Alright, put some fresh ROMs and, just as suspected, nothing changed.
I started investigating further and I *think* I've found what's wrong: There's a 74LS04 which is a hex inverter which... doesn't invert, LOL.
Before goofing, please, can you confirm that all this thing does is taking an input and spitting it inverted on its output?
http://www.ti.com/lit/ds/symlink/sn5404.pdf
Which means that if I find with my logic probe a logic value of LOW on 1A I should get HIGH on 1Y (and viceversa)?
EDIT: YES!!!! THAT WAS THE ISSUE!! I've removed the faulty IC and bridged the input and output, simulating what the issue was with the faulty LS04 and I had the same graphic issues!
I think I'm close to solving this problem, I've ordered a new LS04, now I just have to wait.
I started investigating further and I *think* I've found what's wrong: There's a 74LS04 which is a hex inverter which... doesn't invert, LOL.
Before goofing, please, can you confirm that all this thing does is taking an input and spitting it inverted on its output?
http://www.ti.com/lit/ds/symlink/sn5404.pdf
Which means that if I find with my logic probe a logic value of LOW on 1A I should get HIGH on 1Y (and viceversa)?
EDIT: YES!!!! THAT WAS THE ISSUE!! I've removed the faulty IC and bridged the input and output, simulating what the issue was with the faulty LS04 and I had the same graphic issues!
I think I'm close to solving this problem, I've ordered a new LS04, now I just have to wait.
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