Use Procedure 19 for an escape sequence for Hayes KBD. When
configured for Hayes KBD, the MADO operation consists of two states:
the command state and the on–line (or transparent) data state. After
the call is established, the MADO enters the on–line state. To return
from the on–line state to the command state, use the escape code
sequence in Procedure 19.
Procedure 19
Escape Hayes KBD
1
Response: Wait at least one second after previous entry.
2
Type:
+++
Response: Space each plus-sign entry less than one second
apart.
3
Response: Wait at least one second before next entry.
Meridian SL-100 M2000 Digital Telephone Reference Manual
Keyboard dialing 25