+batari Posted October 28, 2016 Share Posted October 28, 2016 Hi, Looks like the remaining carts sold quickly. But don't fret. I decided to order a small run of 20 with minor changes to the board. The changes are mostly for easier assembly, and it may be the same as the production version of the board. The new board I just ordered fixes the issue where the POKEY would need to be removed to connect the cart to USB. I will offer these new boards for sale to those who have PM'ed and posted here. They should be here in a few weeks. For what it's worth, it is possible to fix existing carts to address the POKEY/USB issue - solder a capacitor between the +5v and GND pins of the POKEY. The capacitor should be at least 22 uF. If you are worried about damaging the board with soldering, you could probably solder a capacitor to the top of the pins of the POKEY chip itself. If any Concerto owners want to send me a POKEY chip in the mail, I would be happy to solder a capacitor onto the pins and mail it back. The boards that shipped out today have this repair on them (I used surface mount parts on these, and the repair should be obvious.) The ones shipped out yesterday unfortunately do not. 7 Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted October 28, 2016 Share Posted October 28, 2016 22uF is pretty large for reducing transient bus noise (generally only a .1 - .22uF ceramic disk or "chicklet" is used across a chip's supply pins). That's 2 orders of magnitude increase! Would a 22uF electrolytic between GND and VCC cause an inrush of current on the cart bus when power is supplied to the 7800? Link to comment Share on other sites More sharing options...
+batari Posted October 28, 2016 Share Posted October 28, 2016 It isn't bus noise. It seems to be a power issue. There should be no issue with power spikes when the 7800 is powered on. Resistors will drain the cap before that happens. Link to comment Share on other sites More sharing options...
RevEng Posted October 28, 2016 Share Posted October 28, 2016 That's interesting. Some 7800's seem to have a problem with the Dungeon Stalker homebrew and the AtariVox SpeakJet getting reset (it's one of the few 7800 homebrew's with voice, and a lot of it) I've been suspecting 7800 power condition being at the heart of the issue. Link to comment Share on other sites More sharing options...
Jinks Posted October 28, 2016 Share Posted October 28, 2016 Heres another dumn question.. Why would I need to plug in usb to the cart? It uses sd card for the games right? Link to comment Share on other sites More sharing options...
+batari Posted October 28, 2016 Share Posted October 28, 2016 USB is for development or for reflashing in the case of a BIOS corruption. Most will never need to use it, but if you do need to, having to pull the POKEY chip is inconvenient. Link to comment Share on other sites More sharing options...
Jinks Posted October 28, 2016 Share Posted October 28, 2016 USB is for development or for reflashing in the case of a BIOS corruption. Most will never need to use it, but if you do need to, having to pull the POKEY chip is inconvenient.Ok thanks for the info! Can't wait to try er out!! Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted October 28, 2016 Share Posted October 28, 2016 That's interesting. Some 7800's seem to have a problem with the Dungeon Stalker homebrew and the AtariVox SpeakJet getting reset (it's one of the few 7800 homebrew's with voice, and a lot of it) I've been suspecting 7800 power condition being at the heart of the issue. Dungeon Stalker works flawlessly on mine with AtariVox (had to use an extension cable though) so I take it as a good sign regarding compatability. My Best AV 7800 (no expansion port) runs everything I've ever thrown at it. Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted October 28, 2016 Share Posted October 28, 2016 USB is for development or for reflashing in the case of a BIOS corruption. Most will never need to use it, but if you do need to, having to pull the POKEY chip is inconvenient. I know I asked this already but will a 40-pin socket fit inside the shell? Also does the Pokey prevent BIOS updates through the SD card? Link to comment Share on other sites More sharing options...
+batari Posted October 28, 2016 Share Posted October 28, 2016 I know I asked this already but will a 40-pin socket fit inside the shell? Also does the Pokey prevent BIOS updates through the SD card? If you are cutting your own casing, some trimming may be needed to get it all to fit but it does fit. Without the capacitor, the POKEY only prevents BIOS updates through USB. BIOS updates through the menu are not affected. Link to comment Share on other sites More sharing options...
Mattman007 Posted October 28, 2016 Share Posted October 28, 2016 If you haven't already filled your list for the next 20 please add me for 1. Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted October 28, 2016 Share Posted October 28, 2016 If you are cutting your own casing, some trimming may be needed to get it all to fit but it does fit. Without the capacitor, the POKEY only prevents BIOS updates through USB. BIOS updates through the menu are not affected. I can add a cap that's not a problem. Also I'm pretty good at Dremeling out plastics. I just wouldn't want to have to cut a rectangular hole in the case which would be ugly. Just for clarity, a 22uF electrolytic cap is connected between the VCC and GND of the Pokey socket, right? Link to comment Share on other sites More sharing options...
fille1976 Posted October 28, 2016 Share Posted October 28, 2016 Batari,pmed you 26-10,did you received it? Also intrested in concerto cased if possible. Link to comment Share on other sites More sharing options...
Mayhem Posted October 28, 2016 Share Posted October 28, 2016 Likewise, please put me down on the list for the new board when it comes in Link to comment Share on other sites More sharing options...
+Stephen Posted October 28, 2016 Share Posted October 28, 2016 Excellent news - I'll have to dig my 7800 out of storage now. Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted October 29, 2016 Share Posted October 29, 2016 Well I got my Concerto assembled today with transplanted Pokey chip. Pictured next to it's brother Harmony on the right. The cartridge used to be a Ball Blazer but I gave it a higher purpose. What are you guys experiences running ROMs on the Concerto? What games work and what games cause problems? I can confirm BallBlazer runs and the Pokey chip is working great. First thing I did was copy the Good 7800 set and load all the Pokey homebrews I could find linked from this thread. It seems nearly every ROM I load (modern or bitd) is corrupted in some way, yet the corruption is not the same after multiple loads. Sometimes it's pure crash on startup, sometimes sprite corruption, sometimes the game plain acts weird, broken physics, etc, and the behavior is a little different every time. For instance, after several attempts, I finally managed to get Pacman 320 Pokey version to run: I guess one could argue this thing is still in Alpha state. By no means am I trying to discredit Batari's amazing work, but I may just set it aside and wait for the next firmware update. Will I have better luck with loading ROMs if I desocket the Pokey? Lastly, Batari mentioned adding a 22uF cap. Forgive my ignorance but which pins do I connect the leads to? Link to comment Share on other sites More sharing options...
Trebor Posted October 29, 2016 Share Posted October 29, 2016 Lastly, Batari mentioned adding a 22uF cap. Forgive my ignorance but which pins do I connect the leads to? "...solder a capacitor between the +5v and GND pins of the POKEY. The capacitor should be at least 22 uF..." Link to comment Share on other sites More sharing options...
Laner Posted October 29, 2016 Share Posted October 29, 2016 I haven't done extensive testing, but the handful of 7800 titles I tried from the GoodMerge set (Xevious, Ballblazer, Pole Position II, One on One, Asteroids) worked fine. Haven't tried any homebrews yet. Pitfall II won't load, but I assume that's due to it being a special case. Link to comment Share on other sites More sharing options...
Jinks Posted October 29, 2016 Share Posted October 29, 2016 "...solder a capacitor between the +5v and GND pins of the POKEY. The capacitor should be at least 22 uF..." So between the pins you mean bend 5v and ground on pokey chip up and solder the capacitor between the chip and the board for each pin?Maybe a picture of someone that has done this and a source for the part needed that would work would be helpfull. If the pokey was installed as is would the menu based bios updates be good enough or thr usb method would need to be used in case the bios is corrupted and can not load? Link to comment Share on other sites More sharing options...
Jinks Posted October 29, 2016 Share Posted October 29, 2016 Oh will this play 2600 games? I can not remember. Link to comment Share on other sites More sharing options...
Lord Thag Posted October 29, 2016 Share Posted October 29, 2016 Add me to the list as well Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted October 29, 2016 Share Posted October 29, 2016 "...solder a capacitor between the +5v and GND pins of the POKEY. The capacitor should be at least 22 uF..." Forgive my ignofance but I don't know where GND and VCC are on the Pokey chip. Tnere are no marls on the bottom og thePCB. I wanted to solder the cap on the back of the board but I nedd to know which pins to solder too. Alsp I tried desocketing the Pokey chip and the majority of 79-0 titles (homebrew or bitd) still have crash or have major corruption issues so it isn't the Pkey causing issues. Nice tning most 2600 games that don't use DCP or special chips run fine on it. EDIT: Forgive the typos but I misplaced the N3DS stylus. Stubby man fingers don't work well... Link to comment Share on other sites More sharing options...
RevEng Posted October 29, 2016 Share Posted October 29, 2016 Possibly the whole cart needs the extra power dropout protection on some consoles. There's a pinout at the POKEY wikipedia entry. Ground is pin 1, +5v is pin 17. 1 Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted October 29, 2016 Share Posted October 29, 2016 I haven't done extensive testing, but the handful of 7800 titles I tried from the GoodMerge set (Xevious, Ballblazer, Pole Position II, One on One, Asteroids) worked fine. Haven't tried any homebrews yet. Pitfall II won't load, but I assume that's due to it being a special case.Did you try Donkey Kong, DK Jr, and Galaga? Donkey Kong crashes before I can finish the first stage. Sometimes walking left doesn't work but I can left jump. It usually crashes when I first attempt to jump a barrel. DK Jr lets me move around, but I get stuck as soon as I grab a vine. Collision with clap traps doesn't detect and I'm stuck until time expires. Galaga, I get stuck at the ready screen. Sometimes it freezes here, others I can fire bullets and move back and forth but the swarm never comes. Xevious. Sometimes I can play normally, other times theλ entire screen gets corrupted and I can't see my ship. Pacman320 Pokey and Ms Pacman 320 Pokey: Title screen loads fine. Usually game crashes when it draws the maze. Rarely I am able to start a game. Pokey audio plays fine but colision detection with the maze doesn't work and I can travel through walls at will. Sometimes on Pacman the mazecorrupts and dots are random dispersion. Froggy (Pokey): graphics are totallh corrupted but audio plays fine. Occasionally the trucks do not move and tje sprite corruption on the water area is so bad I cannot see whare the objects are and I die. bentey Bear (pokey): Bently falls through the floor three times. Cannot play, and no sound. DK PK: black screen never works. Super Circus (pokey): title loads, cannot start game. 2600: Most non-melody games with strait bank switching boot and play fine. I fpund a menu issue where "unsuported" error, "press fire to return to menu" reloads the unsupported ROM. Occasionaly an extremely light tap (one frame) allowsme to retirnto the menu. Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted October 29, 2016 Share Posted October 29, 2016 Possibly the whole cart needs the extra power dropout protection on some consoles. There's a pinout at the POKEY wikipedia entry. Ground is pin 1, +5v is pin 17. Just for verification before I solder anything, can someone please confirm this is where I need to attach the 22uF cap? (View from bottom of PCB) Link to comment Share on other sites More sharing options...
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