When I was young, my family had an Atari 800. We had a number of cartridge games. One thing my brother did was to copy cartridges to disk. He would start the computer with the cartridge door open and the switch jammed on, and then stick in the cartridge while the computer was running his program. His first attempts failed. He got it to work by copying the cartridge ROM into RAM, and then saving the copied data instead of saving from the ROM directly.

The Atari disk, which had 128 byte sectors, used the last 2 or 3 bytes to link to the next sector of the file. When saving to disk, the Atari would overwrite the RAM with the links, save the sector, then restore the overwritten bytes. When saving the screen memory, spurious characters would pop up at intervals and then disappear. But that's the reason why saving directly from ROM didn't work.

One of the motivations for copying the cartridges was to be able to cheat by getting extra lives by tweaking some data, or by getting infinite lives by modifying a branch or increment or decrement operation, or something like that.

The Atari also went beep beep beep when reading from the disk, and clunk clunk clunk when writing to the disk.