si2401 Silicon Laboratories, si2401 Datasheet - Page 15

• Manufacturer Part Number: si2401
• Description: V.22bis Isomodem With Integrated Global Daa
• Manufacturer: Silicon Laboratories

4.3. Low Power Modes
The Si2401 has three low-power modes:
China - People's Republic
DSP Powerdown. The DSP processor can be
powered down by setting register
SEB[3] (PDDE) = 1.
In this mode, the serial interface still functions, and
the modem detects ringing and intrusion. However,
no modem modes or tone detection features
function.
Wake-Up-On-Ring. By issuing the ATz command,
the Si2401 goes into a low-power mode where both
the microcontroller and DSP are powered down.
Only an incoming ring, a low TXD signal, or a total
reset will power up the chip again. Return from
wake-on-ring triggers the INT pin if S09[6]
Si2401 Register
Belgium (EU)
Austria (EU)
Costa Rica
Caribbean
Argentina
Bahamas
Colombia
Bermuda
Country
Australia
Armenia
Bulgaria
Bahrain
Canada
Belarus
Algeria
Brunei
Brazil
Chile
OHS
10
00
00
01
10
00
10
00
10
00
00
00
10
00
00
00
00
00
00
Table 10. Country-Specific Register Settings
ILIM
1
0
0
0
1
0
1
0
1
0
0
0
1
0
0
0
0
0
0
SF5
RZ
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Rev. 1.0
4.4. Global DAA Operation
The Si2401 chipset contains an integrated silicon direct
access arrangement (silicon DAA) that provides a
programmable line interface to meet international
telephone line requirements. Table 10 gives the DAA
register settings required to meet various country PTT
standards.
RT
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
(WOR) = 1 (WOR = 0
Total Powerdown. Setting SF1[5] = 1 and SF1[6] = 1
places the Si2401 into a total powerdown mode. All
logic is powered down including the crystal oscillator
and clock-out pin. Only a hardware reset can restart
the Si2401.
MINI[1:0] DCV[1:0] ACT[3:0]
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
10
00
00
00
SF6
10
10
10
01
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
b
by default).
0011
0000
0000
0000
0011
0000
0000
0000
0000
0011
0000
0000
0000
0000
0000
0000
0011
0011
0011
ATSF5=28SF6=23
ATSF5=00SF6=20
ATSF5=00SF6=20
ATSF5=10SF6=93
ATSF5=28SF6=23
ATSF5=00SF6=20
ATSF5=28SF6=23
ATSF5=00SF6=20
ATSF5=28SF6=23
ATSF5=00SF6=20
ATSF5=00SF6=20
ATSF5=00SF6=20
ATSF5=28SF6=23
ATSF5=00SF6=20
ATSF5=00SF6=20
ATSF5=00SF6=20
ATSF5=00SF6=20
ATSF5=00SF6=20
ATSF5=00SF6=20
AT Command
Si2401
String
15