Three Port 10/100 Managed Ethernet Switch with MII
Datasheet
Chapter 8 Serial Management
8.1
Functional Overview
This chapter details the serial management functionality provided by the LAN9313/LAN9313i, which
includes the EEPROM I2C/Microwire master, EEPROM Loader, SPI slave, and I2C slave controllers.
The I2C/Microwire EEPROM controller is an I2C/Microwire master module which interfaces an optional
external EEPROM with the system register bus and the EEPROM Loader. Multiple types
(I2C/Microwire) and sizes of external EEPROMs are supported. Configuration of the EEPROM type
and size are accomplished via the eeprom_type_strap and eeprom_size_strap[1:0] configuration straps
respectively. Various commands are supported for each EEPROM type, allowing for the storage and
retrieval of static data. The I2C interface conforms to the Philips I2C-Bus Specification.
The EEPROM Loader provides the automatic loading of configuration settings from the EEPROM into
the LAN9313/LAN9313i at reset, allowing the LAN9313/LAN9313i to operate unmanaged. The
EEPROM Loader module interfaces to the EEPROM Controller, Ethernet PHYs, and the system CSRs.
The SPI/I2C slave controller can be used for CPU serial management and allows CPU access to all
system CSRs. The SPI slave controller supports single register and multiple register read and write
commands. The I2C slave controller implements the low level I2C slave serial interface (start and stop
condition detection, data bit transmission/reception, and acknowledge generation/reception), handles
the slave command protocol, and performs system register reads and writes. The I2C slave controller
conforms to the Philips I2C-Bus Specification.
8.2
I2C/Microwire Master EEPROM Controller
Based on the configuration strap eeprom_type_strap, the I2C/Microwire EEPROM controller supports
either Microwire or I2C compatible EEPROMs. The I2C/Microwire serial management pins functionality
and characteristics differ dependant on the selected EEPROM type as summarized in Table 8.1.
Table 8.1 I2C/Microwire Master Serial Management Pins Characteristics
EEPROM
TYPE/MODE
EE_SDA/EEDI PIN
EE_SDA
EEDO PIN
NOT USED
EECS PIN
NOT USED
EE_SCL/EECLK PIN
EE_SCL
I2C Master
EEPROM
Mode
Input enabled
(to I2C master)
Input enabled
(used for straps)
Input enabled
(used for straps)
Input enabled
(to I2C master and
used for straps)
Open-drain output
(from I2C master)
Output enabled
(driven low)
Output enabled
(driven low)
eeprom_type_strap
= 1
Open-drain output
(from I2C master)
Pull-down disabled
Microwire
Master
EEPROM
Mode
EEDI
EEDO
EECS
EECLK
Input enabled
(to Microwire master) (used for straps)
Input enabled
Input enabled
(used for straps)
Input enabled
(used for straps)
Output disabled
Output enabled (from
Microwire master)
Output enabled (from
Microwire master)
Output enabled (from
Microwire master)
eeprom_type_strap
= 0
Pull-down enabled
Note: When the EEPROM Loader is running, it has exclusive use of the I2C/Microwire EEPROM
controller. Refer to Section 8.2.4, "EEPROM Loader" for more information.
SMSC LAN9313/LAN9313i
101
Revision 1.2 (04-08-08)
DATASHEET
SMSC [ SMSC CORPORATION ]
