SI2493-C-FS Silicon Laboratories Inc, SI2493-C-FS Datasheet - Page 28

• Manufacturer Part Number: SI2493-C-FS
• Description: IC ISOMODEM SYSTEM-SIDE 16SOIC
• Manufacturer: Silicon Laboratories Inc

Specifications of SI2493-C-FS

• Mfg Application Notes: SI2493/57/34/15/04, Appl Note AN93
• Data Format: V.21, V.22, V.23, V.29, V.32, V.34, V.90, V.92, Bell 103, Bell 212A
• Baud Rates: 56k
• Interface: UART
• Voltage - Supply: 3 V ~ 3.6 V
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AN93
The modem has a 48-character buffer, which makes it
possible to enter multiple AT commands on a single
line. The multiple commands can be separated with
spaces or linefeed characters to improve readability.
Neither the AT nor the space (or linefeed characters)
are loaded into the buffer and are not included in the 48
characters. The command must end with a carriage
return character to instruct the modem to process the
command. The modem ignores command lines greater
than 48 characters and reports “ERROR”.
Table 16 shows examples of multiple AT commands on
a single line.
Consecutive U-Registers can be written in a single
command as “AT:Uhh,xxxx,yyyy,zzzz” where hh is the
first
consecutive series. This command writes a value of
28
Command
AT S0=4 M1 X1 <CR> Same as above (spaces do
AT:R2C
ATS0=4M1X1<CR>
ATS2?
AT&$
AT$
ATS0=4<CR>
Table 16. Multiple AT Commands on a
U-Register
ATM1<CR>
ATX1<CR>
Command
Table 15. Command Examples
&G = 017
&D = 001
&H = 000
&P = 000
(Si2457)
M = 000
E = 001
Q = 000
V = 001
X = 004
Y = 000
Result
00A0
043
address
Single Line
the fourth ring. The speaker
is on during dial and hand-
shake only. Blind dialing is
enabled.
not matter).
The modem auto-answers on
Same as above.
Configuration status of basic
AT commands.
Configuration of &AT
commands.
S-Register 2 value—Escape
code character (+).
Value stored in register U2C.
in
the
Comment
Result
three
register
Rev. 0.9
xxxx to Uhh, yyyy to Uhh+1, and zzzz to Uhh+2.
Additional consecutive values may be written up to the
48 character limit.
Caution: Some U-Register addresses are reserved for
internal use and are not available. Consequently, there
are gaps in the addresses of available U-Registers.
Writing to reserved registers can cause unpredictable
results. Be certain the U-Register addresses written
with a consecutive write command have consecutive
addresses. Only one :U or :R command is allowed per
AT command line.
If a command line has multiple commands, there can be
only one :U or :R command, and it must be the last
command
ATS0=3M1X1:U42,0022.
This restriction also applies to all commands beginning
with the “+” character (eg. +VCID).
For example, AT:U42,0022:U43,0010<CR> is an illegal
command and causes unpredictable behavior. Also, \Tn
commands may not be used on the same command line
as a :U or :R command.
The AT command execution time is approximately
300 ms. The host must wait for a response after each
command
commands. The reset recovery time (the time between
a hardware reset or the carriage return of an ATZ
command and the time the next AT command can be
executed) is approximately 300 ms.
Characters must not be sent between the ATDT
command and the protocol message. During this time,
the modem is in a transition between command and
data modes. Any characters sent during this time will
cause the connection attempt to fail.
Blind dialing (dialing without waiting for dial tone) is
enabled by ATX0, ATX1, and ATX3. Whether or not
blind dialing is enabled, use of the W dial modifier
causes the modem to look for a dial tone before dialing
the number string after the W. For example, an AT
command string, “ATX1 DT 9, W123456<CR>”, causes
the modem to dial 9 immediately without detecting a dial
tone but does not dial 123456 until a dial tone is
detected. AT commands and result codes are listed in
Tables 18–22. The default settings are shown in bold.
Table 17. Consecutive U-Register Writes on a
AT:U00,0078,67EF,C4FA
Command
(e.g.,
in
“OK”)
the
Single Line
before
string.
0x0078 written to U00
0x67EF written to U01
0xC4FA written to U02
issuing
For
Result
additional
example,