RV5C339A_03 Datasheet, PDF (26/46 Pages) RICOH electronics devices division – 3-WIRE SERIAL INTERFACE REAL-TIME CLOCK IC WITH VOLTAGE MONITORING FUNCTION

RV5C339A
Good Example
CE
SIO
Time span of 31µs or more
F4h
Data
Specifying Fh in the Reading from the
address pointer
control register 2
Writing 4h to the at address Fh
transfer format register
Any address other than addresses 0h to 6h
permits of immediate reading or writing
without requiring a time span of 31µs.
Data
Reading from
the second
counter at
address 0h
Data
Data
Reading from
the minute
counter at
address 1h
Reading from
the hour counter
at address 2h
Bad Example (1) (Where the CE pin is once driven low in the process of reading time data)
Time span of
31µs or more
CE
Time span of
31µs or more
SIO
0Ch
Data
14h
Data
Data
Specifying 0h in the
address pointer
Writing Ch in the
transfer format register
Reading from
the second
counter
at address 0h
Specifying 1h in the
address pointer
Writing 4h in the
transfer format register
Reading from
the minute
counter
at address 1h
Reading from
the hour counter
at address 2h
Bad Example (2) (Where a time span of less than 31µs is left until the start of the process of writing time data)
Time span of less than 31µs
CE
SIO
F0h
Data
Data
Data
Data
Specifying Fh in the Writing to the
address pointer
control register 2
Writing 0h to the
at address Fh
transfer format register
Writing to the
second counter
at address 0h
Writing to the
minute counter
at address 1h
Writing to the
hour counter
at address 2h
Bad Example (3) (Where a time span of less than 61µs is left between the adjacent processes of reading time data)
Time span of
less than 61µs
CE
SIO
0Ch
Data
0Ch
Data
Specifying 0h in the Reading from the
address pointer
second counter
Writing Ch to the at address 0h
transfer format register
Specifying 0h in the Reading from the
address pointer
second counter
Writing Ch to the at address 0h
transfer format register
0Ch
Data transfer from the host
Data
Data transfer from the real-time clocks
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