RX
−
8564
LC
Page
−
30
ETM12E-01
3) Example of processing to recover from backup mode
∗
1) Check the VL bit
(Voltage Low Flag).
∗
2)
When the VL bit = "1", it may be due to
an error during backup (clock data or
register settings may have been lost,
due to a voltage drop, etc.), so be sure
to initialize.
∗
3)
Be sure to initialize all registers. (For
further description of initialization, see
"Initialization" below.)
To next process
Backup recovery
processing
No
(
VL = " 1 " )
VL
=
"
0
"
?
Yes
(
VL
=
"
0
"
)
∗
1
∗
2
Initialization
∗
3
4) Example of clock and calendar write processing
To next process
Set current time
STOP
←
"
1
"
•
Write "1" to the STOP bit to prevent clock updates while setting the current
time.
Write current time
•
Write the data (among the [Year/Month/Day [day of
week]:hour:minute:second] data) that needs to be set (or reset).
∗
When initializing be sure to initialize all of the data.
STOP
←
"
0
"
•
Zero-clear the STOP bit to start (restart) the clock's operation.
∗
The clock starts from the set [second] + 500 ms (500 ms after the set
second). (The first [second] update occurs 500
ms later.)
5) Example of clock and calendar read processing
To next process
Read current time
Read current time
•
The required information (among the [Year/Month/Day [day of
week]:hour:minute:second] data) is read within one second.
∗
There is no need to manipulate the STOP bit.
