found WebTV and MOXI. We killed the project before implementing it.

As I said, lots of unwritten history here.



> From: geoffrey oltmans

> Sent: Monday, March 15, 2010 4:01 PM

> To: Bill Rose

> Subject: Re: Greetings!

I think you're referring to the Expansion Module #1 (Atari 2600 compatible) that was actually released. It was as you indicate practically a standalone system other than using the RF modulator and the power supply from the Coleco Vision. I was referring instead to this gadget (great pictures here, overlook the inflammatory language about the ADAM <g>). It used presumably the same wafertape/floopy drive you're talking about with the original ADAM drives...


I see they also have a picture there of Super Zaxxon in CED videodisc form. I had found an article about Coleco making a videodisc capable system, so there was some early confusion among the hobbyists about whether it would be videodisc or wafertape based. I guess they tried both?

Very interesting info about the IBM PC compatibility mode! I can see how that would have been in the works. Seems like everyone up to and including the Amiga tried to make a hardware option for that if they couldn't do it in software.

I love a good story... I'll bet the home computer/PC industry was interesting to work in (and probably somewhat stressful at times) back when it was still hot.


> From: "Bill Rose"

> Date: March 15, 2010 4:44:23 PM CDT

> To: "'geoffrey oltmans'"

> Subject: RE: Greetings!


Oh that one!! Another great story. The microwafer drive was the endless loop I mentioned. Didn't work. The Supergame Module was supposed to be based on that but as CES neared we realized it couldn't cut it. The unit that went to CES had to use ROM'd games "under the covers". The tapes only held the ROM bank select number repeated over and over. We would simply read the ROM bank code off the tapes, delay starting the game for a period of time and then play it from ROM. Had some quirks too. If someone removed the tape during play and put in another tape, the old game continued to play unless they hit reset. Some uncomfortable moments in front of press as the demonstrator screwed up. The rest is history.

As for the "Super" games, we released some of them on Adam tapes for play on the Adam. I still have Super Zaxxon and others though I doubt they still play - the tape drives were a bit "finiky' even then. I know one of our old techs who still has copies of almost everything we ever developed.

We did release a floppy drive for the Adam toward the end but too late to save it. Also too expensive.

We did work on an optical disk game system but the games were very poor. The problem was the disks were really video disks so the games attempted to use branching based on the player's moves. Do something and branch to another video scene, do something else, branch again. Seel times were slow so you had to wait a few seconds to see the next branch. The video processing at the time was too limited to seemlessly add game play or over lay the video. Also they were not good as data disks (no real data format) so loading data took some work. Killed that one too.

What no one knows is that we also developed an Apple II knock off in 3 chips. However, following on the heels of Adam, the banks wouldn't loan the money to go into production even though we did complete the design, ASICs, built prototypes and had negotiated with JVC to build it. It was a land mark machine. It used the Windows concept before the MAC was out (no one knew to call them

Windows and we never patented the idea) - drop down menus, etc. It also included a 2400 baud dial up modem and a phone. We could play head to head games over the phone lines, download/upload files (even unattended over night), etc. Pick up the phone, your contact list would pop up - in the middle of a game!! Make the call by pushing a button or dialing and then resume the game.

Touch the calculator keypad and a calc would pop up on the screen, etc. The case was designed by Porsch. Very cool and way ahead of its time. We had working models - don't know what happened to them.

Also developed a next gen video game system - 32 sprites per line (Colecovision had 4), much better graphics, colors, and sound.

But the real kicker were the 4 vector engines that used the graphics engine for background graphics. The vector graphics created the space ships, etc. on the full graphics background. I believe we could handle 2K vectors at 30 frames per second. And with the integral dial up modem, we could play real-time head to head games with multiple players over phone lines since each player would put up his own background graphics and simply send the vector information (very compact) over the phone. Unfortunately Coleco exited the video game market before we could launch it. But we did have working prototypes.

They were exciting times. I ran Advanced R&D and had a team that eventually broke up and went to Sun, Apollo, Apple, Intel, and others.

Very talented team. We did some Artificial Intelligence work as well for products like the Talking Cabbage Patch Dolls (each doll had a digital RF network to let them coordinate their scripts - they talked to each other, sang songs together, etc. Another Coleco first was Laser Tag which was eventually released by Worlds of Wonder.




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