FB2+ Cart Port Workaround

[gnnash]

It seems that some people who are trying to add a cartridge port are running into an issue where 4K carts will not run. This is due to a bad trace leading to Pad 20, the A11 line. It turns out that Pad 20 is useless on these machines, but there is a pin on the ROM chip which can be easily soldered to instead of Pad 20.

 

Since my board is now covered with a sprawling mess of cartridge port wires, I have indicated the alternate Pad 20 location below on Emehr's Rev. C board cheat sheet (I hope you don't mind!) . Emehr, if you could please add this to your visual cheat sheet if you can, for Flashback 2+ modders, that would be great.

[+wongojack]

Awesome! - Thanks for doing this work for us

[player 0ne]

hey. would it be possible to remove the 40 games chip and install it on a black cart board? since the FB2 works without the chip, the chip should work without the board! do all the pins from the chip goto the pads for the cart port? i cant wait to play with mine. ill need some more to mess up though., off to the flea market!

[player 0ne]

Im doing the mod to mine right now. pad 20 and a11 have no continuity. so mine is prolly like this, right? if it wasnt for you pointing this out i would have never figured it. i mean, its labled, why wouldnt it work.

thank you soo much gnnash

[lbaeza]

Hi gmnash

 

Thank you very much for posting that Visual Cheat Sheet.

I'm in the middle of a FB2 cart port hack, so this will come in very handy.

 

Do you know of a popular 4K cart to test if the pin 20 is working OK?

 

Regards

[awace]

I see what happened this happens all the TIME with silk screen crocks when i worked at automed we would have vareinces in silk screen that only could be TOLD by human voice as a pass it along!!! they placed the circle in exact place that the pin needed was they just didnt use a jumper wire cause thats part of a MOD and they are cheap...

[+wongojack]

It seems that some people who are trying to add a cartridge port are running into an issue where 4K carts will not run. This is due to a bad trace leading to Pad 20, the A11 line. It turns out that Pad 20 is useless on these machines, but there is a pin on the ROM chip which can be easily soldered to instead of Pad 20.

 

 

@gnash - Hey did the Flashback on board games still work after you used this as a work around?

Edited November 6, 2011 by wongojack

[iesposta]

Cart mod finished. Flashback 2+ works great!

On board games still work fine. Installed a switch on the back to choose built in games/cartridge.

Now that it's finished, I saw the mod where the cartridge insert is in the lower left front.

That is so cool! Now I wish I had done it that way.

 

 

[kenjennings]

Is FB2 or FB2+ the preferred board for the cart port modification? I have one of each and thought it was the FB2+, but after reading about the pad 20 problem I'm starting to wonder.

Edited March 31, 2012 by kenjennings

[iesposta]

I would say the FB2+ model would be the best one for the cart modification.

Aren't there like three board versions of the FB2 - A, B & C?

Instead of soldering to pad 20, you just solder to a pin.

 

Tin all the pads and wires. This takes longer, but there is less chance of damage because you can solder very quickly and it won't overheat or lift traces.

 

I actually used old hard drive connector cable, but I didn't solder to the cartridge port pins. I just used two of the black plastic connectors. The connector cables usually have two black connectors and a gray connector. And there is enough wire to run from the circuit board to the cartridge port. One side fits right on to the cartridge pins from 1 to 12, and another one back to back for pins 13 through 24. Every other wire is connected to the pins. I guess connectors could come loose, but it works for me.

 

Another good tip is to temporarily secure the circuit board with the difficultly switches to the main circuit board with clips. The gray wires will break if stressed too much-- it happened to me (and WongoJack I believe.)

[tk3000]

Hello Folks,

I performed the mod, following the map the solering points/pads to a cartridge slot of an old non-functional atari2600 I had laying around. But I made a mistake of oversoldering the J3 pads and eronding them, so I tried to uncover the trace leading to such pads but I was not sure if I was accurate with the uppder pad. I would like to know if there is an alternative spot equivalent to the upper pad of J3 so that I could hook the wire there.

thanks

[iesposta]

Hello Folks,

I performed the mod, following the map the solering points/pads to a cartridge slot of an old non-functional atari2600 I had laying around. But I made a mistake of oversoldering the J3 pads and eronding them, so I tried to uncover the trace leading to such pads but I was not sure if I was accurate with the uppder pad. I would like to know if there is an alternative spot equivalent to the upper pad of J3 so that I could hook the wire there.

thanks

By upper, do you mean pad closest to the joystick ports? That appears to be ground.

The one closest to the epoxy blob, appears to come FROM the epoxy blob, so you would have to scrape the trace.

[awace]

I made the MOD TO A FB AND PUT IT INTO A ATARI2600 and used the orginal cart slot and used the b.w switch for built in and carts and ch3 ch2 ch4 switch for b.w also i used the 5v+ power supply too I scratched every thing exept the on off switch off the original 2600 board and wired them into the fb even the joystick ports and all cart slot wires I had to scape black and white switch completly off traces and was a pain in the but but it works it plays most games I havent tried a 4k game although since i read this along time ago i assume i soldered the a11 line already ..

PS it does play hangly man and hackem it also plays combat rock and some of my custom hackomatic II mod games too.

I also took a apollo cart apart and stole the idea on how to make my own carts using a old pacman cart since i had lots of them I used the apollo cart to see how they hooked the 7404 and its 4 pins up to the cart now i have a prototype to cheat from and once i hook the 7404 up properly I just add a socket and a 2732 and viola a 8k rom to the 2732 and viola I have my own custom cart..

[tk3000]

Hello Folks,

I performed the mod, following the map the solering points/pads to a cartridge slot of an old non-functional atari2600 I had laying around. But I made a mistake of oversoldering the J3 pads and eronding them, so I tried to uncover the trace leading to such pads but I was not sure if I was accurate with the uppder pad. I would like to know if there is an alternative spot equivalent to the upper pad of J3 so that I could hook the wire there.

thanks

By upper, do you mean pad closest to the joystick ports? That appears to be ground.

The one closest to the epoxy blob, appears to come FROM the epoxy blob, so you would have to scrape the trace.

 

ATARIAGE FOLLOWUP WITH FLASHBACK 2 ISSUES

Sorry for not having catched the response before. The flashback2 I have has silkscreen with a table of corresponding values and has pads with numbers in the back of circuit board to as a reference for the cartridge connections, but the soldering pads/points are in different positions from the ones I saw on photos here on the forum, maybe I have different circuit board revision (hopefully mine is now a fake one). The following is a photo of mine with some indication:

 

 

 

By upper pad I mean the soldering point pointed by a yellow line with a number 1 (pic above)., and I tested and there are indications that it may be a ground. The 1 and 2 marked numbered yellow lines ( added editing the image) are only to help visualize are equivalent to J3 on circuit board and they the ones I messed up and eroded the plated soldering point by overheating them, but I believe that I was able to scrape some of the mask of the circuit board trace and was able to solder it there (but not I am not 100% if I got the right trace).

 

Another object of confusion for me is the soldering point/pad 21, it is pointed on the pic above by a yellow line and the no. 3. In my circuit board the silkscreen no. 21 is surrounded by soldering points so it is not clear to which soldering point does the no. 21 refers to.

 

 

Thanks for any help

[iesposta]

Hello Folks,

I performed the mod, following the map the solering points/pads to a cartridge slot of an old non-functional atari2600 I had laying around. But I made a mistake of oversoldering the J3 pads and eronding them, so I tried to uncover the trace leading to such pads but I was not sure if I was accurate with the uppder pad. I would like to know if there is an alternative spot equivalent to the upper pad of J3 so that I could hook the wire there.

thanks

By upper, do you mean pad closest to the joystick ports? That appears to be ground.

The one closest to the epoxy blob, appears to come FROM the epoxy blob, so you would have to scrape the trace.

 

ATARIAGE FOLLOWUP WITH FLASHBACK 2 ISSUES

Sorry for not having catched the response before. The flashback2 I have has silkscreen with a table of corresponding values and has pads with numbers in the back of circuit board to as a reference for the cartridge connections, but the soldering pads/points are in different positions from the ones I saw on photos here on the forum, maybe I have different circuit board revision (hopefully mine is now a fake one). The following is a photo of mine with some indication:

 

 

 

By upper pad I mean the soldering point pointed by a yellow line with a number 1 (pic above)., and I tested and there are indications that it may be a ground. The 1 and 2 marked numbered yellow lines ( added editing the image) are only to help visualize are equivalent to J3 on circuit board and they the ones I messed up and eroded the plated soldering point by overheating them, but I believe that I was able to scrape some of the mask of the circuit board trace and was able to solder it there (but not I am not 100% if I got the right trace).

 

Another object of confusion for me is the soldering point/pad 21, it is pointed on the pic above by a yellow line and the no. 3. In my circuit board the silkscreen no. 21 is surrounded by soldering points so it is not clear to which soldering point does the no. 21 refers to.

 

 

Thanks for any help

 

Your 1. is ground.

3. is wrong. Should be to the left with the white circle around it.

You should have connection 20 (to the left of where 3 should go) to the 5th point from the left of the bottom right of the built in ROM chip.

[awace]

YOU KNOW IT WOULD HAVE BEEN WAY EASYER IF THEY JUST HAD A damn pin row like a ide holes but w no pins then we could have just hooked it up and they also could have just had a 0 resistor in the switch and nothing where the switch would have gone then we just add switch I dont know why they made it so damn hard to figure out I think they are so cheap they waste more time trying to be cheap and end up making it harder to produce if they just had a cart slot connection on the pcb then the wires would have been easyer to get to..

I would like the FB III to be like the FAKE psp PMP MP4 player I have it has a MINI sd slot and takes usb also has a touch screen I only paid like $20 at a HAMVENTION swap meet and it looks to be a cool device to run atari emulation or real atari now how hard could it be for the chinese to put 3 atari chips onto a nother chipset and have atari 2600 especially if its being made for atari..

ANWYAY I noticed the way i hooked it up i used the double pole b/w switch but up shorted gnd to one pin and down hooked one then on the other side it did the exact opposite when hooking one jumper on one side on the other pos hooked jumper wilst unhooking the other one but the COOL thing is when I load up a cart i do this every time

I start in built in mode then pick game mostly I choose missile command cause it has some weird effects although i pick asteroids cause i have a modded cart w rocks that look like aw now when i switch between built in 1st and external asteroids it does not change a thing exept the rocks go from normal to aw ® rocks now i have to wait for the © 1981 witch on mine says © © 2007) but then once that finishes i can swap between roms built in ones and external ones now I cant remember witch pin is being switched on and off on the cart but you can SEE the external game rom running in the interferance on the FB now if you are playing a internal game and remove the cart the interferance goes AWAY but if you replace it it comes back its slight and it moves w joystick movements this is something i notice on some games that have no RF cage they can interfere with them selfs in the video ..

I think this is caused by the 2764 or 2732 rom running in the chip it self anyway the cool thing is to load up missile command internal then swap to SNOOPY and the red baron then swap back to missile command if you do this there is a spot between both internal and external because of the way those 2600 six switcher switches get stuck between both states and makes the external rom stay connected to the internal rom and causing flahsback flashing type erounous rom reads causing artifacts in the code making the game screw up its cool one time the internal missile command had those weird SMART BOMBS comming up from the bottom the 2600 ones that get louder as they come then the score was just jumping up now i got lucky cause I pushed start(reset) and it let me play not making the joy go right it let me play it was one of the cooles games i played in a long time i got 100,000 or more then got sick of it but it was fun..

ALSO In case you were wondering yes hackem runs on the flashback just fine using a long 2764 I got one of the older ones running on a normal 2764 chip or a 2732 i cant remember witch chip w out looking but it runs just fine I have to start a built in game as usuall but it works great also if I put a PADDLE game in or racing game like indy 500 the paddles work w out having to do the 1 9 72 thing even though i knew that! the mod is not to hard its just the long hours of soldering the tabs to those mini tabs thats the hard part and using ide cable is a pain in the but I wish i had had some of the old rainbow cable I my dad had and I used to have.. it would have been easyer to do..

ALSO next time im going to use 100 foot VIDEO audio cables..

if anyone knows when or weather they are going to have a new FB3 come out let me know..

[tk3000]

Iesposta: thanks for the clarification, I can now see that there is small white line going from the no. 21 to the right soldering point/pad and the soldering point itself seems to have a faint white circle around it. I believe that I have all soldering points properly connected now (the only doubt is about the J3 whereon I scraped the pcb mask to has access to the traces, but I believe I got the right trace that goes that respective J3 pad). Unfortunately whenever I try to read a cartridge it shows the same nonsense on the screen (blue screen with some meaningless blotted multicolored large thing and small thing that seems like the tank in the game combat)

 

Moonsweeper: yeah, that is a very good point, having an ide like pin hole scheme would make much easier.

 

Thanks for the insights!

[awace]

swap the double pole double pole a10 built in memory lines on the switch around when on should be off when off should be on I had that wrong on the b/w switch I used I had scratched the original 2600 foil off the switch and at 1st had the wrong jumper on when it shouuld have been off wilst the other one was opposite .

example

the one jumper needs to be jumpered wilst the other one is off to make one state built in or cart work if it does not work then its the other way around meaning swap the jumper pins on the switch leaving the gnds alone..

this swap and viola when I tried it it booted REMEMBER to PULL the cart when turning it on and have it boot to built in castle 1st then select game THEN SWAP TO CART or it might not boot cart... I have found this works almost every time better than to try to boot to cart 1st... ONCE AND A GREAT WHILE IT SAYS

THIS AREA inetmtionally left blank ...

I cant remember witch word is spelled wrong but it has that cool rainbow effect... I had it come up and my freind says something not wired right I think that was it...

ALSO dont forget in ADV II the B/w switch is needed for the dark caves it lights them up in the mazes to allow you to see I think its a kid setting ..

anyway if you used a REAL 2600 case just use the ch3 ch2 switch RF switch for the b/w switch if its a OLD SUPER OLD ONE W SWITCH ON BOTTOM then I suggest adding youre own b/w switch..

I reused the 2600 power supply 5v+ regulator after the cap using the existing power switch so you have to unplug unit to kill power to reset I cant figure out how but somewhere its getting 5v+ when off oh yeah the cap stays charged so i have to turn off unplug power pack and turn back on for a second to kill off cap power then replug w power off then turn on..

***************************** you have the a10 and the built in jumpers backwards like i said thats what i had wrong wile one jumper is on the other is off for one state and opposite for the other but if you get the on jumper in the wrong spot it does what you describe

.

You will move the Black wire from IC2 to the other side of C4, then at J3 you'll need to add a jumper. I recommend you buy a single pull, single throw (SPST) Toggle switch and wire it across J3, this will allow you to enable/disable the onboard ROM chip. For the IC2 C4 connection a 3 way switch wired to the black wire on the common gnd

 

and one wire to the original location and an additional wire to C4 will allow you to switch from the original wire run to the C4 run. You'll need to drill open 2 holes for your two toggle switches. Its some extra work, but worth it since you'll be able to continue using the 40 built in games and then switch to using cartridges when needed.

damit that confised me ill have to look to see how i hooked the b/w switch up and where it goes and witch rev i have.

oh I see j3 jumper turns on built in memmory an removing jumper across j3 pads turns on built in memory.

the other switch is whell jumpering j3 one side to gnd as the other side of j3 is gnd then using the two sided b./w switch i must have c4 ed the black wire to open when not j3 gnded and back to orignal place when j3 open meaning I left out a step this is why i can FLASH from buit in game started like missile command to cart missile command or built in missile command to snoopy on 2764 chip witch when flash back to built in missile command makes cool errors on missile command I THINK THIS IS THE REAL REASON ITS CALLED THE flashback I think i like the missed step leaving the built in rom on lets you choose the a10 line of the cart this way or built in memmory so j3 must switch to the cart software so I think thats what i swapped and got that this space imtentionally left blank ..

COOL I will look to see what i did sometime before newyears.

this is the rev i was using

http://www.youtube.com/watch?v=S2Lbcw08bbQ

Edited July 14, 2012 by awace

[iesposta]

Here is the original image updated to show the location of the Soft Reset switch.

I have not tested this yet, but it matches the other board Soft Reset points.