EMC6D103-CK SMSC [SMSC Corporation], EMC6D103-CK Datasheet - Page 20

• Manufacturer Part Number: EMC6D103-CK
• Description: FAN CONTROL DEVICE WITH HIGH FREQUENCY PWM
• Manufacturer: SMSC [SMSC Corporation]

Revision 0.4 (04-04-05)
5.4
5.4.1
5.5
5.6
FIELD
FIELD:
Bits
Bits:
START
START
Read Byte
The Read Byte protocol is used to read data from the registers. The data will only be read if the
protocol shown in
protocol.
Registers that are accessed with an invalid protocol will not be updated. A register will only be updated
following a valid protocol. The only valid protocols are the Write Byte and Read Byte protocols, which
are described above.
The EMC6D103 device responds to three SMBus slave addresses:
1. The SMBus slave address that supports the valid protocols defined in the previous sections is
2. SMBus Alert Response (0001 100). The SMBus will only respond to the SMBus Alert Response
Attempting to communicate with the Hardware Monitor Block over SMBus with an invalid slave
address, or invalid protocol will result in no response, and the SMBus Slave Interface will return to the
idle state.
The only valid registers that are accessible by the SMBus slave address are the registers defined in
the Registers Section. See
Undefined Registers
Reads to undefined registers return 00h. Writes to undefined registers have no effect and return no
error.
The EMC6D103 will not respond to a general call address of 0000_000.
The EMC6D103 supports the slave device timeout as per the SMBus Specification, v2.0.
1
Invalid Protocol Response Behavior
General Call Address Response
Slave Device Time-Out
1
determined by the level on the Address Select and Address Enable pins as shown in
"Slave Address," on page
Address if the SMBus Alert Response interrupt was generated to request a response from the Host.
The SMBus Alert Response is defined in
page
SLAVE
ADDR
SLAVE ADDR
7
21.
7
WR
1
Table 5.3
Table 5.2 SMBus Write Byte Protocol
ACK
Table 5.3 SMBus Read Byte Protocol
Fan Control Device with High Frequency PWM Support and Hardware Monitoring Features
1
WR
Section 5.4.1, "Undefined Registers"
is performed correctly. Only one byte is transferred at time for a Read Byte
1
ADDR
REG.
18.
8
ACK
DATASHEET
1
ACK
1
20
REG. ADDR
START
1
Section 5.10, "SMBus Alert Response Address," on
8
SLAVE
ADDR
7
ACK
1
RD
1
for response to undefined registers.
REG. DATA
ACK
1
8
DATA
REG.
8
SMSC EMC6D103
ACK
NACK
1
1
Section 5.1,
Datasheet
STOP
STOP
1
1