I have been wotking of some 2600 multi-carts and descovered a small error in Bens 4x4 hac wich causes some carts not to work after the hac.
I have descovered what causes them to not work and a fix for it.
I emailed this to Ben but got no responce so I will post the fix here.
On the cart port if you check what Ben calls the "z" pin it goes to ground and also what I call the "1" pin with the fat trace with a 1 next to it also go to ground.
After the 4x4 mod the "1" pin is not connected to ground. This is the problem. Connect Pin "1" to ground as well as the "z" pin and the non working carts are fixed.
What is gong on is that atari carts have 2 ground pins and the cart port had 2 ground pins. Some carts used both and some carts used one or the other pin for ground. So after the hac carts that used only pin one for ground were left ungrounded when inserted this was the problem.
After fixing this problem all of my carts work now.
I hope this helps. Let me know if it fixes all of the nonworking carts of if some are still incompatable.
a way to increase cart compatability with Bens 2600 hac
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no I didn't cut to much. Even Ben has stated that some carts just don't work and I think this is the problem. Check the continuity on your pin 1 after the hac and tell me if it is connected to ground. If not fix it and nonworking carts will work.
I have an unmodded board in my lap and before the mod pin "1 goes to ground.
I have 4 modded boards which all work fine, and after the hac none of them have pin "1" connected to ground.
I use the 4 switchers without the "trublesome little ic" but I am pretty sure that this is a problem on all 4 switchers.
I have an unmodded board in my lap and before the mod pin "1 goes to ground.
I have 4 modded boards which all work fine, and after the hac none of them have pin "1" connected to ground.
I use the 4 switchers without the "trublesome little ic" but I am pretty sure that this is a problem on all 4 switchers.