S-35770E01A-K8T2U Datasheet, PDF (11/26 Pages) Seiko Instruments Inc – CONVENIENCE TIMER

Rev.1.2_00
FOR AUTOMOTIVE 125°C OPERATION 2-WIRE COUNTER CONVENIENCE TIMER
S-35770 Series
 External Clock Signal Count Function
The S-35770 Series detects the change of the CLKIN pin from "L" to "H", and then starts the count-up action of the
counter. The counter is a 24-bit binary counter which can count from 0 to 16,777,215 (FFFFFF h). After reaching
16,777,215, the S-35770 Series detects the change of the CLKIN pin from "L" to "H", the counter loops back_{__}t_{_}o_{___}0_{_}.
The counter value can be confirmed by reading the count register. To initialize the counter, input "L" to the RST pin or
input the reset command to the free register. Regarding the count register and the reset command, refer to
" Configuration of registers".
RST
CLKIN
Counter
0
123 0
123 0 123
16,777,214 16,777,215
0
1
The counter does
not start the
count-up action at
RST pin = "L".
The counter is reset
at RST pin = "L".
The counter starts the count-up action
at the rising edge of CLKIN pin.
The counter is reset by
the reset command.
Figure 13 Counter Operation
The counter loops back to 0.
During communication, the S-35770 Series does not detect the change of the CLKIN pin from "L" to "H" and maintains
the counter data. The duration of the communication is defined as the time period from the start condition to the stop
condition. The count-up action of the counter is executed 1 time if the CLKIN pin is "L" when the start condition is
recognized and if the CLKIN pin is "H" when the stop condition is recognized.
RST
SDA
STA
STO
STA
STO
STA
STO
STA
STO
STA
STO
CLKIN
Counter ^{0 1 2}
34
5
6
The counter does not
start the count-up action
during communication.
The counter does not start the count-up action during
communication.
The counter starts the count-up action 1 time when
communication ends.
The counter does not
start the count-up action
during communication.
Figure 14 Counter Operation during Communication
The counter does not start
the count-up action.
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