CH1794A Cermetek Microelectronics, CH1794A Datasheet - Page 10

• Manufacturer Part Number: CH1794A
• Manufacturer: Cermetek Microelectronics

Specifications of CH1794A

• Lead Free Status / RoHS Status: Not Compliant

Cermetek Microelectronics, Inc.
AT COMMAND APPLICATIONS
Dialing a Phone Number. The Dial command takes
the form Dn, where n is a string of characters. In the
simplest form, n will be only the digits of the phone
number to be dialed.
Example:
Enter:
Result:
In response to this command, the HS Modem goes
Off-Hook and dials the telephone number “123-4567”
and then waits for a carrier from the distant modem. If
no carrier is detected within a given time (the default
time is 30 seconds), the HS Modem automatically
releases the line and sends a NO CARRIER result
code. If a carrier is detected, the HS Modem gives a
CONNECT result code and goes on-line, permitting
communication with the distant modem.
The Dial command may also be issued without a
telephone number. ATD causes the modem to pick up
the telephone a line without dialing a number.
Pause During Dialing. When placing a call from an
office with a telephone connected to a PBX, it may be
necessary to dial an access code (usually the digit 9)
to get an outside line.
telephone number commands the modem to pause for
a specific length of time. The factory default pause
time is 2 seconds.
Example:
Enter:
Result:
Multiple commas may be used for a greater delay
time.
Touch Tone and Pulse Dialing. The modem can use
DTMF (touch-tones) T, or dial pulses P when dialing a
telephone number.
specify which type to use, the modem defaults to the
type last specified. The power-on default value is T.
2007 Cermetek Microelectronics, Inc.
Operation
CH179XAR-L/CH2056AR-L on a standard PSTN
line will damage the CH179XA-L/CH2056A-L and
CH179XAR-L/CH2056AR-L and void its warranty.
Further, operation of the CH179XA-L/CH2056A-L
and CH179XAR-L/CH2056AR-L on a dry line
without using proper current limiting circuitry as
outlined in Cermetek Application Note # 126 may
cause damage to the CH179XA-L/CH2056A-L and
CH179XAR-L/CH2056AR-L and will also void its
warranty.
Dial Number.
ATD1234567<CR>
Modem goes Off-Hook, dials
Dial 9, pause, dial number.
ATDT9, T1234567<CR>
Modem goes Off-Hook, dials
of
the
WARNING
If the dial command does not
CH179XA-L/CH2056A-L
Inserting a comma in the
and
Page 10
Example:
Enter:
Result:
Redial Last Number. Use A/, the repeat command,
to redial the last telephone number dialed when a busy
signal is received.
Go Off-Hook and Return to Command State. The
modem can be forced to reenter the command state
after going off-hook by issuing the ATDT command
with a semi-colon.
modem with an independent DTMF tone generator.
Example:
Enter:
Result:
Automatic Answering.
Answer:
1. Enter: ATS0=0<CR>
2. Enter: ATS0=1-255<CR> Modem will answer on 1
Note that when S0 is set to 0, the HS Modem will not
auto-answer.
V.22 Fast Connect. The HS modem family supports
non-standard V.22 fast connect protocols.
feature reduces the connect time to 3-4 seconds.
However, to utilize the fast connect protocol, this
protocol must be supported by both modems. Further,
the DCE speed must be set to 1200 baud (i.e., V.22).
To setup the HS modem product to connect utilizing
Fast Connect, execute the following commands:
Enter: AT+MS=V22,0,300,1200,300,1200<CR>
Result: OK<CR><LF>
Enter: $F2<CR>
Result: OK<CR><LF>
This forces the modem to communicate using the V.22
protocol and to attempt to connect using Fast Connect.
If Fast Connect is not supported by the other modem,
the modem will connect using the standard V.22
protocol.
Caller ID (CID). The “C” version of the HS Family
supports Caller ID.
reporting and presentation of the data provided by the
PSTN Caller ID services. Data is presented to the
DTE between the first and the second ring indication.
This command affects the data format for incoming
calls as the call is being received.
CH179XA/2056A High Speed Family of Ultra Small Modems
Pulse dial 9, pause, touch-tone dial
number.
ATDP9, T1234567<CR>
OK<CR><LF>
Touch-tone dial 9, pause, go off-hook,
return for additional AT commands.
ATDT9, T;<CR>
OK<CR><LF>
Document No. 607-0020 Revision B (01/07)
This is useful when using the
The +VCID command controls
Some examples of Auto
Modem will not auto-
answer
to 254 rings
This