Jump to content
Ed Fries

The First Color Arcade Video Game?

Recommended Posts

I read this in its entirety earlier today. So fantastic, I'm glad you persevered! Thank you for sharing your experience!

 

..Al

  • Like 1

Share this post


Link to post
Share on other sites

I read the entire Wordpress also.

Extremely fascinating and enjoyable, thanks!

Even Nolan Bushnell was not sure, wow!

 

My "guess" would have been 6 years later!

(Probably most people saw Galaxian when it came as a color screen and not black and white with a color overlay.)

I was 12 in 1979 and I am still finding games from 1984 back that I never saw or played!

  • Like 1

Share this post


Link to post
Share on other sites
Thanks for the interesting write up and the motivation to carry on with my own repair project of a somewhat obscure (ca. '76, but historically meaningless) machine.

  • Like 1

Share this post


Link to post
Share on other sites

Wow, sweet article you wrote up! I would've never guessed that Color Gotcha was a thing - I never even heard much about Gotcha in the first place so it wouldn't have been a guess I'd ever make. I love reading these repair projects, and that sure looks like a heck of a project - thanks for posting that article on here.

  • Like 1

Share this post


Link to post
Share on other sites

Thanks! I just read it too. I love this stuff!!

 

By the way, an Open Collector (or Open Drain in FET terms) output is one that's missing the pull-up transistor. Normally, logic chips have a transistor to clamp the output to ground and another one to clamp it to the Vdd rail. By eliminating the 2nd one, the output simply becomes disconnected (or floats) when the output is "high". This can be handy in several instances, but the primary one is the wired-AND configuration. Normally, outputs cannot be combined but you can put many open collector outputs on a single trace with a pull-up resistor (of several Kohms or so, depending on your rise-time requirements) and that signal will be high as long as none of the outputs are low (clamped to ground). This eliminates the need for additional ICs with enough inputs to compare all those output pins.

  • Like 1

Share this post


Link to post
Share on other sites

Awesome!

 

Your bit about the counters and X and Y locations is somewhat true for the 2600 as well. If you check the disassembly for Combat you'll see RAM allocated for TankY0, TankY1, MissileY0 and MissileY1 but nothing for the X location. Instead, it uses RESPx to set the initial positions of the tanks at the start of each match, then uses HMOVE to adjust their X locations over successive frames.

  • Like 1

Share this post


Link to post
Share on other sites

Awesome!

 

Your bit about the counters and X and Y locations is somewhat true for the 2600 as well. If you check the disassembly for Combat you'll see RAM allocated for TankY0, TankY1, MissileY0 and MissileY1 but nothing for the X location. Instead, it uses RESPx to set the initial positions of the tanks at the start of each match, then uses HMOVE to adjust their X locations over successive frames.

 

Yeah, I think you are exactly right. The crazy RESPx, HMxx stuff must be a direct descendant of the slipping counter way of thinking about things.

Share this post


Link to post
Share on other sites

 

Yeah, I think you are exactly right. The crazy RESPx, HMxx stuff must be a direct descendant of the slipping counter way of thinking about things.

 

Yup, it was designed similar to how Cyan was already doing that stuff in coin (Cyan was doing most of the protos and proof of concepts for coin and then they'd be sent down to Atari to be put in production format). Not a huge leap from how things were already being done then when creating versions of all those earl and mid 70s coins for it then.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...