antron Posted February 15, 2004 Share Posted February 15, 2004 Does anyone know why my games are displaying so poorly when I run them from Pixels Past's circuit boards for the 2600? It looks like the playfield luminescence register has random data in it (that changes when I turn the paddles!). Is this noise? Thanks anyone. Quote Link to comment Share on other sites More sharing options...
+Mitch Posted February 15, 2004 Share Posted February 15, 2004 Does anyone know why games are displaying so poorly when run from Pixels Past's PCBs? It looks like the playfield luminescence registers have random data in them (that changes when I turn the paddles!). Is this noise? Thanks anyone. It sounds like RF interference. Do you have them in a cart shell? That will help cut down on the interference. Mitch Quote Link to comment Share on other sites More sharing options...
antron Posted February 15, 2004 Author Share Posted February 15, 2004 I took an old retail cart apart, removed the metal shielding, and played it (just pbc and chip). It does not do this at all. I will put the Pixels Past PCB in the old case, but I don't expect it to help much. EDIT: It didn't Thanks for the reply. Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted February 15, 2004 Share Posted February 15, 2004 Maybe the PCBs need a little more power and your power is getting weak. Quote Link to comment Share on other sites More sharing options...
antron Posted February 15, 2004 Author Share Posted February 15, 2004 So that could be a problem with the voltage regulator? Also Thomas: Do these products support Thrust+ ? All I get is purple lines. I plan on buying Platinum Edition with the foot pedals, but for now I want to play the first version. It rocks on an emulator. Thanks. Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted February 15, 2004 Share Posted February 15, 2004 So that would be a problem with the voltage regulator? You better ask some hardware experts. I was just speculating as your problems sounded familiar. Also Thomas: Do these products support Thrust+ ? All I get is purple lines. AFAIK Thrust+ is made from Pixel Past's PCBs, so I suppose they should work. Maybe it is the same problem as above, just increased since Thrust is 16K. But again, you better ask AA or Joe Grand etc. Quote Link to comment Share on other sites More sharing options...
joesmooth Posted February 15, 2004 Share Posted February 15, 2004 The Pixels Past PCBs will not introduce any additional noise into the system. The speeds are low, the traces have been kept as short as possible, and all other proper PCB design practices have been done. We've sold thousands of the 2k/4k and Bankswitch 2600 PCBs with no reports of inconsistencies or problems. It could be a problem with the EPROM you are using, improper soldering/cold solder joints on your PCB, connection problems with your connector, power supply issues (are you using the proper 2600 power supply that provides the right amount of current, or are you using a third-party knockoff?) AtariAge uses Pixels Past boards exclusively to sell their games. The bankswitch board supports Thrust+, as that is what AA uses. Hope that helps, Joe Quote Link to comment Share on other sites More sharing options...
antron Posted February 15, 2004 Author Share Posted February 15, 2004 I am using a radio shack 9V 1.5A AC-DC converter. No problems with real carts. I am using the EPROMS AA sold me (and didn't, same problem). I am having the same problem with both a 2/4K and a 8/16/32 PCB. I purchased the PCBs pre-assembled. I will try them on a friend's Atari. If they the same problem I will post some pictures. I did a composite video mod on the 2600 once, but I removed it due to dissatisfaction. I could have damaged the Stella chip in some subtle way. Thank you everyone for the help. Quote Link to comment Share on other sites More sharing options...
joesmooth Posted February 15, 2004 Share Posted February 15, 2004 If you purchased the boards assembled from AA, they have been fully tested by the fine folks over there. Since this is indeed happening on both boards you have purchased (which are completely separate designs), I suspect the problem is NOT with the circuit boards or components on the boards. I would definetely try them on another system and see if the problem is recreated. I suspect it will not be. Please let us know! Joe Quote Link to comment Share on other sites More sharing options...
Albert Posted February 15, 2004 Share Posted February 15, 2004 Hello, I have personally built over 1,000 cartridges using the Pixels Past PCBs, and every game gets tested before I send the out. I haven't noticed any abnormal RF interference compared to regular Atari 2600 carts. I get a pretty good pictures on my television when using a coaxial f-type adapter, which bypasses a switchbox. All the games actually get tested twice, once after the board is built (before it's placed in a cartridge housing) and then again after the cart has been fully assembled. While I haven't been paying extremely close attention, I don't recall there being any difference in picture quality between the two states. Any pre-assembled boards with sockets are tested beforehand to make sure they work. Pre-assembled boards that just have the logic chips and discrete components cannot be tested in this fashion, but they are visually inspected to make sure there are no obvious problems (such as solder bridges between joints). I'd be glad to take a look at the boards if you want to send them back to us. ..Al Quote Link to comment Share on other sites More sharing options...
antron Posted February 16, 2004 Author Share Posted February 16, 2004 Well, I am getting the same results with another 2600. He also has a third party power supply. Bypassing the switch box has no effect. Quote Link to comment Share on other sites More sharing options...
joesmooth Posted February 16, 2004 Share Posted February 16, 2004 Have you ensured that the ROM you programmed into the EPROM is fully functional? And have you verified that the EPROM was programmed properly? Joe Quote Link to comment Share on other sites More sharing options...
antron Posted February 16, 2004 Author Share Posted February 16, 2004 They have been verifying okay, but to be sure I just dumped one to a file and it ran fine on an emulator. As far as my Trust problems, I now see that I cannot run any games larger than 8K. But, if I mirror smaller games to fill up a 16K or 32K EPROM they run (but with the same distortion). I have been confused by the fact that I must mirror 2K roms to 4K to get them to run on 2732. I tried on one half, then the other, but it only runs when on both halves. Is that normal? Anthony Quote Link to comment Share on other sites More sharing options...
CPUWIZ Posted February 16, 2004 Share Posted February 16, 2004 I have been confused by the fact that I must mirror 2K roms to 4K to get them to run on 2732. I tried on one half, then the other, but it only runs when on both halves. Is that normal?Anthony Yes, it's normal, the 2600 looks for the reset vector at the end of the EPROM address space. Quote Link to comment Share on other sites More sharing options...
joesmooth Posted February 16, 2004 Share Posted February 16, 2004 If you purchased a bankswitch board with the 8K PLD, it won't work with larger ROM images, as the PLD is programmed with specific bankswitch routines (F8, as opposed to F6 or F4). See the manual that was included with the board. Joe Quote Link to comment Share on other sites More sharing options...
antron Posted February 16, 2004 Author Share Posted February 16, 2004 If you purchased a bankswitch board with the 8K PLD, it won't work with larger ROM images, as the PLD is programmed with specific bankswitch routines (F8, as opposed to F6 or F4). See the manual that was included with the board. Joe Ohhhhhhh, I had my wife get me this stuff for christmas, and I didn't realize that. Thanks for clearing that up. I must have the 8k, I see now that it is the default on the AA order form. Thanks. Yes, it's normal, the 2600 looks for the reset vector at the end of the EPROM address space. Thank you too CPUWIZ. I am sure I will learn a lot more about that when I begin making my game:) Anthony Quote Link to comment Share on other sites More sharing options...
antron Posted February 16, 2004 Author Share Posted February 16, 2004 This the distortion on Super Breakout. It is more dramatic on other games with more color. I am showing this one because I have a real cart to compare it against. I tried it running straight to the TV, and by letting my VCR convert it to composite. Also on channel 2 and 3. Same results each time. My Sony Vega does it too. Quote Link to comment Share on other sites More sharing options...
antron Posted February 17, 2004 Author Share Posted February 17, 2004 I just want to say that although there are definitely some electrical differences between these boards and real carts, there must be something wrong on my side. I need some help figuring it out. First, what kind of power supply should I be using? Is a 20 year old Atari supply really the best? Second, what does this distortion look like to you? RF? Should I try adjusting a pot? Which one? I have a VCS - CX2600A (4-switch woody). Finally, the fact that the person who wrote the game I tried to run, the person who designed the board I am using, and the person who put it together and tested it, wrote me back on a Sunday tells me that I have the right hobby! Quote Link to comment Share on other sites More sharing options...
video game addict Posted February 17, 2004 Share Posted February 17, 2004 Finally, the fact that the person who wrote the game I tried to run, the person who designed the board I am using, and the person who put it together and tested it, wrote me back on a Sunday tells me that I have the right hobby! Pretty cool huh! Quote Link to comment Share on other sites More sharing options...
antron Posted February 19, 2004 Author Share Posted February 19, 2004 Here is Kaboom! mirrored 16 times on a 27256. The point that the vertical lines break, moves up and down the screen when I turn the paddles. If I touch a capacitor to the one on the game PCB (104M) (in parallel, and the same value incidentally, so twice normal) the lines shift horizontally about as much as their width. Does the same on a 2732 (2/4K board) and/or with Super Breakout and/or on my friend's CX2600A. Unfortunately we have the same model so I am really only testing on one type of VCS. Quote Link to comment Share on other sites More sharing options...
joesmooth Posted February 19, 2004 Share Posted February 19, 2004 What board are you using with the 27256? If it is the 8KB bankswitch board, that is designed to run 8K ROM images with Atari F8 bankswitching. 2K and 4K ROMs should be used with the 2K/4K board. At least, that is how we designed them. For the 2K/4K board, the capacitor on the PCB is a bypass capacitor to help smooth the voltage going to the EPROM and 7404. I can't really be of much help on the forum, especially since we've never seen a problem like this before. I'd recommend to send the boards back to AtariAge so they can be analyzed and they can send you new ones. Even though they were tested, it will probabaly save a lot of heartache. Joe Quote Link to comment Share on other sites More sharing options...
antron Posted February 19, 2004 Author Share Posted February 19, 2004 What board are you using with the 27256? If it is the 8KB bankswitch board, that is designed to run 8K ROM images with Atari F8 bankswitching. I am using the 8K board. I just wanted to show that I am seeing this on both boards, and with any EPROM. In this case it is just bankswitching the same image if the magic address gets read. I can send them back, and I hope you see this too, but I don't see how if all the others you make have no problems. And I am seeing it with two different types. I am going to buy Thrust+ first, and if it does not have this problem I will send the boards back. Do your whole carts add any extra shielding besides the plastic? I am thinking it might be external interference. I am going to take it with me on a road trip this weekend to try in a different setting. I'll be back Sunday. Thank you Joe Quote Link to comment Share on other sites More sharing options...
Susuwatari Posted February 19, 2004 Share Posted February 19, 2004 Just a thought, do you have the RF shield in place on the 2600 console? Without the shield, the 2600 is liable to pick up all kind of noises. Quote Link to comment Share on other sites More sharing options...
antron Posted February 19, 2004 Author Share Posted February 19, 2004 Just a thought, do you have the RF shield in place on the 2600 console? Without the shield, the 2600 is liable to pick up all kind of noises. yes. Quote Link to comment Share on other sites More sharing options...
joesmooth Posted February 19, 2004 Share Posted February 19, 2004 I would also suggest trying another power supply, especially if you are using the same one to test your system and your friend's system. It might be introducing some awful noise. You can deal directly with Albert offline to handle the return and the rest of the support. Joe Quote Link to comment Share on other sites More sharing options...
Like us on Facebook
Follow us on Twitter
AtariAge on Instagram
Watch us on YouTube
Chat on Discord
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.