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Atari Jaguar P1 red buttons along with 1,4,7 not working.


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2 hours ago, cubanismo said:

Are you certain 8 works on the "good" port or other Jaguar you had?

Yes I tried it right after using the same controller.  The replacement parts should be here Friday or Saturday.  I'm starting to think that chip failed in a weird way.

 

If U26 really is bad it would make sense it caused another issue on U22 when swapped.  

Edited by aapuzzo
13 hours ago, aapuzzo said:

Are pins 2 & pin 18 on U26 the correct pins I should be comparing because pin 18 looks like it is ED0 and not ED1? 

From the schematic I have you should be looking at pins 3 & 17.

13 hours ago, aapuzzo said:

Where does the pulse on player 1 pin 3 get generated?

Not 100% sure as  it ahs been some time since I done some basic dabbling when it comes to programming the Jaguar, so my memory is a bit fuzzy.

From the schematic I would say the origin of the ED1 signal is pin 17 of U26, but that pin is connected to D1 of Data Bus, so in theory you could assign controller read code to either the 68000, Tom/Jerry or both as they are all connected to the data bus and are thus capable of reading/wring data to the D1 line.

For some reason I think that generally the 68000 is used, but I may be wrong as Jerry is the source of the JOYCSL lines that controls the controller data flow on U18, U20, U21 & U25, I am sure that either @Zerosquare or @cubanismo would know.    

 

10 hours ago, aapuzzo said:

Just figured out where the issue is!!  I think U26 was bad.  I swapped it with U22 since it had the same part number and now 1,3,6 and the red buttons are working and only button 8 seems to be not working.

What about 1, 4, 7, B & * which was the initial issue you reported?

 

If the Row strobe for 8 was the issue it should also affect 0, C, 2 & 5, being on the same Row. If it was the pull up resistor or and issue with the input/output to U1in the controller/bad cable then it should also affect 7, 9 & Down being in the same column.

Therefore if neither of those are the case then logically the issue should lie within the controller, either the button itself, Diode D8 or the connection to one of those. as that is the only way it can be non functional in isolation from any other buttons connected to the same Row/Column. 

4 hours ago, Stephen Moss said:

What about 1, 4, 7, B & * which was the initial issue you reported?

 

If the Row strobe for 8 was the issue it should also affect 0, C, 2 & 5, being on the same Row. If it was the pull up resistor or and issue with the input/output to U1in the controller/bad cable then it should also affect 7, 9 & Down being in the same column.

Therefore if neither of those are the case then logically the issue should lie within the controller, either the button itself, Diode D8 or the connection to one of those. as that is the only way it can be non functional in isolation from any other buttons connected to the same Row/Column. 

1,4,7 are working now along with and the red buttons and they weren't before swapping U26 with U22.  I don't think I can test "*" with the games that I have.  The only button not working now that "was" working now from the buttons I can test is 8.  Cybermorph has that 4 digit number input on the planet select screen were I was able to easily test the number buttons.  I have tempest, pitfall, and cybermorph and I don't think they can test buttons * and #.  Buttons C,2,5,0 along with down, 7 & 9 are working now and just button 8 isn't.  I was surprised after getting everything else to work thought i possibly broke my 8 button on the controller while probing around so I tested it on the working console just to verify.  It makes no sense I know.  My brain is wondering if somehow U26 was in fact broken and adding garbage data to the circuit which was why I got a weird in-between voltage on Pin 4 at U18.  Remember my working console functioned about a volt lower at the same pin.  Maybe thats why I am getting odd results.  If this is in fact true moving it to U22 could be causing weird results there now.  I'm no expert and just speculating because it makes no sense.  I'm not going to troubleshoot any more until I replace U22 with the new chips I ordered because if U26 was broken it would make sense I moved the problem to a different set of buttons.  I agree it's not broken in the way I would have expected.

 

I'm not sure if D1 and ED1 directly connect via traces on the circuit board because I was seeing different voltages on the corresponding U26 pins.  That's why I decided to just swap the chips around.  I replaced everything else in the circuit except the BIOS chip and tested continuity and resistance to anything that wasn't a chip.  I know I can break stuff moving things around but I was getting to the point of throwing in the towel anyway.  I trust my soldering skills more than my electronics troubleshooting skills.

5 hours ago, aapuzzo said:

I have tempest, pitfall, and cybermorph and I don't think they can test buttons * and #. 

If you press those buttons together the games should reset to the main menu. See if the reset function is working or not.

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The 68k and Jerry can both be used to read joystick input. The registers themselves are on Jerry, so I guess in a way, Jerry is always the source of the data. I think most the older games use the 68k, and that works fine for most things, but using the DSP helps if you need high sample rates, like for mouse or rotary input, or if you're like me and just write overkill input handling code for a simple menu app.

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On 12/13/2023 at 4:03 AM, Stephen Moss said:

 

 

If the Row strobe for 8 was the issue it should also affect 0, C, 2 & 5, being on the same Row. If it was the pull up resistor or and issue with the input/output to U1in the controller/bad cable then it should also affect 7, 9 & Down being in the same column.

Therefore if neither of those are the case then logically the issue should lie within the controller, either the button itself, Diode D8 or the connection to one of those. as that is the only way it can be non functional in isolation from any other buttons connected to the same Row/Column. 

I would like to thank everybody that helped as the issue with P1 controller inputs is now 100% resolved.  I replaced U22 today with the replacement chip from digikey and all numbers along with the red buttons are working.  I validated the reset function using * & # also works.  I haven't fully tested P2 yet but there were no known issues with it and I was seeing pulses with the oscilloscope when that testing was performed.

 

For anybody that may end up stumbling upon this post my issue was caused by a failed U26 chip and was not the typical problems with U20, U21, U25, or U18.  I obviously had a strange problem because when I swapped U26 with U22 all of the original failed buttons started working with only #8 which was working prior stopped.  I expected something to stop working if U26 was broken obviously if the chip was swapped to another spot on the board but but I wouldn't have expected it to effect only a single button based on the way the Jaguar controllers work.  It seems a failing U26 or U22 can cause weird scenarios so don't rule these chips out in troubleshooting however I would still look at the typical chips U20,21,25, & U18 first.  A failed U26 also seems to be able to cause the scenario where you have no pulse on pin #3.

 

Here is the digikey part number 296-1058-1-ND I used for U22.  It is used in a few spots on the board and is extremely easy to replace with a soldering hot air station and tweezers.  I wouldn't do it without one and they can be acquired cheap.  

 

https://www.digikey.com/en/products/detail/texas-instruments/SN74AC245DWR/276702?s=N4IgTCBcDaKHAEBlAcgdgCwEEDCY0FYARAdQCU4QBdAXyA

 

Once again thanks for all the help.

 

 

Edited by aapuzzo
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