Specifications

Si2457/Si2434/Si2415
28 Rev. 0.91
Extended AT Commands
The extended AT commands are supported by the Si2457/34/15 and are described in Tables 10 through 12.
Table 10. Extended AT& Command Set (Command Defaults in Bold)
Command Action
&$
Display AT& current settings.
&D0
ESC (pin 22) is not used
&D1
ESC (pin 22) escapes to command mode from data mode if also enabled by HES U70, bit 15.
&D2
ESC (pin 22) assertion during a modem connection causes the modem to go on-hook and return to
command mode.
&D3
ESC (pin 22) assertion causes ATZ command (reset and return OK result code).
&F
Restore factory default settings.
&Gn
Line connection rate limit—This command sets an upper limit on the line speed that the Si2457/34/
15 can connect. Note that the &Hn commands may limit the line speed as well (&Gn not used for
&H0 or &H1). Not all modulations support rates given by &G. Any improper setting will be ignored.
&G3
1200 bps max
&G4
2400 bps max
&G5
4.8 kbps max
&G6
7.2 kbps max
&G7
9.6 kbps max
&G8
12 kbps max
&G9
14.4 kbps max (default for Si2415)
&G10
16.8 kbps max
&G11
19.2 kbps max
&G12
21.6 kbps max
&G13
24 kbps max
&G14
26.4 kbps max
&G15
28.8 kbps max
&G16
31.2 kbps max
&G17
33.6 kbps max (default for Si2457 and Si2434)
&Hn
Switched network handshake mode—&Hn commands must be on a separate command line from
ATD, ATA, or ATO commands.
&H0
V.90 with automatic fallback (56 kbps to 300 bps) (default for Si2457)
&H1
V.90 only (56 kbps to 28 kbps)
&H2
V.34 with automatic fallback (33.6 kbps to 300 bps) (default for Si2434)
&H3
V.34 only (33.6 kbps to 2400 bps)