Defender Conversion for the CoCo 3 – Part 6 – Three out of Three attract Screens are converted

Today I completed converting the Defender Arcade code to play through all three attract modes.  The last one was definitely the hardest as it contains the sprites moving around the screen.  I also had to convert how Defender draws the planet surface and get the scanner working.  Unfortunately the CoCo 3 doesn’t have enough rows on the screen to match the height of Defender.  So I decided to leave the playfield area exactly the same as the arcade version so the play and feel will be the exact same on the CoCo 3.  To make room for the scanner at the top of the screen I had to reduce the height of it by half.  This should still give me enough room for the player’s reserve ships, smart bombs and score to fit.  Click here to see the video of the conversion so far.

Screen Shot 2018-02-07 at 7.34.53 PM

Now I can start on the actual game play, hopefully it won’t be so bad since most of the graphics conversion is done and it’s a matter of adding the controls and all the game logic.


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9 Responses to Defender Conversion for the CoCo 3 – Part 6 – Three out of Three attract Screens are converted

  1. Ted KC9LKE says:

    Excellent work Glen!

  2. Brian P says:

    Glenn, Mate I hope to see this port finished as we are so keen to play Defender on the coco 3

    • nowhereman999 says:

      Hi Brian, thanks for the post. It’s nice to know that others would like to see me complete this conversion. Lately though I haven’t been doing much with the CoCo but the Defender conversion is still in the back of my mind and hopefully one day I’ll get back to it and find the bugs that stop it from working properly. Cheers, Glen

  3. briza1 says:

    Well you are becoming the Port king on the coco 3 as Socks passed on the banner too anyone keen on doing Ports 🙂

    • nowhereman999 says:

      Hi Briza1,

      I’m not exactly sure what your comment means, but understanding these old games from a hardware and mostly software level has always been a big interest of mine as does emulation of many old arcade games. So doing these translations/conversions for our wonderful old CoCo has taught me a lot and is a lot of fun. But when things don’t work it’s such a big pain in the ass to squash the bugs. That is never fun!

      I thought I’d let you know that I haven’t gotten back to fighting with my Defender conversion but I still plan to at some point. But lately I have been going through my Space Invaders transcode to make it work on the CoCo without having to rotate your monitor. It’s always bugged me that the finished game worked but wasn’t “really” playable as a CoCo game as nobody wants to rotate their monitor to play a game. The code i’m working on is currently for the CoCo 3 but in the back of my mind I’m thinking I might be able to get the Space Invaders transcode to work on a 32k/64k CoCo 1/2.

      I’m having fun with it though, but there is way more to it then a simple rewrite of the sprites! Everything has to change, including the detection of collisions which turned out to be way more simple if you rotate the monitor. Maybe I should put up a blog post about my progress on space invaders. Doubtful though as at this point I’m just trying to keep it fun again and not go crazy deep into the code/rabbit hole…

      Thanks for your comment!


  4. briza1 says:

    Mate, we like any blogs on games being worked on, And we really enjoy reading your blogs as you describe perfectly what is happening during your port journey.. Space Invaders sounds interesting as it is another well known Classic and getting a coco 1,2 version as well as a coco 3 will excite the masses for sure!!!

    If keeping your Invaders Port too yourself and not blogging it will help you keep the fun factor I say do what makes you happy, we are all happy just knowing you are still around and starting to enjoy coco coding again. And No rush on finishing any as we need you to stay happy and not feeling like it is just work and not fun…



    • nowhereman999 says:

      Hi Briza1,

      Your comments are nice to read, I appreciate you taking the time to write. I definitely want to keep the CoCo hobby fun without any pressure. That’s my top priority at this time, hopefully it will lead to some progress on these old games.


  5. Luis Fernández luiscoco says:

    Muy buena labor desde Venezuela y España seguimos tus pasos, impresionantes detalles de velocidad superior del 6809 y recomiendo intentes versiones del Hitachi 6309.
    Yo ayude al port de the hobbit para coco y dragón hecho por pser1 en y worldofdragon

    • nowhereman999 says:

      Thanks for the comment, I prefer to get Defender working on my original CoCo 3 with a 6809. Kind of like to say “this could have been done for the CoCo 3 with original hardware back in the 80’s.” – One of these days I’ll get back to working on this game.

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