emc2305 Standard Microsystems Corp., emc2305 Datasheet - Page 16

• Manufacturer Part Number: emc2305
• Description: Multiple Rpm-based Pwm Fan Controller For Five Fans
• Manufacturer: Standard Microsystems Corp.

START
1->0
ACK
0
YYYY_YYYb
REGISTER
ADDRESS
SLAVE
Revision 1.2 (03-22-10)
DATA
3.2.4
3.2.5
3.2.6
3.2.7
XXh
REGISTER
START
START
DATA
1 ->0
1 -> 0
XXh
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
Block Read Protocol
The Block Read is used to read multiple data bytes from a group of contiguous registers as shown in
Table
Alert Response Address
The ALERT# output can be used as a processor interrupt or as an SMBus Alert when configured to
operate as an interrupt.
When it detects that the ALERT# pin is asserted, the host will send the Alert Response Address (ARA)
to the general address of 0001_100xb. All devices with active interrupts will respond with their client
address as shown in
ACK
WR
0
0
YYYY_YYYb
ADDRESS
SLAVE
YYYY_YYYb
3.7. It is an extension of the Write Byte Protocol.
3.8. It is an extension of the Read Byte Protocol.
ADDRESS
ACK
SLAVE
0
REGISTER
DATA
XXh
ACK
0
REGISTER
DATA
Table
XXh
WR
0
REGISTER
ADDRESS
Table 3.6 Receive Byte Protocol
Table 3.7 Block Write Protocol
Table 3.8 Block Read Protocol
3.9.
RD
XXh
1
ACK
0
Table
ACK
ACK
DATASHEET
0
0
3.6.
REGISTER
ACK
DATA
16
XXh
ACK
0
0
REGISTER
ADDRESS
XXh
. . .
. . .
REGISTER DATA
Multiple RPM-Based PWM Fan Controller for Five Fans
START
1 ->0
ACK
0
XXh
REGISTER
DATA
YYYY_YYYb
ACK
XXh
0
ADDRESS
SLAVE
. . .
. . .
NACK
REGISTER
1
DATA
ACK
XXh
REGISTER
0
DATA
XXh
RD
1
SMSC EMC2305
STOP
0 -> 1
Datasheet
STOP
0 -> 1
ACK
NACK
ACK
0
0
1
REGISTER
0 -> 1
DATA
STOP
XXh