Thank you very much.
No, I'm not Roberto Lavarone, he wrote the source but he's another person.
And now a little bit of history...
When I manually dumped that eprom 40 years ago I wrote it on a piece of paper, then the original 2708 eprom was broken.
After many years I recreated the eprom starting from the written paper, but thanks to my bad writing skills
I misread a "CD" and programmed a "C0" in the file (look at the following image: it's the last "CD 78 80").
I never noticed that bug because it's very hard to happen: infact that is part of the error checking routine related to writing to cassette tape, but it can't almost never happen because it could be fired only in case of a hardware communication error between the CPU and the UART, and that's almost impossible.
Now I found a original listing of that eprom, so I noticed the bug. It's never too late...