EMC2301 Standard Microsystems Corp., EMC2301 Datasheet - Page 14

• Manufacturer Part Number: EMC2301
• Description: Rpm-based Pwm Fan Controller
• Manufacturer: Standard Microsystems Corp.

START
Revision 1.2 (03-22-10)
1 -> 0
3.2.2
3.2.3
3.2.4
3.2.5
REGISTER
START
START
START
DATA
1 -> 0
1 -> 0
1 ->0
XXh
YYYY_YYYb
ADDRESS
SLAVE
Read Byte
The Read Byte protocol is used to read one byte of data from the registers as shown in
Send Byte
The Send Byte protocol is used to set the internal address register pointer to the correct address
location. No data is transferred during the Send Byte protocol as shown in
Receive Byte
The Receive Byte protocol is used to read data from a register when the internal register address
pointer is known to be at the right location (e.g. set via Send Byte). This is used for consecutive reads
of the same register as shown in
Block Write Protocol
The Block Write is used to write multiple data bytes to a group of contiguous registers as shown in
Table
YYYY_YYYb
ADDRESS
SLAVE
YYYY_YYYb
YYYY_YYYb
3.6. It is an extension of the Write Byte Protocol.
ADDRESS
ADDRESS
ACK
WR
SLAVE
SLAVE
0
0
ACK
0
REGISTER
DATA
Register
Address
XXh
WR
0
XXh
Table 3.5 Receive Byte Protocol
Table 3.6 Block Write Protocol
WR
RD
Table 3.3 Read Byte Protocol
Table 3.4 Send Byte Protocol
0
1
ACK
Table
ACK
ACK
DATASHEET
0
0
0
3.5.
START
0 -> 1
ACK
ACK
14
0
0
REGISTER
ADDRESS
XXh
. . .
. . .
YYYY_YYYb
Address
Slave
REGISTER DATA
REGISTER
ADDRESS
XXh
XXh
REGISTER
RD
DATA
1
ACK
XXh
0
ACK
0
RPM-Based PWM Fan Controller
Table
NACK
REGISTER
Register
ACK
Data
XXh
0
1
DATA
ACK
XXh
3.4.
0
SMSC EMC2301
NACK
Table
1
STOP
0 -> 1
STOP
0 -> 1
Datasheet
STOP
0 -> 1
ACK
3.3.
0
STOP
0 -> 1