FDC37B782-NS Standard Microsystems (SMSC), FDC37B782-NS Datasheet - Page 167

• Manufacturer Part Number: FDC37B782-NS
• Manufacturer: Standard Microsystems (SMSC)

Specifications of FDC37B782-NS

• Lead Free Status / RoHS Status: Supplier Unconfirmed

Entering the Configuration State
The device enters the Configuration State when
the following Config Key is successfully written to
the CONFIG PORT.
Config Key = < 0x55>
When in configuration mode, all logical devices
function
configuration mode has no effect on the devices.
Exiting the Configuration State
The device exits the Configuration State when the
following Config Key is successfully written to the
CONFIG PORT.
Config Key = < 0xAA>
CONFIGURATION SEQUENCE
To program the configuration registers, the
following sequence must be followed:
1. Enter Configuration Mode
2. Configure the Configuration Registers
3. Exit Configuration Mode.
Enter Configuration Mode
To place the chip into the Configuration State the
Config Key is sent to the chip's CONFIG PORT.
The config key consists of a write of 0x55 data to
the CONFIG PORT.
received correctly the chip enters into the
Configuration State (The auto Config ports are
enabled).
properly.
Once the initiation key is
Entering
and
exiting
149
Configuration Mode
The system sets the logical device information
and activates desired logical devices through the
INDEX and DATA ports. In configuration mode,
the INDEX PORT is located at the CONFIG PORT
address and the DATA PORT is at INDEX PORT
address + 1.
The desired configuration registers are accessed
in two steps:
a. Write the index of the Logical Device Number
Configuration Register (i.e., 0x07) to the INDEX
PORT and then write the number of the desired
logical device to the DATA PORT.
b. Write the address of the desired configuration
register within the logical device to the INDEX
PORT and then write or read the configuration
register through the DATA PORT.
Note: if accessing the Global Configuration
Registers, step (a) is not required.
Exit Configuration Mode
To exit the Configuration State the system writes
0xAA to the CONFIG PORT. The chip returns to
the RUN State.
Note: Only two states are defined (Run and
Configuration).
always be ready to enter the Configuration State.
In the Run State the chip will