Hayes H08-15357-A Reference Manual

AT V.250 Commands for V.92

(1) “AT+MS = V92” - command to enable V.92 mode. All new features are available only if this command is

enabled. To disable V.92 use “AT+MS=V90”. To query the mode of operation, use “AT+MS?”.

(2) “AT+DCS = 1, 1” – command to enable/disable V.44 data compression. The first parameter is for V.42bis and the

second parameter is for V.44. An “AT+DCS = 1, 0”, will disable V.44 data compression. V.44 data compression
will work only to a V.92 server. To test V.44 between two modems in V.34 mode, use the “AT+DCS = 1, 2”
command.

(3) “AT+PCW = <call waiting>” – Call Waiting Enable command. This command controls the action to be taken

upon detection of call waiting tone in V.92 mode.
<call waiting> = 0, (default) Toggle V.24 Circuit 125, (RI lead) and collect Caller ID if enabled by +VCID
1 , Hang Up
2 , Ignore V.92 call waiting

(4) “AT+PQC = <quick connect>” – This command controls V.92 shortened Phase1 and Phase 2 startup procedures.

<quick connect> = 0, enable short phase 1 and short phase 2 ( default )
= 1, enable short phase 1
= 2, enable short phase 2
= 3, disable short phase 1 and short phase 2

(5) “AT+PMH = <value>” – command to enable modem on hold feature to a V.92 server.

<value> = 0, (default) enables initiation of V.92 modem on hold.

= 1, disable initiation of V.92 modem on hold

(6) “AT+PMHR” – initiate modem on hold. The modem returns ERROR if modem on hold is not enabled or if the

modem is in a idle condition. The modem will respond with the following response :
+PMHR : <value> = 0 , deny V.92 modem on hold request

= 1 , grant modem on hold with 10 second timeout

= 2 , grant modem on hold with 20 second timeout
= 3 , grant modem on hold with 30 second timeout
= 4 , grant modem on hold with 40 second timeout
= 5 , grant modem on hold with 1 minute timeout
= 6 , grant modem on hold with 2 minute timeout
= 7 , grant modem on hold with 3 minute timeout
= 8 , grant modem on hold with 4 minute timeout
= 9 , grant modem on hold with 6 minute timeout
= 10 , grant modem on hold with 8 minute timeout
= 11 , grant modem on hold with 12 minute timeout
= 12 , grant modem on hold with 16 minute timeout
= 13 , grant modem on hold with indefinite timeout

(6) “AT+PIG = 1” – command to enable PCM upstream to a V.92 server (default). To disable PCM upstream,

“AT+PIG = 0”. PCM upstream is not supported in this release.

(7) “AT+PMHF” – V.92 Modem on Hold Hook Flash command. This command causes the modem to go on-hook for

½ second and the n return off-hook.