BigO Posted November 12, 2015 Share Posted November 12, 2015 (edited) Recently, several Atari 2600 titles have been hacked to support true trackball control. Not wanting to be left out, I dug out an old, dead Wico trackball. It was designed for the 2600, but it was designed to emulate a joystick. Fortunately, it was also dead. No output. The microcontroller was kaput. The controller employs the common style, quadrature optical encoder. Those encoders were still working. Not wanting to ignore the craze, I decided to hack my Wico into a "true" trackball. (I was already familiar with Gray code, quadrature encoding, etc. from working with industrial controls so I knew what I was looking for.) The hack is relatively simple. My implementation used a 28 pin DIP socket, a HCF4069 inverting buffer, wire, and soldering equipment. I used an inverting buffer simply because I had one sitting around available (for, like, 20 years). Here's the wiring that I did to adapt the 14 pin buffer to the 28 pin socket native to the controller. I chose to wire the buffer into a separate 28 pin socket and plug it into the controllers original socket. Orig Cons Socket 4069 4069 Plug Pin Pin Fnct I/O Axis Pin ------ ---- ---- --- ---- ---- 9 3 2A I Va 12 4 2Y O Va 3 ---------------------------------- 8 1 1A I Vb 13 2 1Y O Vb 4 ---------------------------------- 10 13 6A I Ha 21 12 6Y O Ha 2 ---------------------------------- 11 11 5A I Hb 20 10 5Y O Hb 1 ---------------------------------- 3 14 +5v 6 7 GND ---------------------------------- 5 NC 6 NC 8 NC 9 NC Conceptually: The two optical sensors on the vertical axis of the controller feed into pins 8 and 9 of the 28 pin socket Pins 12 and 13 of the 28 pin socket are the outputs, feeding the vertical axis signals to the game console pins 3 and 4 So, the signals go into pins 8,9 and out pins 13,12 respectively The job of the buffer chip stuck in between is just to connect the inputs to the outputs (providing a necessary signal boost along the way) The same is true of the horizontal axis using pins feeding into the socket on pins 10,11 feeding out on pins 21,20 respectively. Again, buffer channels are just sitting in between connecting the inputs to the outputs Note: A lot of my choices were arbitrary and/or convenient. You can use any four of the six channels available in the typical hex buffer. If you choose to use a non-inverting buffer, you'll need to switch the polarity of the outputs, i.e. where I said pins 8,9 feed to 13,12 respectively, you'd need to 8,9 to feed to 12,13 and you'd need 10,11 to feed through to 12,13 20,21 respectively instead of 13,12 21,20. Here's my implementation, plugged into the board from the controller. The blue part is the socket I built it in. It's plugged into the original black socket. Clearly, the mechanical adaptation could be done more cleanly with a custom pc board and header pins. But, it works as is for a one-off. [edit 5/25/17: corrected alternate configuration pinout text] Edited May 26, 2017 by BigO 5 Quote Link to comment Share on other sites More sharing options...
Omega-TI Posted November 12, 2015 Share Posted November 12, 2015 Now that you've done the inside... why not the outside? Here is my Wico : BEFORE VIEW AFTER VIEW 1 Quote Link to comment Share on other sites More sharing options...
BigO Posted November 12, 2015 Author Share Posted November 12, 2015 Nice work. Not being so pretty on the outside myself, I'm good with the banged up, aged appearance of my trackball. We sorta coordinate that way. 2 Quote Link to comment Share on other sites More sharing options...
Lynxpro Posted November 15, 2015 Share Posted November 15, 2015 This project deserves its own website. Now with some modding, you could add a second fire button and make it compatible with the 7800. Or, perhaps consult with Dan Kramer so you could make it a 3-button model compatible with Atari's in-house A8 3 Base Missile Command. Quote Link to comment Share on other sites More sharing options...
Omegamatrix Posted November 15, 2015 Share Posted November 15, 2015 I have just added a link to this thread to the first post of the track ball thread. It seemed appropriate. Good work, BigO!! Quote Link to comment Share on other sites More sharing options...
BigO Posted November 16, 2015 Author Share Posted November 16, 2015 (edited) This project deserves its own website. Now with some modding, you could add a second fire button and make it compatible with the 7800. Or, perhaps consult with Dan Kramer so you could make it a 3-button model compatible with Atari's in-house A8 3 Base Missile Command. Thanks. With respect to supporting both fire buttons, 7800 compatibility is pretty near the top of the list for another little project I'm working on. (Hints left elsewhere.) I read about that 3 button thing once. I need to go back and look at how Mr. Kramer added that 3rd button. I might be able to do something with that. I'm not a huge fan of just hacking extra buttons onto stuff. It has to look right when I'm done, or I'd rather just build a full custom controller. Edited November 16, 2015 by BigO 1 Quote Link to comment Share on other sites More sharing options...
Lynxpro Posted November 16, 2015 Share Posted November 16, 2015 Thanks. With respect to supporting both fire buttons, 7800 compatibility is pretty near the top of the list for another little project I'm working on. (Hints left elsewhere.) I read about that 3 button thing once. I need to go back and look at how Mr. Kramer added that 3rd button. I might be able to do something with that. I'm not a huge fan of just hacking extra buttons onto stuff. It has to look right when I'm done, or I'd rather just build a full custom controller. If you are on Facebook and a member of the Trak-Bombers group, you can see the pics of Dan's custom 3 button Trak-Ball controller: https://www.facebook.com/photo.php?fbid=461419977357322&set=p.461419977357322&type=3 Here's what Dan had to say about the design of this custom Trak-Ball: "It's essentially the same circuitry as a CX22 in Trak-Ball mode that has a cable using its paddle lines (pins 5 & 9, I think) for the left & right fire buttons. Pressing one of the outer buttons grounds the paddle line to Count 0, so it is read as an active low. Anybody can build their own with the right cable and two more switches. I think the 2600 keyboard has the right cable with all wires present. Prototype time- go head on! This is a DIY project and likely will never see production. Thanks for the compliment on TBMC, and thanks to Rob Zdybel for writing the program! Shown: my DK 3B MC & TB at Atari Party 2015 May 2." Wait, I've found pics that aren't hosted on Facebook… on Bill Kendrick's site with pics of the 2015 Davis Atari Party: http://www.newbreedsoftware.com/atariparty/2015/photos/mm/10.jpg That's Dan's custom Trak-Ball from the Atari days. As his comment mentioned, Rob Zdybel wrote 3-Base Missile Command for Atari 8-bit for all the Atari staff to play in-house. What's not mentioned is Mr. Zdybel would customize each disk by entering the person's name in the game itself. Dan has the only remaining copy in existence after Mr. Zdybel's house caught fire [if I recall correctly]. The button layout is very natural and comfortable. The game is awesome and it cheats! http://www.newbreedsoftware.com/atariparty/2015/photos/rmm/atariparty2015-9.jpg Another pic of it. http://www.newbreedsoftware.com/atariparty/2015/photos/mw/dan_kramer_mike_albaugh.jpg On Dan Kramer's right is Mike Albaugh of Atari Coin/Atari Games who made the arcade Trak-Balls. http://www.newbreedsoftware.com/atariparty/2015/photos/mm/4.jpg Dan, Keithen Hayenga [programmed 5200 Tempest amongst others], and Jerry Jessop. All 3 have now been interviewed by Antic Podcast. http://www.newbreedsoftware.com/atariparty/2015/photos/bk/31.jpg Dan's 5200 Paddle built in Atari's lab from one of the first 5200 joysticks [the bottom keypad buttons have "Atari" written on them instead of * and #]. Main page: http://www.newbreedsoftware.com/atariparty/2015/photos/ Quote Link to comment Share on other sites More sharing options...
BigO Posted November 17, 2015 Author Share Posted November 17, 2015 I just remembered that when I rebuilt my Wico the first time, it had a bad cable. The one I replaced it with has all 9 pins. So, if somebody does come up with a game needing a 3 button, 9 pin controller, I might add buttons to that one. Quote Link to comment Share on other sites More sharing options...
dancroteau41@gmail.com Posted March 22, 2022 Share Posted March 22, 2022 in hopes to make me a chip set to plug in to my old 2600 trackball same one just not able to do this my self ive tried will compensate what ever is fair no rush just would like to know if this is posable???? please!!!! Quote Link to comment Share on other sites More sharing options...
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