New Incognito install not working

[StickJock]

I finally got around to installing my Incognito.  I had to wait for my DuPont crimper & connector kit to come in.

I just finished the first part of the install on my 800.  I used the directions on @lotharek's site as well as the @flashjazzcat's video.  I added the two jumper wires, replaced the two resistors, and soldered on the 6 header wires.  I made my own DuPont header, so my wire colors don't match.  I am using:

1=Green

2=Blue

3=Purple

4=Grey

5=White

6=Black

I pulled out the 74LS42 and plugged in the ribbon cable.  I plugged the two cables into the Incognito board & plugged it & the CPU board into the 800.  I power on the unit and nothing happens.  I get a black screen and no "fart" noise.

 

So I unplug the Incognito & the ribbon cable and put the 74LS42, ROM board & RAM boards back in.  It then powers up properly.  I swap out these parts and try the Incognito again.  Same thing - black screen & no fart.

 

I've included the pics of my mods, in case someone sees where I made a dumb mistake.  I've already tried beeping out the connections from the back of the connector on the Incognito board to the 800, to verify that my first-try DuPont connector is making proper electrical connections.  I also beeped out pins 1-16 of the ribbon cable from the back of the Incognito board to the 800 board, so the ribbon cable connections are seated properly.

 

Any idea where I went wrong?  Or maybe some other diagnostic that I can do?

 

Edited July 31, 2020 by StickJock
Added Incognito tag

[Roydea6]

Do you have this done on the back of the motherboard.

 

[StickJock]

1 hour ago, Roydea6 said:

 

Do you have this done on the back of the motherboard.

 

Yup.  That's the first pic (short blue wire).

 

[TGB1718]

The wire colours shown in @flashjazzcat video are not always what you get, mine were very different, on your original header

 

are they as follows

 

Thanks, just found a photo on this thread from @DrVenkman , his has the same wire colours/sequence as mine, so from that

 

Pin 1 Green

Pin 2 Orange

Pin 2 Yellow

Pin 4 White

Pin 5 Red

Pin 6 Black

 

 

and from @flashjazzcat in case yours are different to that

Ignore the wire colours and go by the pin numbers. Pin 1 is at the end of the 6-way header closest to the edge of the PCB.

 

Lots of good info on this link It's rather a long topic, but page 28 covers the problems with the wiring I had

 

Edited July 31, 2020 by TGB1718
Update

[flashjazzcat]

29 minutes ago, TGB1718 said:

Ignore the wire colours and go by the pin numbers. Pin 1 is at the end of the 6-way header closest to the edge of the PCB

That's exactly what I have advocated all along. That's why there are signal labels in the video.

[StickJock]

Yes, as I said, I made my own cable with it's own colors that don't match either the new or old stock cables.  I had to make my own cable since the new one didn't come with the DuPont connector, and I had to make the wires on pins 1 & 6 longer in order to reach the ANTIC pins.

 

I listed out the colors that I am using in my original post, and included pics showing the connector and all of the solder points. 

 

I have triple checked all of the connections, and beeped them out from board to board.  I can't see where I messed up.  It boots when I revert to the original ROM & RAM & 74LS42 chip, so the motherboard & CPU board are fine.  I've only left it powered up for a couple of seconds with each test.  I noticed that the power LEDs fade out slowly when I cut power.  I don't recall them doing this in the original configuration.  Did I get a dud?  Even though I only have power on for a few seconds, the Incognito board seems to "smell" hot, and the chips on it seem to be warmer than ambient.

 

[+DrVenkman]

26 minutes ago, StickJock said:

Yes, as I said, I made my own cable with it's own colors that don't match either the new or old stock cables.  I had to make my own cable since the new one didn't come with the DuPont connector, and I had to make the wires on pins 1 & 6 longer in order to reach the ANTIC pins.

 

I listed out the colors that I am using in my original post, and included pics showing the connector and all of the solder points. 

 

I have triple checked all of the connections, and beeped them out from board to board.  I can't see where I messed up.  It boots when I revert to the original ROM & RAM & 74LS42 chip, so the motherboard & CPU board are fine.  I've only left it powered up for a couple of seconds with each test.  I noticed that the power LEDs fade out slowly when I cut power.  I don't recall them doing this in the original configuration.  Did I get a dud?  Even though I only have power on for a few seconds, the Incognito board seems to "smell" hot, and the chips on it seem to be warmer than ambient.

 

I think the wires to your resistors on the main board are incorrect. On mine, those wires go to pins 3 and 4 of the Incognito connector. On yours, you have them wired to pins 3 and 5. Pin 5 should be wired to one of the vias on the main board adjacent to the RAM slots. 

 

EDIT: See this set of instructions, originally posted by Candle waaaaay back when. The pin assignments for P5 are shown in this post, and solder locations with signal names are also labeled in the photos. 

 

Edited July 31, 2020 by DrVenkman

[StickJock]

8 minutes ago, DrVenkman said:

I think the wires to your resistors on the main board are incorrect. On mine, those wires go to pins 3 and 4 of the Incognito connector. On yours, you have them wired to pins 3 and 5. Pin 5 should be wired to one of the vias on the main board adjacent to the RAM slots. 

Thanks for taking a look at my install.  I appreciate it.

 

I have the grey & purple (pins 3 & 4) wires going to the resistors, and the white & blue (pins 5 & 2) wires going to the vias.  Maybe the grey wire looks white on your monitor?

[+DrVenkman]

Well, in that case I don’t know what else you’ve got going on. You don’t show the incognito installed - to be 100% clear and rule out EVERYTHING, are you installing the board itself facing the back of the machine? 

[StickJock]

Just now, DrVenkman said:

Well, in that case I don’t know what else you’ve got going on. You don’t show the incognito installed - to be 100% clear and rule out EVERYTHING, are you installing the board itself facing the back of the machine? 

LOL.  Yes, of course.

 

It is kinda funny that Atari didn't key their card slots.  I guess that they relied on the cards' cases to only allow them to go one way, and then abandoned the cases after they caused overheating.

[R.Cade]

Seems OK at first glance. You didn't show the ribbon to socket connection though. However it should be keyed and obvious how it goes.

 

Edited July 31, 2020 by R.Cade

[StickJock]

35 minutes ago, R.Cade said:

Seems OK at first glance. You didn't show the ribbon to socket connection though. However it should be keyed and obvious how it goes.

 

The last pic shows all three connections - the 6-pin & ribbon on the Incognito, and the other end of the ribbon in the dip socket.  I beeped out all 16 pins from board to board, starting at pin 1 at both ends.

 

[TGB1718]

As you've double checked everything and it still won't work, maybe you got a duffer ?

 

[flashjazzcat]

Those CPU board connections: check them about a dozen times. Not that I'm saying they're wrong, but there are two different chip layouts on the CPU boards and it's very easy to solder wires not only to the wrong legs of ANTIC, but even to entirely the wrong chip. The Incognito will work without these two connections (they are there to provide ANTIC extended RAM access), so if absolutely desperate, try the machine with those two jumper wires disconnected.

[StickJock]

4 minutes ago, TGB1718 said:

As you've double checked everything and it still won't work, maybe you got a duffer ?

 

Triple checked!

 

I think that the next thing to do is find someone local who has a working Incognito, and see if they are willing to try this one out in their machine.  Should be a simple test to just unplug their board, unplug connectors, plug connectors into my suspect board, and plug the board into the known-good Incognito-modded system.  If it boots, then it's my install.  If it doesn't, then maybe the board is hosed?

 

Is there anyone in the SF Bay Area willing to test this board out for me?

[StickJock]

8 hours ago, flashjazzcat said:

Those CPU board connections: check them about a dozen times. Not that I'm saying they're wrong, but there are two different chip layouts on the CPU boards and it's very easy to solder wires not only to the wrong legs of ANTIC, but even to entirely the wrong chip. The Incognito will work without these two connections (they are there to provide ANTIC extended RAM access), so if absolutely desperate, try the machine with those two jumper wires disconnected.

Yeah, I looked up the chip part numbers on the board to make sure that I had the right chip before I started.  I also checked that the layout on the back of my CPU board matched the one on Lotharek's site.  So, I'm pretty sure that I have the right chip & pins.

I checked all of my solder points for bridges and didn't see any.  Also, the 800 still works with the old RAM & ROM installed, so that's something.

I can desolder those two wires tomorrow to see if it boots without them.  What is the bare minimum that I need in order to boot anything?  Can I unplug the 6-pin connector, or is it just the two wires going to the CPU board that I can disconnect?  I can't see anywhere that I deviated from the install directions, and I have beeped out all of the connections.  I'm really starting to think that maybe I got a bad unit.  ?

[bandit]

Looked at your install and did not see where the Disk swap wire went. That is the one that can kill the board, remove CPU board wires and LED/Diskswap and check for boot.

 

The Disk swap is to Ground only, no voltage.

 

 

[StickJock]

1 hour ago, bandit said:

Looked at your install and did not see where the Disk swap wire went. That is the one that can kill the board, remove CPU board wires and LED/Diskswap and check for boot.

 

The Disk swap is to Ground only, no voltage.

 

 

I haven't gotten to that stage of the install.  I was testing the functionality before doing the power board mod.  I haven't even plugged anything into the 3-pin connector.

[StickJock]

 

On 7/31/2020 at 12:24 PM, flashjazzcat said:

so if absolutely desperate, try the machine with those two jumper wires disconnected.

Yes, I am absolutely desperate!  I tried the machine with those two jumper wires disconnected, and... no dice.  It has the exact same behavior.  At power up, I get a fast green flash on the screen, and then totally black.

 

The machine still works if I revert to the original ROM & RAM boards, and replace the 74LS42.

 

Any other ideas?

 

[+DrVenkman]

5 minutes ago, StickJock said:

Any other ideas?

Do you have an EPROM programmer and adapter for the logic chip used on the Incognito? If for some reason the chip is corrupted or never got flashed properly to begin with, you might have similar symptoms. Otherwise you should probably contact Lotharek regarding a return or replacement.

[StickJock]

No, I don't have an EPROM programmer.  I used to use the gear at work, before I got laid off & retired.

 

The other thing to try is if there is someone near me who has a working Incognito installed that can try using my board. That would definitively show if the board is working or not.

 

[+skr]

9 hours ago, StickJock said:

No, I don't have an EPROM programmer.  I used to use the gear at work, before I got laid off & retired.

 

The other thing to try is if there is someone near me who has a working Incognito installed that can try using my board. That would definitively show if the board is working or not.

 

If you have an AtariMax cart, you can use that one to flash the chip! No extra hardware needed. I used that several times to flash the chip of my U1MB.

[+DrVenkman]

2 hours ago, skr said:

If you have an AtariMax cart, you can use that one to flash the chip! No extra hardware needed. I used that several times to flash the chip of my U1MB.

His system isn’t even booting so - even assuming it’s a corrupted chip - will a cartridge-based solution even work?

[+skr]

I think he somewhere stated, that he changed something back and could make it boot.

 

Anyway: The install is quite easy to remove, so my first step would be to go back to original config and see, if it is working. And if it does, he can attempt programming the chip, if needed.

 

And I have to admin, that I always forget, that some people do have one Atari only, and not lots of. Sorry.

[+DrVenkman]

21 minutes ago, skr said:

I think he somewhere stated, that he changed something back and could make it boot.

 

Anyway: The install is quite easy to remove, so my first step would be to go back to original config and see, if it is working. And if it does, he can attempt programming the chip, if needed.

 

@StickJock already said that if he removes the Incognito and reinstalls the stock OS and RAM boards, the machine will boot but no luck with the Incognito, even with the wires to the CPU board disconnected per @flashjazzcat’s suggestion. 

 

So if there are no other issues with wiring or board modifications (and there doesn’t seem to be), the only other thing I could think of was re-flashing the Incognito, but he has no way to do that, it sounds like. 

 

Time to contact Lotharek, I think.