S35710 Datasheet, PDF (15/33 Pages) Seiko Instruments Inc – FOR AUTOMOTIVE 125C OPERATION 2-WIRE

Rev.1.3_00
FOR AUTOMOTIVE 125°C OPERATION 2-WIRE CONVENIENCE TIMER
S-35710 Series
2. 2 Read mode
After the timer starts to operate, if write operation is not performed to the wake-up time register, the interrupt signal is
not output from the INT pin. The timer stops at "FFFFFF h". The timer value during timing can be confirmed by
reading the time register. This operation is called_{___}"_{_}r_{_}e_{__}ad mode".
In order for the timer to operate again, set the RST pin from "L" to "H" or perform write operation to the wake-up
time register. Regarding the operation, refer to Figure 14 and Figure 15.
Figure 20 and Figure 21 show the status transition diagram about the handshake time-out operation.
Timer reset
Timer = "0 h"
INT pin = "H"
Automatic
migration
Count up every
second
Write
Write
Timing status
INT pin = "H"
RST pin = "L"
Write
Read
Timer
= Wake-up time register
Timing stop status
INT pin = "L"
Read
RST pin = "L"
Write
Timer reset
Wake-up time register = "0 h"
Timer = "0 h"
INT pin = "L"
Read
Write mode
RST pin = "H"
Write
Power-on
RST pin = "L"
Initial status
Wake-up time register = "0 h"
Timer = "0 h"
INT pin = "H"
RST pin = "H"
RST pin = "L"
Count up every
second
Timing status
INT pin = "H"
Read
Timer = "FFFFFF h"
Write
RST pin = "L"
Timing stop status
INT pin = "H"
Read
Read mode
Remark Write: Wake-up time register write command
Read: Time register read command
Figure 20 Status Transition Diagram of Handshake Time-out (Nch Open-drain Output)
Seiko Instruments Inc.
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