RS5C372A-E2-F Datasheet, PDF (33/57 Pages) RICOH electronics devices division – I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC

RS5C372A/B
1.2-5 Data transmission read format of the RS5C372A/B
The RS5C372A/B allow the following three readout methods of data from an internal register.
1) The first method to reading data from the internal register is to specify an internal address by setting the
internal address pointer and the transmission format register described 1.2-4, generate the repeated start
condition (see section 1.2-3) to change the data transmission direction to perform reading. The internal
address pointer is set to Fh when the stop condition is met. Therefore, this method of reading allows no
insertion of the stop condition before the repeated start condition. Set 0h to the transmission format register.
Example 1 of data read (when data is read from 2h to 4h)
R/W=0 (Write)
Repeated start condition
R/W=1 (Read)
S 0 1 1 0 0 1 0 0 A 0 0 1 0 0 0 0 0 A Sr 0 1 1 0 0 1 0 1 A
Transmission of
slave address
(0110010)
Setting of
2h to the
internal
address
pointer
Setting of
0h to the
trans-
mission
format
register
Transmission of
slave address
(0110010)
Data
A
Data
A
Data
AP
Reading of data from
the internal address 2h.
Reading of data from
the internal address 3h.
Reading of data from
the internal address 4h.
Master to slave
S Start condition
A A A Acknowledge signal
Slave to master
Sr Repeated start condition
P Stop condition
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