![](http://datasheet.mmic.net.cn/Silicon-Laboratories-Inc/SI2494-A-GM_datasheet_102086/SI2494-A-GM_29.png)
Si2494/39
Rev. 1.0
29
Vn
V0
Numeric result codes.
V1
Verbal result codes
Xn
Call Progress Monitor (CPM)—This command controls which CPM signals are monitored
X0
Basic results; disable CPM—Blind dial (does not wait for dial tone). CONNECT message
does not include speed.
X1
Extended results; disable CPM—Blind dial. CONNECT message includes speed.
X2
Extended results and detect dial tone only—Add dial tone detection to X1 mode. Does not
blind dial.
X3
Extended results and detect busy only—Add busy tone detection to X1 mode.
X4
Extended results, full CPM—Full CPM enabled, CONNECT message includes speed.
X5
Extended results—Full CPM enabled including ringback detection. Adds ringback detection
to X4 mode.
Yn
Long space disconnect—Modem hangs up after 1.5 seconds or more of continuous space
while on-line.
Y0
Disable.
Y1
Enable.
Z
Hard Reset—This command is functionally equivalent to pulsing the RESET pin low. (See
:E
Read from serial EEPROM.
:I
Interrupt Read—This command causes the ISOmodem to report the lower 8 bits of the
interrupt register I/O Control 0 (U70). The CID, OCD, PPD, and RI bits also are cleared, and
the INT pin (INT bit in parallel mode) is deactivated on this read.
:M
Write to serial EEPROM.
:P
Program RAM Write—This command is used to upload firmware supplied by Silicon Labs to
the Si2494/39. The format for this command is AT:Paaaa,xxxx,yyyy,.... where aaaa is the first
address in hexadecimal and xxxx,yyyy,.... is data in hexadecimal. Only one :P command is
allowed per AT command line. No other commands can be concatenated in the :P command
line. This command is only for use with special files provided by Silicon Laboratories. Do not
attempt to use this command for any other purpose.
:R
User-Access Register Read—This command allows the user to read from the user-access
where:
aa = user-access address in hexadecimal.
The “AT:R” command causes all the U- registers to be displayed.
:U
User-Access Register Write—This command allows the user to write to the 16-bit user-
access registers. (See page
page 54.) The format is “AT:Uaa,xxxx,yyyy,zzzz,...” where
aa = user-access address in hexadecimal.
xxxx = Data in hexadecimal to be written to location aa.
yyyy = Data in hexadecimal to be written to location (aa + 1).
zzzz = Data in hexadecimal to be written to location (aa + 2).
etc.
Table 10. Basic AT Command Set (Command Defaults in Bold) (Continued)
Command
Action