3 ms·

+++ATH was one of the first abuses of in band signaling I got to enjoy.

• MarkusWandel 5y ago
  Only on a misconfigured or not properly Hayes compatible modem. See other comment.
• krallja 5y ago
  It wouldn’t work on a genuine Hayes modem - those would only listen for commands if there was a pause, +++, another pause, and then the AT command. Hayes’ patent was actually on the pause itself (in-band signaling was already well-known), so the off-brand modems wouldn’t implement it, while still implementing the “Hayes-compatible” command set. Those are the ones you could get to hang up if you could trick the program on the other end into echoing the string “+++ATH”.