RS5C348A RICOH Co.,Ltd., RS5C348A Datasheet - Page 26

• Manufacturer Part Number: RS5C348A
• Description: 4-wire Serial Interface Real-time Clock
• Manufacturer: RICOH Co.,Ltd.

Rx5C348A/B
Rev.2.01
Bad Example (3)
(Where a time span of less than 61µs is left between the adjacent processes of reading time data)
Good Example
SI
SO
Bad Example (1)
(Where the CE pin is once driven low in the process of reading time data)
Bad Example (2)
(Where a time span of less than 31µs is left until the start of the process of writing time data)
SI
SO
SI
SO
CE
CE
CE
12345
SO
CE
SI
0Ch
Address Pointer
Transfer Format
Register = 4h
Address Pointer
Transfer Format
Register = Ch
Address Pointer
Transfer Format
Register = 0h
Address Pointer
Transfer Format
Register = Ch
Time span of less than 31µs
= Fh
= 0h
= Fh
= 0h
31µs or more
Time span of 31µs or more
0Ch
0Ch
F4h
F0h
Data transfer from the host
Reading from
Address 0h
(sec.)
Reading from
Address Fh
(control2)
Reading from
Address 0h
(sec.)
Writing to
Address Fh
(contorl2)
DATA
Data
Data
Data
Writing to
Address 0h
(sec.)
Less than 62µs
Address Pointer
Transfer Format
Register = 4h
Data
31µs or more
= 1h
Reading from
Address 0h
(sec.)
DATA
14h
Any address other than addresses 0h to 6h
permits of immediate reading or writing without
requiring a time span of 31 µs.
Data
- 26 -
Writing to
Address 1h
(min.)
Reading from
Address 1h
(min.)
Address Pointer
Transfer Format
Register = Ch
Data
Reading from
Address 1h
(min.)
Data transfer from RTCs
= 0h
DATA
Data
0Ch
Writing to
Address 2h
(hr.)
Data
Reading from
Address 2h
(hr.)
Reading from
Address 2h
(hr.)
Reading from
Address 0h
(sec.)
DATA
Data
Data