SI2404 SILABS [Silicon Laboratories], SI2404 Datasheet - Page 20

• Manufacturer Part Number: SI2404
• Description: V.90, V.34, V.32BIS, V.22BIS ISOMODEM WITH GLOBAL DAA
• Manufacturer: SILABS [Silicon Laboratories]

Si2457/34/15/04
4.18. EEPROM Interface
(24-Pin Version Only)
The Si2457/34/15/04 supports an optional serial
peripheral interface (SPI) bus serial EEPROM Mode 3
with a 16-bit (8–64 kbit range) address. Upon powerup,
if a pulldown resistor ≤10 kΩ is placed between D6
(Si2457, pin 4) and GND (see Table 8), the ISOmodem
attempts to detect an EEPROM. The EEPROM is
intended first for setting custom defaults, second for
automatically loading firmware upgrades, and third to
allow for user-defined AT command macros for use in
custom AT commands or country codes. See “AN93:
Modem Designer’s Guide” for complete details.
4.19. AT Commands
At powerup, the Si2457/34/15/04 is in the AT command
mode. In command mode, the modem monitors the
input (serial or parallel) checking constantly for a valid
command (AT commands are described in Table 10.)
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Rev. 1.0