Andromeda Stardust Posted February 8, 2017 Share Posted February 8, 2017 Does anyone have a 4-switch or 6-switch (any model, ntsc or pal) that the bus stuffing demos fail on? I'd test mine but I cannot locate my Harmony cart atm... Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted February 8, 2017 Share Posted February 8, 2017 I'd test mine but I cannot locate my Harmony cart atm... How that? My Cart never leaves the console. 3 Quote Link to comment Share on other sites More sharing options...
MayDay Posted February 9, 2017 Share Posted February 9, 2017 I agree, also with the Jr. But IMO that shouldn't stop BusStuffing. Maybe there is a way to overcome the problem by software, which just cannot be seen right now? Or maybe the Jr. consoles can be fixed with a mod like some 7800 had to be fixed for certain Atari 2600 games? Also, the Cosmic Ark trick doesn't work right on many Jrs, still this is accepted as an incompatibility of the hardware, not the software. Didn't mean to imply that work on bus stuffing should stop, only that the end result should work on "stock" hardware including the Jr. I would help test as I have a Jr. (and a 4-switch), but I don't happen to have a Harmony cart. I don't see them in the AA store, are they still available somewhere? I do have a Krokodile Cartridge, but I'm guessing it doesn't have the correct hardware inside to run this? Also I haven't used it in several years, so I'm not even sure offhand that it still works. Quote Link to comment Share on other sites More sharing options...
+SpiceWare Posted February 9, 2017 Author Share Posted February 9, 2017 Order from the Harmony Cart site. Quote Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted February 9, 2017 Share Posted February 9, 2017 Order from the Harmony Cart site. There should really be a link to the Harmony page from the AtariAge store. File Harmony under hardware, then instead of "add to cart", provide a link to the order page. Quote Link to comment Share on other sites More sharing options...
+SpiceWare Posted February 9, 2017 Author Share Posted February 9, 2017 Aha, I see the confusion - AtariAge doesn't sell the Harmony, they just host the site for batari. AtariAge hosts a number of other sites too, the AA Store could become overwhelmed with non-AA products if Al linked to everything else hosted by AA. A search of "Harmony Cart" at DuckDuckGo (and Google, if you prefer) returns batari's site as the first no-ad result. Quote Link to comment Share on other sites More sharing options...
ZackAttack Posted February 17, 2017 Share Posted February 17, 2017 I was able to collect some data using the test program that SpiceWare supplied and found that bus stuffing breaks when the Harmony is driving a logic low on a data pin, and the resulting voltage at the pin is higher than 1.39 V. This happens when the resistance between the harmony cartridge and the data bus is greater than 39 ohms. When the resistance is less than 1 ohm there is a comfortable margin of 0.47 V, at least on my four switch console. I realize that a sample size of one really doesn't provide enough data points to support a conclusion, but having a margin of nearly 0.5 V leads me to believe that bus stuffing will work on most 2600 consoles. Noting that it takes only 39 ohms of resistance between the harmony cartridge and the data bus to break bus stuffing, it's important to have the contacts perfectly clean on both the Harmony cartridge and on the 2600 cartridge connector. I've seen oxidation on connector contacts introduce 50 ohms or more of resistance. It's also possible, as Kosmic Stardust and ZackAttack pointed out, that some TIA chips and/or CPUs may have odd timing issues that prevent bus stuffing from working. However from what I'm seeing on the scope, the timing margins are good, and bus stuffing should work fine in most cases. Which data pin did you collect this data from? Quote Link to comment Share on other sites More sharing options...
+SpiceWare Posted February 21, 2017 Author Share Posted February 21, 2017 ZackAttack and I have come up with a test ROM to clarify which bits are not getting stuffed. If you see something other than this please post a photo: Edit: use new version in reply 137 PF1_power2_20170221.bin Quote Link to comment Share on other sites More sharing options...
TheHoboInYourRoom Posted February 22, 2017 Share Posted February 22, 2017 ZackAttack and I have come up with a test ROM to clarify which bits are not getting stuffed. If you see something other than this please post a photo: IMG_8416.jpg PF1_power2_20170221.bin What a mess. Quote Link to comment Share on other sites More sharing options...
+SpiceWare Posted February 22, 2017 Author Share Posted February 22, 2017 Thanks! I guess we shouldn't have used bus stuffing for the digits, they became useless. I'll whip up a new build in a bit, the timer just went off for my dinner. Quote Link to comment Share on other sites More sharing options...
+SpiceWare Posted February 22, 2017 Author Share Posted February 22, 2017 Step 1 - "break" bus stuffing to match: 1 Quote Link to comment Share on other sites More sharing options...
+SpiceWare Posted February 22, 2017 Author Share Posted February 22, 2017 Step 2 - disable the "break" and rewrite the digits: Step 3 - reenable the "break" to make sure digits still visible: PF1_power2_20170221b.bin Quote Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted February 22, 2017 Share Posted February 22, 2017 What a mess. power2.jpg What console model and preferably PCB revision do you have? Quote Link to comment Share on other sites More sharing options...
TheHoboInYourRoom Posted February 22, 2017 Share Posted February 22, 2017 What console model and preferably PCB revision do you have? A 2600 Jr Rev. A. I didn't think to check the board revision when I opened it a few weeks ago. I could take a look again tomorrow. Quote Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted February 22, 2017 Share Posted February 22, 2017 A 2600 Jr Rev. A. I didn't think to check the board revision when I opened it a few weeks ago. I could take a look again tomorrow. Juniors and many 7800s really do not seem to like the bus stuffing demos for some reason. Quote Link to comment Share on other sites More sharing options...
TheHoboInYourRoom Posted February 22, 2017 Share Posted February 22, 2017 (edited) A 2600 Jr Rev. A. I didn't think to check the board revision when I opened it a few weeks ago. I could take a look again tomorrow. Oh yeah, I figure I should ask this beforehand (to possibly save any unnecessary work): is the revision number usually on the top or bottom of the board? Never mind. Edited February 23, 2017 by TheHoboInYourRoom Quote Link to comment Share on other sites More sharing options...
TheHoboInYourRoom Posted February 23, 2017 Share Posted February 23, 2017 What console model and preferably PCB revision do you have? CO21503 REV E 1 Quote Link to comment Share on other sites More sharing options...
netspecter Posted February 23, 2017 Share Posted February 23, 2017 (edited) CO21503 REV E jr-board-rev.jpg My Atari 2600 Jr REV E displays the demo properly. What's strange is the label on the board seems to be in a different location. I also tested a REF F which also worked fine. I have three other juniors, don't ask, that I haven't taken apart yet so I'm not sure their revisions. One of them didn't display properly. Unplugging and replugging the cartridge changed the results though still not correct. It makes me think the connection quality could be the issue. Edited February 23, 2017 by netspecter Quote Link to comment Share on other sites More sharing options...
+SpiceWare Posted February 23, 2017 Author Share Posted February 23, 2017 I have three other juniors, don't ask, that I haven't taken apart yet so I'm not sure their revisions. One of them didn't display properly. Unplugging and replugging the cartridge changed the results though still not correct. It makes me think the connection quality could be the issue. Try cleaning the Harmony Cart's connector with a Q-Tip soaked in alcohol, those connectors (bottom of reply #99) seem to get dirtier than normal for some reason. Also squish another Q-Tip, as seen in #107, soak it in alcohol and clean the cartridge port. Quote Link to comment Share on other sites More sharing options...
MayDay Posted February 26, 2017 Share Posted February 26, 2017 (edited) My 4 switch displayed everything correctly once I got it working. My Jr. did not. Images of the Jr. running each .bin attached. Edited February 26, 2017 by MayDay Quote Link to comment Share on other sites More sharing options...
MayDay Posted February 26, 2017 Share Posted February 26, 2017 And the diagnosis program. Quote Link to comment Share on other sites More sharing options...
WIZZARD77 Posted March 13, 2017 Share Posted March 13, 2017 Sorry don't have a pic but ran your test program through my 4 Switch and I get a black bar through #7. I cleaned both the machine and the cart and still the same result. On an interesting side not I have been testing Space Cactus Canyon from bjbest60 in the batari basic forum and I have not had any problem with the betas until ver 2.3 which crashes or restarts to title. Now Stanjr has been playing this as well and had no problems, do you think these problems could be related? Quote Link to comment Share on other sites More sharing options...
+SpiceWare Posted March 13, 2017 Author Share Posted March 13, 2017 I don't think they'd be related. Quote Link to comment Share on other sites More sharing options...
ZackAttack Posted March 24, 2017 Share Posted March 24, 2017 (edited) Would the three of you please try the following test program on the systems where the previous test program failed? Instead of stuffing a 0 over a 1, it stuffs a 1 over a 0. This fixed the problem for MayDay and I'd like to see if it works for you too. If it's working correctly you should see this: Sorry don't have a pic but ran your test program through my 4 Switch and I get a black bar through #7. What a mess. power2.jpg One of them didn't display properly. Unplugging and replugging the cartridge changed the results though still not correct. Edited March 24, 2017 by ZackAttack 2 Quote Link to comment Share on other sites More sharing options...
TheHoboInYourRoom Posted March 24, 2017 Share Posted March 24, 2017 (edited) The forum is saying I don't have permission to download it. EDIT: I can download other attachments in this thread just fine, even in a private window. It's just this latest ROM that I can't get. Edited March 24, 2017 by TheHoboInYourRoom Quote Link to comment Share on other sites More sharing options...
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