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Technology Associates and the Story of Intellivision Bump ‘N’ Jump

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You may be aware from updates to the Intellivision development history that I’ve been in contact with Joe Jacobs and Dennis Clark for a while. They have provided some background to the creation of their PlayCable development system and the subsequent work on Bump ‘N’ Jump. This posting details the story from Joe and Dennis’ perspective and I’d like to thank them for helping me to put it together, and allowing it to be shared.

 

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Joe Jacobs & Dennis Clark Circa 1980

 

Joe Jacobs and Dennis Clark are engineers who worked for Jerrold, the cable television division of General Instrument and manufacturers of PlayCable. Dennis joined Jerrold in the summer of 1978 working in Hatboro PA. Back then, in the early days of PlayCable development, Jerrold anticipated that, like Mattel, it would write games for the Intellivision to be distributed over PlayCable. In part, Dennis was recruited to go into arcades and scout for titles suitable for conversion. As it turned out Jerrold never wrote a game for the PlayCable, and Dennis did not make it to an arcade on company time. Instead, he worked in the Software Department writing firmware for cable boxes and PDP-11 software for Jerrold’s cable head-end infrastructure. Development of the PlayCable hardware was well advanced by the first half of 1979, and over the summer Dennis worked to develop the firmware for the PlayCable adapter. He was also responsible for the music tracker used by the PlayCable menu program, and he arranged the version of The Entertainer that can be heard playing on the splash screen of the menu.

 

 

In early 1981 Joe Jacobs left Siemens, where he worked on automated test equipment. He was hired by Jerrold to work in their Head-End Division as a Project Engineer to develop hardware and software associated with the distribution of cable services. This equipment was used by cable companies to distribute and control their subscribers' access to channels. The systems that Joe worked on communicated with the converter boxes installed in customers’ homes that Dennis helped to develop. Whereas Dennis is primarily a software specialist, Joe is more of a hybrid engineer, his focus is on hardware development, but he also writes software. Although Joe and Dennis looked after different aspects of Jerrold’s products, they worked in close proximity to each other, and became good friends. Dennis recalls how Joe nicknamed him “Grumpy” because he always had a determined look on his face. Joe explained that “In the early 1980's, Jerrold was still a small to mid-sized company and most of Jerrold's engineering was in one building”. Dennis says that, under the management of Charles Dages, Jerrold’s engineering department was very supportive of engineers’ creativity and fostered collaboration.

 

It should be noted that when Mattel partnered with Jerrold to develop the PlayCable the two companies had a symbiotic relationship. Jerrold brought hardware knowledge specific to the cable industry and Mattel supplied access to the secret sauce for the Intellivision. This included the APh assembler and linker, and details of the EXEC and how to use it. Joe describes a “HUGE listing called the Mattel 'EXEC'. This listing was an assembler list file generated when Mattel compiled the library routines that went into each and every Mattel Intellivision main unit. It was dot-matrix printed, on that wide paper with the holes at each end and was about two-inches thick. It described each and every routine available to the game developer, calling conventions, parameter passing, object creation and interaction, etc”. Dennis noted that the interrupt driven model of the Mattel EXEC was unusual for the time and something he thinks was very innovative. Although General Instrument could provide Jerrold with information about the Gimini chipset on which the Intellivision is built, it needed these Master Component specific resources to write software for PlayCable. Remember that Jerrold had to write the firmware ROM in the PlayCable adapter, the menu program used by customers to select games, and potentially original Intellivision titles. Therefore, Jerrold, like APh, was one of a small number of trusted partners, and Jerrold engineers like Joe and Dennis had an inside track on writing software for the Master Component. Interestingly, Dennis recalls that during the development of the PlayCable he visited APh in Pasadena to learn more about the Intellivision, a trip that led to him meeting Glen Hightower and the Intellivision developers.

 

It seems that at some point in late 1979, one of Dennis’ colleagues, possibly Joe Rocci, realised that the head-end infrastructure could be used to create backups of Intellivision games that could be played at home. PlayCable games were transmitted from dedicated microprocessor controlled cards, housed in a PDP-11 minicomputer. These same cards were also used by cable company head-end systems to communicate with consumers' cable boxes. A side effect of the encoding scheme used to transmit PlayCable titles was that the game data could be recorded directly off the transmission cards onto a regular audio cassette. The image below shows one such a DCX11A (Dual-Channel Xmitter) card connected to an audio adapter that was used to record Intellivision games.

 

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DCX-11A DataChannel Transmission Card with Audio Adapter

 

Jerrold engineers could load games into the transmission card, connect the digital output to a tape machine using the adapter box and record the resulting stream. At home, they could then connect a regular audio cassette tape machine to a hacked PlayCable adapter and play the recorded game directly into the PlayCable’s memory. To make this work required some changes to the PlayCable adapter firmware, and for the digital board within the adapter to be connected to an audio input, rather than the normal cable receiver. These hacked PlayCable adapters were based on the earlier, limited-production Jerrold model which, unlike the later PlayCable branded units, had their digital sub-system implemented using standard off-the-shelf components. This made them much more hackable by exposing their inner secrets to those in the know, or with access to oscilloscopes and datasheets (see Sections 8.1 and 8.2 of the PlayCable Technical Summary for more information). Jerrold’s engineers christened these audio backups “PlayTape”. This innovation gave unrestricted access to the entire Intellivision PlayCable games library and was shared amongst some of the members of the engineering department. As Joe says, “all of us engineers had a modified PlayCable setup so we could play Intellivision at home. Remember, at the time, Intellivision was the ‘cat's meow’ of video games, handily beating the Atari 2600; Colecovision had not yet come on the scene”. Dennis believes that the management of Jerrold’s engineering department were probably aware of what their engineers were up to, but turned a blind eye, not seeing any harm in it. 

 

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Title Screens for the Standard PlayCable (left) and Joe's PlayTape (right)

 

On joining Jerrold in 1981, Joe quickly discovered what was going on and got involved, contributing to the modified firmware that ran on the PlayTape adapters. Before joining Jerrold, Joe had put together a small PDP-11/03 “Frankenstein” system of his own at home. This was compatible with the computers that were used to develop Jerrold’s cable head-end software and write Intellivision games. Through the summer of 1981 Dennis continued to tinker with Intellivision development, stripping sounds from Mattel games and building a sound board application to play them back. Joe’s interest in video games led him to start reverse-engineering the Arcadia Supercharger following its release for the Atari 2600. He figured out a way to read some of his Atari game cartridges and transfer them to the Supercharger replicating the “game-backups-on-tape” principle behind PlayTape.

 

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Catalogue of PlayTape Titles

 

Through the fall of 1981 the library of PlayTape games was extended as new titles were released for the Intellivision, the pair also wrote diagnostic programs, and started to investigate the inner workings of the Intellivision’s EXEC. Joe realised that it would be possible to use a specially-modified PlayCable adapter, along with his Frankenstein PDP-11, and the tools he had access to at Jerrold, to develop rudimentary Intellivision games. Inspired, Joe suggested to Dennis that they "try and write a game for the Intellivision". Dennis was up for the challenge and explained the methods Jerrold used for Intellivision development. Joe recalls that the process was pretty simplistic. “It wasn't a whole lot, in my mind, it was basically EPROM burn and crash and burn and crash and... development".

 

By this point Dennis also had a PDP-11 at home, put together from spare Jerrold equipment. Building such home systems was supported by Jerrold, as it allowed engineers to continue to work on company projects in their own time. In the meantime, Joe had started to think about how to improve the development tools, “I was, and still am, an in-circuit emulator kind of guy and prefer to do my software debugging in that environment if possible”. According to Dennis, testing was done using “something like ROM simulators to load the code from the LSI-11 to a modified Playcable type adapter”. This allowed test code to be uploaded from their development machines directly to the PlayCable, bypassing the need to use a broadcast card and audio cassettes. Joe says that “the whole concept was loosely modelled on the then-popular Motorola ExORciser development environment”

 

In the spring of 1982 Dennis and Joe concluded that they needed a demonstration to showcase their maturing Intellivision development capabilities and grab the attention of Mattel. They tossed some ideas back and forth and settled on writing Clone-Man, a homage to PAC-MAN. At the time PAC-MAN had just been released on the Atari 2600 and was at the forefront of public consciousness. Unfortunately, this next step in the journey coincided with Dennis suffering a back injury. Despite this, Joe and Dennis pressed ahead with Clone-man over the next two or three months whilst Dennis was off work recovering from his back injury. This led to Clone-Man initially being credited to “Bedside Productions”. Within the team, Dennis’ focus was on core software, with Joe sorting out the hardware necessary for their development systems and providing some additional utilities. Dennis says that he saw porting PAC-MAN as “just a challenge to see how to copy an arcade video game onto Intellivision”

 

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Clone-Man - a Glimpse of Dennis and Joe’s homage to PAC-MAN

 

The resulting “Demonstration Program” was a pretty comprehensive recreation of the game, with a landscape version of the original maze, power pellets, bonus fruit, and sound effects. However, the algorithms that drive the movement of Blinky, Pinky, Inky and Clyde were not replicated and there are no intermissions. Overall, the game is clearly superior to the Atari 2600 version, but is not as polished as the Atarisoft version for the Intellivision, for example the sound effects are not replicated as accurately. As Joe says, Clone-Man “came out pretty good. Not good enough for commercial appeal, but good enough”. Dennis’ opinion is that “it would have been hard to tell it from Pac Man”, which is probably stretching things. However, with its more accurate maze, it clearly attempts to be more faithful to the arcade original than either the Atari 2600 or official Intellivision ports.

 

Throughout this period, Joe and Dennis continued to enhance their PlayCable test systems. The modified adapters were linked to their PDP-11 computers using an RS-232 serial connection, and ran enhanced firmware containing a debugger called CYBER. The pictures below show the results of Joe and Dennis’ alterations (see Section 8.3 of the PlayCable Technical Summary for more details).

 

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Joe and Dennis’ Development Kit PlayCable Receiver Board

 

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Joe and Dennis’ Development Kit PlayCable Digital Board

 

In addition to modifying the PlayCable adapters to support RS-232 communication, Joe added what he calls a “vector” board to their development Intellivision Master Components. These enabled breakpoint and single stepping features to be added to the CYBER debugger being developed by Dennis. A video showing CYBER being used to debug an Intellivision program can be seen here:

 

 

The modifications made to the PlayCables were pretty extensive, and together with Dennis’ CYBER debugger, they led to the early MAGUS-like ROM emulator turning into a system that had similar features to Mattel’s Blue Whale test harness. This can be seen in the following list of CYBER commands:

 

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CYBER Debugger Command Crib Sheet

 

Once Clone-Man was complete, Joe says he “did some checking with Jerrold management about our intentions of writing something for Mattel; they didn't have a problem so I went for it”. He used a Betamax video camcorder to record Clone-Man running on the Intellivision and sent the tape to Don Daglow at Mattel. At this point Joe says that “evidently, the crap hit the fan at Mattel”. Joe doesn’t really remember any fallout at Jerrold over Clone-Man, but the Mattel people were clearly “spinning in their seats”. Given Mattel’s paranoia over industrial secrecy, this was perhaps inevitable. Many phone conferences ensued over the next couple of months as Joe negotiated a deal with Mattel to write a game. This led to an agreement in December of 1982 that Technology Associates, the fledgling computer consulting company founded by Joe in 1981, would write a port of Bump N Jump for the Intellivision under contract to Mattel. Effectively, Technology Associates became a second-party developer for Intellivision, like APh. As might be expected, Mattel seems to have been concerned that Joe and Dennis could take their skills and knowledge to a competitor. However, Joe and Dennis are clear that this was never an option for them and, despite what is reported elsewhere, they did not threaten to do so. In fact, Jerrold was aware that Joe and Dennis had approached Mattel, and seems to have been supportive of their entrepreneurial streak, as they both continued in their day jobs. The reasons for Jerrold’s lack of concern over their game-writing endeavours are unclear, although Joe explains it like this, “We did not work on BNJ during our work hours at Jerrold for obvious reasons. Jerrold was aware of the situation and left us to it. At the time, we were pretty valuable employees... Besides, there was absolutely no negative karma, letting us do our own thing at the time. A benefit of working for a smaller company”. Regardless, like Clone-Man before, the Bump N Jump project was to be an extra-curricular activity for Joe and Dennis that occupied their evenings and weekends. What would have happened if a deal had not been struck? According to Joe and Dennis, they would have continued working for Jerrold at their regular day-jobs, and would have explored the Intellivision on their own time just for fun.

 

Having landed the contract to write Bump N Jump, and with the dust settling, Technology Associates purchased two new PDP-11 systems from Sigma Information Systems, complete with 8” floppy disks and enormous 20MB hard drives. These machines would be used to do the bulk of the subsequent Bump N Jump development. Up to this point, Joe and Dennis only had a single PlayCable development system to test Clone-Man. Joe took the opportunity to rectify this by building a second test harness to use while creating Bump N Jump, and the pair set to it.

 

In all, development of Bump N Jump took around six months of intensive work in the evenings and weekends. Joe suggests that “Dennis was, no question, the brains behind the code. While he worked on game play such as object generation, object interaction, scoring, etc. I was responsible for the entire background”. Dennis agrees, explaining that “Joe did the background and track work”, effectively being responsible for the accurate reproduction of the levels. To help with development, Mattel shipped an arcade version of Burnin’ Rubber (the international variant of Bump ‘N’ Jump) to Dennis' house. Once installed in the basement, Dennis' girlfriend's son played the game for hours and became an expert at it. Joe used his camcorder to record the teenager’s games for use in development. By watching the recordings back, over and over, ad nauseum, Joe was able to transcribe the levels of the arcade game using a level designer written by Dennis. Joe says, “The background of Bump ‘N’ Jump is basically a gigantic table of ‘cards’, with the presentation of those cards handled by Dennis’ level designer code”. As a consequence, the Intellivision port has a faithful reproduction of the playfield of the arcade version, including the track layout, bridges and other obstacles. Meanwhile, in addition to the core game mechanic, Dennis wrote more tools, including a music generator and an animation designer to support development.

 

As Bump N Jump took shape it became clear that the 8K of RAM within their PlayCables was not going to be enough to hold the full game. Sadly, the limits of their homebrew development kit had been exceeded. So, Joe “contacted Mattel to ask what was available to get past the 8K limit, and their answer was a board called the 16K Megas board". Mattel sent a couple of Megas (aka MAGUS) test harnesses for end-to-end play testing and Joe sorted out the hardware necessary to interface them to their PDP-11s. This he did by customising a Heathkit parallel interface board. Joe explains that during use “you had to tell the Megas board to 'freeze' the CPU from accessing the Megas ram, load the RAM, un-freeze the CPU and then tell the CPU where to start executing. Basically, it was a RAM-based burn and crash idea, but instead of burning an eprom or rom, you 'burned' the Megas RAM and it was pretty quick. A lot quicker than burning chips. The Megas wasn't really for troubleshooting/debugging but more an end-to-end play/test of the game you were working on”.

 

As was mentioned by Keith Robinson at Classic Game Fest in 2016, David Warhol acted as the liaison between Mattel and Technology Associates. Unfortunately, the relationship between the two organisations was not easy, as Joe observed, “I think the Mattel developers were definitely leery of us and certainly didn't voluntarily share anything on their own. If we had a particular question [that] needed answering they did answer but only the exact answer, nothing more, nothing less. We were still 'outsiders'”. Mattel’s attempts to limit the flow of information to Technology Associates can be seen as part of their ongoing attempts to hold their cards close and prevent third parties developing games for the Intellivision.

 

Joe and Dennis finished the core game of Bump N Jump at the end of May 1983 and shipped the source code containing two levels to Mattel HQ in Hawthorne. Once there, it entered the Intellivision QA process. A BSR review meeting in the first week of June highlighted that game play tuning was required. The most significant points raised were that the game required a greater sense of speed, with the enemy cars needing to be easier to bump and kill, but also requiring more personality and aggression to increase the intensity of the game. A number of developers requested the inclusion of an engine sound, to provide auditory feedback of the player’s speed. It was at this point that Mattel decided a change to the title screen was also required. The original received mixed reviews, with some confusion about whether it depicted a road or a mountain. Regardless, it was felt to be too similar to the introduction of Buzz Bombers and needed an update. The final animated titles were developed by Daisy Nguyen and seem to have been added sometime in early July. As always, there were also some bugs found that were subsequently fixed. Although Joe and Dennis don’t recall Mattel requesting much work after the code was shipped, a message from David Warhol suggests that the updates were split between Mattel and Technology Associates, with Mattel looking after graphical tweaks and Daisy’s title screen, while Joe and Dennis focused on game play tuning. It’s clear that not all Mattel’s suggestions were included, for example, music wasn’t added to Daisy’s title screen, and the requested engine sound isn’t present in the released version. The final game with its full set of levels was accepted for production by Dale Lynn and Traci Glauser on August 1st 1983 as can be seen in the QA report below.

 

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Mattel Bump N Jump QA Record

 

At around this time it normally took Mattel about three months to get from acceptance of the final code to a game hitting the stores. Roughly two months of this time was ROM production, with the last month typically being consumed with finalising printed materials, packaging the game and distribution. The advert below for Bump N Jump was run in the October and November issues of games magazines across the US, and according to The Video Game Update, the title was one of the last games Mattel released when it hit store shelves in November 1983.

 

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Bump N Jump Print Advertisement

 

Joe and Dennis are rightly proud of Bump N Jump and they feel that the title really pushed the capabilities of the hardware. The game play is very similar to the arcade, with the original levels and background music both faithfully reproduced. Unfortunately, interest in the Intellivision dwindled rapidly with the closure of Mattel Electronics at the start of 1984, and there seems to be very little about Bump N Jump in the press after its release. The Video Game Update did review Bump N Jump in their January 1984 issue, giving the title two and a half out of four stars for both graphics and gameplay, rating it as fair to good, but questioning the game’s depth, and therefore not recommending it.

 

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Video Game Update Bump N Jump Review

 

However, history has been rather kinder to Bump N Jump, the title is now consistently rated amongst the Intellivision’s best games. This includes the current generation of Intellivision gamers placing it in the top 10 Intellivision titles in 2014, and the top 15 games in 2019. Reviewers such as The Intellivision Library, Intv Funhouse and Video Game Critic all rate the game highly, noting the quality of both graphics and sound, and the accuracy of the conversion. Overwhelmingly, the prevailing wisdom is that Bump N Jump deserves a place in your Intellivision collection.

 

In late June 1983 Mattel Electronics announced the first round of redundancies that would mark the start of a death spiral for the division. Unsurprisingly given the timing of the completion of Bump N Jump development, Joe and Dennis didn’t receive offers of additional Intellivision work. With hindsight, the decision to continue to work for Jerrold whilst developing Bump N Jump on their own-time can be seen as an excellent one! Later, at the end of September David Warhol wrote to Joe and Dennis explaining the situation, and expressing the hope that more projects might be on the horizon with Mattel’s new focus on software; unfortunately, this future never materialised. Although they were initially unaware of the turmoil at Mattel, it was clear to both Joe and Dennis that they would always be considered outsiders at Hawthorne. In addition, Dennis explained that he enjoyed his work at Jerrold, and whilst writing Bump N Jump was profitable as a side-line, the money they made writing it wasn’t good enough to tempt the pair into giving up their day jobs. They also decided against pursuing opportunities with other games companies. Instead, they continued working for Jerrold and went back to just hacking for fun. Having grown tired of his lengthy commute to Hatboro, Joe left Jerrold in 1984 for a new role working for Omnidata (later Singer-Link Simulation) on power plant simulators, used to train control room engineers. However, Dennis continued with Jerrold, rising through the ranks to become Director of Project Management before retiring in the mid 2000s.

 

So there we go, the story of the development of Bump N Jump and the mythical PlayCable development system from the perspective of Joe and Dennis. Incredibly, their whole Intellivision adventure lasted less than 30 months. It would be great to get the recollections of Mattel people like Don Daglow and David Warhol, and the management at Jerrold to complete the picture. Hopefully one day.

 

One last thing before I go… A little birdy tells me that there is an Easter egg buried in Bump ‘N’ Jump that has gone undiscovered since the game’s release. Can the players and developers of the Intellivision Brotherhood find it? The challenge has been issued, just for kicks.

 

Once again, thanks to Joe and Dennis for giving their permission to share their story and for their help in putting it together.

Edited by decle
Tidy up formatting
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Nicely done.

 

If these guys had an Exec listing, that's more than what Mattel programmers had from what I understand.

 

So is Bumpnjump a 20fps Exec game like most Mattel cartridges.

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So, much for the 2 teenagers that hacked the Playcable. These guys were full grown engineers with a PDP at home. :)

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The old Intellivisionlives web site said "a couple of guys with a PC".  I guess Keith didn't know they worked for the company that developed the Playcable system with Mattel.  They say they didn't get paid much and had no intention of going to competitors.  Had Atari got a hold of them a year or two earlier, that might have been different.

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3 hours ago, mr_me said:

Nicely done.

 

If these guys had an Exec listing, that's more than what Mattel programmers had from what I understand.

 

So is Bumpnjump a 20fps Exec game like most Mattel cartridges.

Yes, Bump & Jump is using the Exec.  It's making Exec function calls and writes values to Exec memory right away.  If you poke a 7 at $104, it disables the sprite used for the water hazard warnings.  Poking a 3 there disables the opposing cars as well.

 

The level data is in $fxxx.  I'm working on reverse engineering it now.  Imagine a level editor in the future, joining Burgertime.

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20 hours ago, Intymike said:

So, much for the 2 teenagers that hacked the Playcable. These guys were full grown engineers with a PDP at home. :)

 

18 hours ago, mr_me said:

The old Intellivisionlives web site said "a couple of guys with a PC".  I guess Keith didn't know they worked for the company that developed the Playcable system with Mattel.  They say they didn't get paid much and had no intention of going to competitors.  Had Atari got a hold of them a year or two earlier, that might have been different.


Count me as another one one who is gobsmacked by the reality being so much more impressive than the myth.

 

Like others, I too got the impression from Keith's comments on the topic, that these were just a couple of kids who took their dad's PlayCable from the living room, hacked away at it to somehow hook it to their micro, reversed engineered the basics of the EXEC with it, and made a simple game.

 

It is fascinating to learn the whole story.  The fact that they were both CableTV engineers working at the company that produced the PlayCable itself, almost seems like cheating -- and yet ... somehow I am even more impressed.

 

This is truly one for the books -- a real-life Intellivision legend, and the yarn spun by @decle is as exciting and interesting as it is rich in technological details.  Great stuff!

 

Thank you for taking the time to follow up on this story, and for recounting it so thoroughly.  Also, thank you to Joe and Dennis for being so gracious with their memories and surviving assets of their saga.

 

   Cheers!

   dZ.


 

P.S. The technology review and demo of the CYBER is also very interesting, and offers yet another hint at how sophisticated development environments were back in the early days of software.  Thanks for doing it.

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First up, thanks for the kind feedback, it's much appreciated.  Now on to some specific points...

 

On 9/13/2021 at 2:04 PM, Intymike said:

So, much for the 2 teenagers that hacked the Playcable. These guys were full grown engineers with a PDP at home. :)

 

On 9/13/2021 at 3:42 PM, mr_me said:

The old Intellivisionlives web site said "a couple of guys with a PC"

 

On 9/14/2021 at 10:38 AM, DZ-Jay said:

just a couple of kids who took their dad's PlayCable from the living room, hacked away at it to somehow hook it to their micro, reversed engineered the basics of the EXEC with it, and made a simple game.

 

Yup, Joe and Dennis were, and are, both professional engineers, not spotty teenage hackers who wrote "Hello World" for the Intellivision.  This is perhaps part of the reason Mattel took them seriously.  Personally, I wouldn't describe what they did as reverse engineering the PlayCable, because they were part of the team developing it.  However, they did use the skills and tools at their disposal to repurpose the PlayCable adapter in an innovative way, and put together a pretty sophisticated development kit using it, kudos to them. :thumbsup:

 

On 9/13/2021 at 3:42 PM, mr_me said:

I guess Keith didn't know they worked for the company that developed the Playcable system with Mattel.

Sadly, Keith does seem to have been aware of who Joe and Dennis are, as can be seen here :(  I suspect that any concerns Mattel had over others repeating what Joe and Dennis did were massively overblown.  To use the PlayCable to construct a development kit required access to a pre-production Jerrold model. These were used for internal development work, and perhaps for the early field trials.  As such, I believe they were probably limited in number and I expect Jerrold restricted access to them.  It would not be possible to use a regular PlayCable branded adapter to create a devkit in this way because all its digital logic was consolidated onto a single chip.

 

On 9/13/2021 at 5:17 PM, Tempest said:

So on that list of titles, what is #49 'Pick a Doodle'?

This list came with a PlayCable adapter that a lucky collector bought from a retro shop in NJ.  We are pretty confident that it was one of the modified PlayTape adapters previously owned by a Jerrold engineer.  Unfortunately no audio cassettes were with the PlayCable, and therefore, they are presumed lost.

 

The numbers on the list are believed to be the tape counter value on the cassette player at the start of each game.  So the list shows the contents of either four single sided PlayTape audio cassettes, or possibly two tapes with recordings on both sides.  Notice how most of the 4K games on the list are separated by a count of 6 or 7 , but the larger 6K game Sub Hunt has a length of 9.

 

Pick-a-Doodle is a little animation program originally written by Dennis in 1981.  It allows non-programmers to put together up to 20 frames of background cards and play them like a flick-book accompanied by background music.  Here's a short video of it in action...

 

 

...I forgot to mention in the video that Pick-A-Doodle was meant to be run on the PlayCable devkit.  So it stores the animation frames in PlayCable RAM, and this data can be downloaded to the developer's computer once it is complete, so it can be played back later or potentially be incorporated into another program.

 

I am working with Joe and Dennis to recover data from one of their old PDP-11 systems, and as you can see we have had some success.  I hope that we might be able to share videos of more of this stuff in due course.  We can already see that it contains some cool bits and pieces, especially for dweebs like me. :dunce:

 

 

Edited by decle
Additional note of downloading Pick-a-Doodle animations
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Ahh, so Keith did know they worked for the company that developed Playcable; this wasn't mentioned on his website.  He didn't say they reverse engineered Intellivision programming but did say they demonstrated they could program Intellivision games well.  Now we know why.

 

I think there was always a bit of friction with outside developers like APh.  And by that time both Mattel and APh had lost talent to Activision, Imagic, Atari, offering royalty deals and more money.  But these two guys seemed to have negotiated a very modest deal with Mattel.

 

So one of these guys has their old PDP-11 compatible computer, and it still works?

Edited by mr_me

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as a kid the one Easter egg, if it could be called that, I found was the road off the edge of the screen. You could jump, land at on a small invisible road off screen and drive the whole level on it with no obstacles, but you'd have to time the end of the level  and jump back onto the normal road or your car would crash when the CPU took over control and centers your car onscreen.

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On 9/17/2021 at 9:42 PM, mr_me said:

I think there was always a bit of friction with outside developers like APh.

That does seem to be a fair description.

On 9/17/2021 at 9:42 PM, mr_me said:

And by that time both Mattel and APh had lost talent to Activision, Imagic, Atari, offering royalty deals and more money.

Indeed, which should have meant that Mattel was less concerned about the risk of Joe and Dennis going elsewhere than Keith portrayed.  They were only two amongst many.

 

<SpeculativeCity>I wonder whether Jerrold's initial expectation that they would write exclusive games for PlayCable, the fact that this never came to pass, their laissez-fair attitude toward Joe and Dennis' extra-curricular activities, and Mattel's reaction when the pair rocked up with Clone-Man are somehow linked</SpeculativeCity>.  We'll probably never know.

On 9/17/2021 at 9:42 PM, mr_me said:

So one of these guys has their old PDP-11 compatible computer, and it still works?

That is correct. :party:

 

On 9/20/2021 at 10:28 AM, vectrex said:

as a kid the one Easter egg, if it could be called that, I found was the road off the edge of the screen.

Unfortunately that is a bug that was missed during QA, not the Easter egg.  Keep looking... :)

 

On 9/13/2021 at 9:40 PM, Zendocon said:

With what I figured out so far, I might be able to create a level editor.

Well, would you be interested in seeing the level / track editor that Dennis wrote for Joe to use?  If so, it was on one of the floppy disks and we've managed to get it working...

 

 

...Dennis also wrote a tool to help develop the animated cars which was on another disk...

 

 

...and here are some of the early player car graphics that Joe and Dennis put together for Bump N Jump (the gif shows the MOBs both linked / overlaid and split)...

 

carPlayer.gif

 

...I know it's authentic to the arcade game, but I never understood the "wobbly wheels" aesthetic, I much prefer the rotating effect Joe and Dennis created here.  Anyway, next we have what I suspect are some enemy cars...

 

car01.gif

 

car02.gif

 

car03.gif

 

car04.gif

 

car05.gif

 

car06.gif

Edited by decle
Crappy Invision wysiwyg BS
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27 minutes ago, decle said:

Indeed, which should have meant that Mattel was less concerned about the risk of Joe and Dennis going elsewhere than Keith portrayed.  They were only two amongst many.

 

<SpeculativeCity>I wonder whether Jerrold's initial expectation that they would write exclusive games for PlayCable, the fact that this never came to pass, their laissez-fair attitude toward Joe and Dennis' extra-curricular activities, and Mattel's reaction when the pair rocked up with Clone-Man are somehow linked</SpeculativeCity>.  We'll probably never know.

I think it's clear that Keith assumed, incorrectly, that they were shopping their services around.

 

Regarding Jerrold getting into game development, if their idea was to convert popular arcade games, that wasn't going to happen without licenses.  They'd have to come up with game ideas, which isn't easy.  The idea might have been about what Dennis might do after developing the Playcable firmware.  What would the business case for Jerrold providing games to Playcable have been.  Their parent company like Mattel shares the subscription revenue.  It would have to be a business decision coming from GI.

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It seems to be these 2 engineers knew early on that 8K wasn't going to cut it for the Play Cable. 

So either Intellivision / Mattel was a little afraid of the possible competition or a little short sighted.

 

I think it would have been great for Mattel if Jerrold also created content.

It would make the subscription service more appealing to subscribers and would have pushed more intellivision units.

 

I would imagine they would have pushed for 16K and not the 24K+ needed for Voice games.

 

I think I read that the service used to much bandwidth.  I would think if you are getting $10-$15 a month per subscriber, for a single channel slot, IF it took an entire channel's bandwidth.  

It would come down to number of subscribers.  HBO was like $5 a month back then.  Could you get 1/2 to a 3rd the number of subscribers?  Then this would be a non issue.

 

I think it would be a funny sight to see an Intellivision -> Intellivioce -> PlayCable   Playing B-17  Or toss in the ECS and WSMLB playing!

 

Shit, at the time of the ECS, I wonder how hard it would have been to add a modem-ish device inside the ECS to add PlayCable capability?

 

And we would have had a usable amount of ram in the thing!  Ah, what could have been.

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On 9/25/2021 at 10:15 PM, 1980gamer said:

Shit, at the time of the ECS, I wonder how hard it would have been to add a modem-ish device inside the ECS to add PlayCable capability?

 

And we would have had a usable amount of ram in the thing!  Ah, what could have been.

Wasn't that being planned at the time?  Some ECS units have been found to have some kind of RAM expansion slot in them, and some IntelliVoice units had a slot as well for a wireless controller interface.  Somewhere along the way, I'm pretty sure there was talk of a modem.  Probably would have been only 300 baud, but who would ever need more than that?

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I don't think I've seen an ECS modem option mentioned in any catalogs.  As far as downloading games, ECS ram is only eight bit and can't run Intellivision games.  The 1983 dealer catalog mentions an Aquarius modem and the original Keyboard Component intended to have a modem for online services.  Those system had a more useable text resolution for online services.

 

Space Spartans is an 8K cartridge and would fit on playcable.  The intellivoice audio pin is apparently grounded in Playcable causing it's audio to be cancelled.  Sounds like a design mistake somewhere.  The other intellivoice cartridges are 12k.  I thought there was something about the possibility of larger games on Playcable by downloading games in segments.  Games would have to be written for that.  If Playcable and Intellivision were successful beyond 1983, they'd probably just upgrade the units with more ram.  Cable companies found success with MTV, movie channels, pay tv, etc, to invest more on the TV side.

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The possibility of a modem was never announced to consumers that I know of, as you say.  Where I saw it was in some kind of concept sketch with the Intellivision II family of peripherals, which included the Music Synthesizer and Computer Keyboard (which looked much better than the final product).  All right up there with that fake "IntelliVoice II" unit.

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Wasn't there a plan to release an updated BASIC cartridge and expanded RAM for the ECS?  That wouldn't help with the size of the game code, though.

Edited by DZ-Jay

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An updated ECS Basic and ram expansion was in the dealer catalog.  That would have been cancelled, with all other hardware projects in summer 1983.

 

If Playcable buggers up the audio input used by intellivoice, wouldn't it cause the same problem if it were to run ECS programs using the second sound chip, or, if it were left plugged into a Keyboard Component, audio coming from a cassette tape.

Edited by mr_me

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7 hours ago, mr_me said:

I don't think I've seen an ECS modem option mentioned in any catalogs.  As far as downloading games, ECS ram is only eight bit and can't run Intellivision games.  The 1983 dealer catalog mentions an Aquarius modem and the original Keyboard Component intended to have a modem for online services.  Those system had a more useable text resolution for online services.

 

Space Spartans is an 8K cartridge and would fit on playcable.  The intellivoice audio pin is apparently grounded in Playcable causing it's audio to be cancelled.  Sounds like a design mistake somewhere.  The other intellivoice cartridges are 12k.  I thought there was something about the possibility of larger games on Playcable by downloading games in segments.  Games would have to be written for that.  If Playcable and Intellivision were successful beyond 1983, they'd probably just upgrade the units with more ram.  Cable companies found success with MTV, movie channels, pay tv, etc, to invest more on the TV side.

I wasn't saying the ECS as released.  IF they had any plans for the PlayCable.. Clearly they pulled the plug as it rolled out.

They could have easily used 16bit wide ram.

They could easily have added the proper Coax connector and UART to read the stream. 

 

Believe me, if the cable companies were making a nickle off play cable, they would find the bandwidth. 

Plus, I am certain they could easily piggyback this tiny stream to any channel.  Also, back in this time, most programming was mono, using the stereo audio channel I think (right?) been to long since electronics school...

they could put the stream their.  This wasn't anything beyond it was KILLED.

 

 

 

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With Playcable, customers didn't buy the peripheral, it was part of the subscription.  Having people have to buy an expensive peripheral as well as an expensive master component would limit it's reach.  Playcable continued until the end, it outlasted Mattel from what I understand.

 

Playcable was an investment for cable operators, so was supporting a constantly increasing number of television channels.  The future of Intellivision was effectively dead in mid 1983.   They could have adapted it to another system but the timing was bad.

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I get it.  I am saying, if it was a viable platform.  That is Mattel and Jerrold making money.

It would have been pretty easy to add playcable functionality into the ecs.  Maybe making that a valid product?  Or heaven forbid, another way to compete with Mattel.  LOL

 

My thinking is with an ECS installed base, customer could force cable providers into adding the service.

In areas with playcable, either the monthly rate could be reduced and/or a larger % goes to mattel as they had the hardware outlay instead of Jerrold.

 

This is crazy to even talk about.  But looking back, things could have been very different.  Can you imagine if the ECS truly made the Intellivision the Intellivision III.

Better, faster games with more objects on screen etc.

 

As far as the "crash" goes.  I didn't have a single friend or acquaintance that didn't continue to play and buy games throughout the early to mid eighties.  Then we all got NES's

 

I actually never used my NES.  1 sister did.  I have that dam Mario theme etched in my head.

 

I was still buying Super Pro stuff and Commodore 64 games.  I remember waiting for NEW games for intellivision in the catalog.  Hover Force!  How awesome was that!

I got my fiend Tower of Doom for his Birthday and Slam Dunk for Christmas.  knowing we would be swapping games all the time anyway!  LOL

 

Still hoping for F1 Frenzy   Super Pro Auto Racing  or some other great name for it.  We need David to get cracking!  New tracks, faster cars etc.

We kinda got that with Motocross.  Track Building at least.  Would be cool to save tracks.

 

Okay, sorry for derailing this topic.  It is really great look at actual history.  Not my crazy what if's

 

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