Loop Counter Values in Programs and Watchdog Timer Overflow Interval Settings: The
values of a to h in the programs depend on the clock frequency. Table 18-14 indicates the values
for 10 MHz. Values for other frequencies can be calculated as shown below, but use the settings
in table 18-15 for the value off.
Table 18-14 Loop Counter Values in Program (10 MHz)
Variable
Clock Frequency
a
(f)
b
(f)
c
(f)
d
(f)
e
(f)
g
(f)
h
(f)
f = 10 MHz
Hexadecimal
H'0019
H'0007
H'0007
H'03B3 H'0007
H'0009 H'0004
Decimal
25
7
7
947
7
9
4
Comments
Program tVS1
tVS2
Erase
tVS1
z
tVS2
at write
at pre-write
at erase
Formula:
a
(f)
to h
(f)
=
×
{a
(f = 10)
to h
(f = 10)
}
Examples for 16 MHz:
a
(f)
=
×
25 =
40
≈
H'0028
b
(f)
=
×
7 =
11.2
≈
H'000C
c
(f)
=
×
7 =
11.2
≈
H'000C
d
(f)
=
×
947 = 1515.2
≈
H'05EC
e
(f)
=
×
7 =
11.2
≈
H'000C
g
(f)
=
×
9 =
14.4
≈
H'000F
h
(f)
=
×
4 =
6.4
≈
H'0007
Table 18-15 Watchdog Timer Overflow Interval Settings
Variable
Clock Frequency
f
10 MHz
≤
frequency
≤
16 MHz
H'A57F
2 MHz
≤
frequency < 10 MHz
H'A57E
1 MHz
≤
frequency < 2 MHz
H'A57D
Note:
The watchdog timer (WDT) set value is calculated based on the number of instructions
including write time and erase time from start to stop of WDT operation. In this program
example, therefore, no more instructions should be added between the start and stop of
WDT operation.
Clock frequency f [MHz]
10
16
10
16
10
16
10
16
10
16
10
16
10
16
10
606
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