tsl2561cs Pacer Components, tsl2561cs Datasheet - Page 10

• Manufacturer Part Number: tsl2561cs
• Description: Light-to-digital Converter
• Manufacturer: Pacer Components

TSL2560, TSL2561
LIGHT-TO-DIGITAL CONVERTER
TAOS059L − JANUARY 2008
10
Copyright E 2008, TAOS Inc.
When an SMBus Block Write or Block Read is initiated (see description of COMMAND Register), the byte
following the COMMAND byte is ignored but is a requirement of the SMBus specification. This field contains
the byte count (i.e. the number of bytes to be transferred). The TSL2560 (SMBus) device ignores this field and
extracts this information by counting the actual number of bytes transferred before the Stop condition is
detected.
When an I
SMBus protocol specification. Data bytes continue to be transferred from the TSL2561 (I
until a NACK is sent by the Master.
The data formats supported by the TSL2560 and TSL2561 devices are:
D
D
D
For a complete description of SMBus protocols, please review the SMBus Specification at
http://www.smbus.org/specs. For a complete description of I
at http://www.semiconductors.philips.com.
Master transmitter transmits to slave receiver (SMBus and I
−
Master reads slave immediately after the first byte (SMBus only):
−
Combined format (SMBus and I
−
The transfer direction in this case is not changed.
At the moment of the first acknowledgment (provided by the slave receiver) the master transmitter
becomes a master receiver and the slave receiver becomes a slave transmitter.
During a change of direction within a transfer, the master repeats both a START condition and the slave
address but with the R/W bit reversed. In this case, the master receiver terminates the transfer by
generating a NACK on the last byte of the transfer and a STOP condition.
2
C Write or I
A
P
Rd
S
Sr
Wr
X
...
Figure 7. SMBus and I
2
C Read (Combined Format) is initiated, the byte count is also ignored but follows the
Acknowledge (this bit position may be 0 for an ACK or 1 for a NACK)
Stop Condition
Read (bit value of 1)
Start Condition
Repeated Start Condition
Write (bit value of 0)
Shown under a field indicates that that field is required to have a value of X
Continuation of protocol
Master-to-Slave
Slave-to-Master
1
S
Slave Address
r
7
2
C):
www.taosinc.com
Wr
2
1
C Packet Protocol Element Key
A
X
1
Data Byte
2
C protocols, please review the I
8
2
C):
r
1
A
X
1
P
The LUMENOLOGY r Company
2
C) device to Master
2
C Specification