Never enough repair logs here - this one was fun.
I never played this back in the day - a little research showed that while the trackball had been used in a couple of games prior to Atari Football - this machine made trackballs popular.
Got a request from an arcade I've done some repair for in the past. Could I fix a couple of Atari Football boards? After taking a look at the schematics, I couldn't see why not..
The way I test boards is to use my Test Bench and Adapters


This one was a bit different than most. Power was simple - but took a little planning. Football is pre-ARI/II days and the board does its own voltage regulation using AC inputs. I'm using the 10.3vdc and 22vdc connections from the bench supply and that passes through the regulator diodes. It also uses 2 trackballs - I just need to test functionality vs have a 2 player game running on the bench. I made a P1 and P2 connector for the trackballs and can test both sides by just swapping the inline connections to my controller. One other item was the original control panels used LEDs to show you what play you are choosing. I had made one of these little LED displays for Lunar Lander which shows your selection the same way. As luck would have it, Football is common anode and Lunar Lander is common cathode - so now I have two LED displays for bench adapters. If there is ever another game with LEDs on the CP - I'm ready for it! I didn't need to make the LED display, it's just fun. I could test the game board directly if I wanted too.. The adapters take a 2-3 hours to build and test - but after that testing any board takes a few seconds to connect and you know the setup is 100%.
Board #1

Both boards came in and are in really nice shape for the most part. Once I got the board powered and voltages verified I worked on a FPGA Tester config. The memory map is relatively simple on Football. I can also see how some of Atari's later designs evolved from this one (and probably games before it). From what I can tell, Centipede and Warlords use a similar (identical?) video memory layout. I can also understand how the ARI and ARII came to life. The voltage regulator and power resistor get hot - the resistor gets burn your finger hot.. After running it a few hours on the bench while in the shop, there are no ill effects. That said - if Football doesn't have a cooling fan - I recommend it unless you bypass the on-board regulation and use different power.
First item during testing was the work ram was not being accessed properly

/PFWR not functioning.

Working backwards, the 7432@B4 was doing its job, the /WRITE was not working.

7400@C3 - not working correctly. Replaced it and we can now write to the RAM. Moving on to testing ROM - @M1 wasn't reading. Quick test with known good ROM - same thing. Checked and the select PIN20 was not toggling.

Working backwards, 7432@B4 had no output on pin8. Replacing it corrected the ROM read.

Board works!
I never played this back in the day - a little research showed that while the trackball had been used in a couple of games prior to Atari Football - this machine made trackballs popular.
Got a request from an arcade I've done some repair for in the past. Could I fix a couple of Atari Football boards? After taking a look at the schematics, I couldn't see why not..
The way I test boards is to use my Test Bench and Adapters


This one was a bit different than most. Power was simple - but took a little planning. Football is pre-ARI/II days and the board does its own voltage regulation using AC inputs. I'm using the 10.3vdc and 22vdc connections from the bench supply and that passes through the regulator diodes. It also uses 2 trackballs - I just need to test functionality vs have a 2 player game running on the bench. I made a P1 and P2 connector for the trackballs and can test both sides by just swapping the inline connections to my controller. One other item was the original control panels used LEDs to show you what play you are choosing. I had made one of these little LED displays for Lunar Lander which shows your selection the same way. As luck would have it, Football is common anode and Lunar Lander is common cathode - so now I have two LED displays for bench adapters. If there is ever another game with LEDs on the CP - I'm ready for it! I didn't need to make the LED display, it's just fun. I could test the game board directly if I wanted too.. The adapters take a 2-3 hours to build and test - but after that testing any board takes a few seconds to connect and you know the setup is 100%.
Board #1

Both boards came in and are in really nice shape for the most part. Once I got the board powered and voltages verified I worked on a FPGA Tester config. The memory map is relatively simple on Football. I can also see how some of Atari's later designs evolved from this one (and probably games before it). From what I can tell, Centipede and Warlords use a similar (identical?) video memory layout. I can also understand how the ARI and ARII came to life. The voltage regulator and power resistor get hot - the resistor gets burn your finger hot.. After running it a few hours on the bench while in the shop, there are no ill effects. That said - if Football doesn't have a cooling fan - I recommend it unless you bypass the on-board regulation and use different power.
First item during testing was the work ram was not being accessed properly

/PFWR not functioning.

Working backwards, the 7432@B4 was doing its job, the /WRITE was not working.

7400@C3 - not working correctly. Replaced it and we can now write to the RAM. Moving on to testing ROM - @M1 wasn't reading. Quick test with known good ROM - same thing. Checked and the select PIN20 was not toggling.

Working backwards, 7432@B4 had no output on pin8. Replacing it corrected the ROM read.

Board works!




