R2023K datasheet(48/50 Pages) RICOH

48 / 50 page

R2023K/T

• Reading Time and Calendar Data

(1) Ordinary Process of Reading Time and Calendar Data

Read from Time Counter

and Calendar Counter

*2)

Stop Condition

Start Condition

*1)

(2) Basic Process of Reading Time and Calendar Data with Periodic Interrupt Function

*2)

Other Interrupt

Processes

Set Periodic Interrupt

Cycle Selection Bits

CTFG=1?

Read from Time Counter

and Calendar Counter

Yes

Control Register 2

←(X1X1X011)

Generate Interrupt in CPU

*1)

*3)

*1) When reading to clock and calendar counters, do not insert

Stop Condition until all times from second to year have been

written to prevent error in writing time. (Detailed in "P.28 Data

Transmission under Special Condition".

*2) Take care so that process from Start Condition to Stop

Condition will be complete within 0.5sec.

(Detailed in "P.28

Data Transmission under Special Condition".

*1) This step is intended to select the level mode

as a waveform mode for the periodic interrupt

function.

*2) This step must be completed within 0.5

second.

*3) This step is intended to set the CTFG bit to 0

in the Control Register 2 to cancel an interrupt to

the CPU.

R2023K Datasheet(PDF) 48 Page - RICOH electronics devices division