I do what I can to help and it is no big deal. People have helped me too.

I had downloaded that page long ago, it turns out. I love the ASCII timing
diagrams.

There is a funny mode story. In the 90s, when we had dial-ups, a friend changed
his password to the name of his newly-born daughter. He would dial in and then
the connection would drop. Then he realized that as the password was being
negotiated the modem would hangup because the name started with the leters:
"ath". This took him days to find, and I thought it was weird that the modem
still thought it was negotiating commands after it had established connection.
No, I am not sorry that those days are over!