The game used a codewheel for it copy protection. Electronics Art used many different copy protection forms in the 1980s for it’s Commodore 64 games from Error checking to FAT Tracks on 34/35, to Pirateslayer and then to Codewheels and manual look ups.
After the boot screen and you select
Start Game you get this screen that
ask for your Madden Season Ticket
There was already a print out of the codewheel, BUT it’s pretty confusing look at this: John Madden Football