Intel MD566X - Manual (Page 44)

56K V.92 Data, Fax, and Voice Chipset
44 Intel Confidential Programmer’s Guide
En 1
Command Mode Echo: This command selects whether the modem echoes
AT commands back to the host in either online or off-line command mode.
n = 0 Echo disabled
n = 1** Echo enabled
Fn 1
Online Echo: Usually this command selects whether the modem echoes
data back to the host during online data mode. This chipset does not support
online data mode echo.
n = 0 Echo enabled (returns an error message)
n = 1** Echo disabled
Hn 0
Switch Hook Control: This command controls the telephone line relay
(OHREL*) and causes the modem to either hang up or pick up the telephone
line.
n = 0** Hang up telephone line (go on-hook)
n = 1 Pick up telephone line (go off-hook)
Table 3-4. Data Mode Command Descriptions (Continued)