P - Set Pulse Dial Default; A - Answer; H - Disconnect (Hang-Up) - Conexant H08-15355F Reference Manual

3.2.3.3 P - Set Pulse Dial Default

This command forces pulse dialing until the next T dial modifier or T command is received. Sets S14 bit 5.
As soon as a dial command is executed which explicitly specifies the dialing mode for that particular call (e.g., ATDT..), this
command is overridden so that all future dialing will be tone dialed. (See T command.)
This command may not be permitted in some countries.

3.2.3.4 A - Answer

The modem will go off-hook and will attempt to answer an incoming call if correct conditions are met. Upon successful
completion of answer handshake, the modem will go on-line in answer mode. This command may be affected by the state of
Line Current Sense, if enabled. (Most countries do not require Line Current Sense.) Operation is also dependent upon
+FCLASS command and country-specific requirements.
If +FCLASS=0 is selected, the modem will enter the connect state after exchanging carrier with the remote modem. If no
carrier is detected within a period specified in register S7, the modem will hang up. Any character entered during the connect
sequence will abort the connection attempt.
If +FCLASS=1.0 is selected, the modem will go off-hook in V.21 answer mode. It will generate the V.21 2100 Hz answer tone
for 3 ± 0.5 seconds. Following a delay of 70 ms, it will proceed as if the +FTH=3 command were issued. At any stage up to
(but excluding) the +FTH=3 command state, any character will abort the communication. (See the description of the +FTH
command for details.)

3.2.3.5 H - Disconnect (Hang-Up)

This command initiates a hang up sequence. This command may not be available for some countries due to PTT restrictions.
Syntax
H[<value>]
Defined Values
<value> Decimal number corresponding to the selected option.
Result Codes
OK <value> = 0 or 1.
ERROR Otherwise.
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Command Reference Manual
0 The modem will release the line if the modem is currently on-line.
1 If on-hook, the modem will go off-hook and remain in command mode.
Conexant
3-19