FDC37C672QFP SMSC Corporation, FDC37C672QFP Datasheet - Page 122

• Manufacturer Part Number: FDC37C672QFP
• Description: ENHANCED SUPER I/O CONTROLLER WITH FAST IR
• Manufacturer: SMSC Corporation

19.1.3 Exiting the Configuration State
19.2
19.2.1 Enter Configuration Mode
19.2.2 Configuration Mode
Note:
19.2.3 Exit Configuration Mode
Note:
SMSC FDC37C672
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.
2.
3.
To place the chip into the Configuration State the Config Key is sent to the chip's CONFIG PORT. The
config key consists of 0x55 written to the CONFIG PORT. Once the configuration key is received correctly
the chip enters into the Configuration State. (The auto Config ports are enabled.)
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.
b.
If accessing the Global Configuration Registers, step (a) is not required.
To exit the Configuration State the system writes 0xAA to the CONFIG PORT. The chip returns to the
RUN State.
Only two states are defined (Run and Configuration). In the Run State the chip will always be ready to
enter the Configuration State.
Enter Configuration Mode
Configure the Configuration Registers
Exit Configuration Mode.
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
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.
DATASHEET
Page 122
Enhanced Super I/O Controller with Fast IR
Rev. 10-29-03
Datasheet