rs5c338a RICOH Co.,Ltd., rs5c338a Datasheet - Page 21

• Manufacturer Part Number: rs5c338a
• Description: 3-wire Serial Interface Real-time Clock Ics With Voltage Monitoring Function
• Manufacturer: RICOH Co.,Ltd.

USAGES
1. Data Transfer Formats
1.1 Timing Between CE Pin Transition and Data Input/Output
The R
(Serial Input/Output), pins to receive and send data to and from the CPU. The 3-wire serial interface provides two
types of input/output timings with which the output and input from the SIO pin output and input are synchronized
with the rising and falling edges of the SCLK pin input, respectively, and vice versa. The R
to select either one of two different input/output timings depending on the level of the SCLK pin in the low to high
transition of the CE pin. Namely, when the SCLK pin is held low in the low to high transition of the CE pin, the
models will select the timing with which the output and input from the SIO pin are synchronized with the rising and
falling edges of the SCLK pin input, respectively, as illustrated in the timing chart below.
Conversely, when the SCLK pin is held high in the low to high transition of the CE pin, the models will select the
timing with which the output and input from the SIO pin are synchronized with the falling and rising edges of the
SCLK pin input, respectively as illustrated in the timing chart below.
(Output from the real-time clock)
(Output from the real-time clock)
(Input to the real-time clock)
(Input to the real-time clock)
×
5C338A adopt a 3-wire serial interface by which it uses the CE (Chip Enable), SCLK (Serial Clock), and SIO
CE
SCLK
CE
SCLK
SIO
SIO
SIO
SIO
t
t
CES
CES
t
t
DS
DS
t
t
DH
DH
t
t
RD
RD
×
5C338A are configured
R
×
5C338A
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