3Com U.S. Robotics 56K Voice User Manual page 60

Hn Controls ON/OFF hook
H0 Hangs up (goes on hook)
H1 Goes off hook
In Displays the following information
I0 Four-digit product code
I1 Results of ROM checksum
I2 Results of RAM checksum
I3 Product type
I4 Current modem settings
I5 Nonvolatile memory (NVRAM) settings
I6 Link diagnostics
I7 Product configuration
I9 Plug and Play information
I11 Extended link diagnostics
Ln Controls speaker volume (internals only)
L0 Low volume
L1 Low volume
L2 Medium volume
L3 High volume
Mn Operates speaker
M0 Speaker always OFF
M1 Speaker ON until CONNECT
M2 Speaker always ON
M3 Speaker ON after dial, until CONNECT
On Returns online
O0 Returns online
O1 Returns online and retrains
P Sets pulse dial (for phone lines that do not support
touch-tone dialing)
Qn Displays/suppresses result codes
Q0 Displays result codes
Q1 Quiet mode; no result codes
Q2 Displays result codes only in Originate mode
54 56K Voice Faxmodem Internal - User's Guide
Technical Reference