Operation As Interval Timer - NEC V850ES/F 3-L Series User Manual

Watch Timer Functions

13.4.2 Operation as interval timer

Table 13-3
WTM7 WTM6
0 0
0 0
0
0
0 0
0 1
0 1
0 1
0 1
1 0
1 0
1 0
1 0
1 1
1 1
1 1
1 1
Note
The Watch Timer can also be used as an interval timer that repeatedly
generates an interrupt at intervals specified by a preset count value.
The interval time can be selected by the WTM4 to WTM7 bits of the WTM
register.
Interval time of itimer
WTM5 WTM4
4
0 0 2
5
0 1 2
6
2
1 0
7
1 1 2
8
0 0 2
9
0 1 2
10
1 0 2
11
1 1 2
4
0 0 2
5
0 1 2
6
1 0 2
7
1 1 2
8
0 0 2
9
0 1 2
10
1 0 2
11
1 1 2
f : Watch Timer clock frequency
W
f : Sub oscillator frequency
XT
f : Prescaler3 output frequency
BRG
User's Manual U18743EE1V2UM00
Interval Time
× 1/f
488 µs (operating at f
w
× 1/f
977 µs (operating at f
w
× 1/f
1.95 ms (operating at f
w
× 1/f
3.91 ms (operating at f
w
× 1/f
7.81 ms (operating at f
w
× 1/f
15.6 ms (operating at f
w
× 1/f
31.3 ms (operating at f
w
× 1/f
62.5 ms (operating at f
w
× 1/f
488 µs (operating at f
w
× 1/f
977 µs (operating at f
w
× 1/f
1.95 ms (operating at f
w
× 1/f
3.91 ms (operating at f
w
× 1/f
7.81 ms (operating at f
w
× 1/f
15.6 ms (operating at f
w
× 1/f
31.3 ms (operating at f
w
× 1/f
62.5 ms (operating at f
w
Chapter 13
= f = 32.768 KHz)
W XT
= f = 32.768 KHz)
W XT
= f = 32.768 KHz)
W XT
= f = 32.768 KHz)
W XT
= f = 32.768 KHz)
W XT
= f = 32.768 KHz)
W XT
= f = 32.768 KHz)
W XT
= f = 32.768 KHz)
W XT
= f = 32.768 KHz)
W BRG
= f = 32.768 KHz)
W BRG
= f = 32.768 KHz)
W BRG
= f = 32.768 KHz)
W BRG
= f = 32.768 KHz)
W BRG
= f = 32.768 KHz)
W BRG
= f = 32.768 KHz)
W BRG
= f = 32.768 KHz)
W BRG
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