Datasheet

V850ES/JG3 CHAPTER 10 WATCH TIMER FUNCTIONS
R01UH0015EJ0300 Rev.3.00 Page 392 of 870
Sep 30, 2010
10.4.2 Operation as interval timer
The watch timer can also be used as an interval timer that repeatedly generates an interrupt request signal (INTWTI) at
intervals specified by a preset count value.
The interval time can be selected by the WTM4 to WTM7 bits of the WTM register.
Table 10-1. Interval Time of Interval Timer
WTM7 WTM6 WTM5 WTM4 Interval Time
0 0 0 0 2
4
× 1/fw 488 μ s (operating at fW = fXT = 32.768 kHz)
0 0 0 1 2
5
× 1/fw 977 μ s (operating at fW = fXT = 32.768 kHz)
0 0 1 0 2
6
× 1/fw 1.95 ms (operating at fW = fXT = 32.768 kHz)
0 0 1 1 2
7
× 1/fw 3.91 ms (operating at fW = fXT = 32.768 kHz)
0 1 0 0 2
8
× 1/fw 7.81 ms (operating at fW = fXT = 32.768 kHz)
0 1 0 1 2
9
× 1/fw 15.6 ms (operating at fW = fXT = 32.768 kHz)
0 1 1 0 2
10
× 1/fw 31.3 ms (operating at fW = fXT = 32.768 kHz)
0 1 1 1 2
11
× 1/fw 62.5 ms (operating at fW = fXT = 32.768 kHz)
1 0 0 0 2
4
× 1/fw 488 μ s (operating at fW = fBRG = 32.768 kHz)
1 0 0 1 2
5
× 1/fw 977 μ s (operating at fW = fBRG = 32.768 kHz)
1 0 1 0 2
6
× 1/fw 1.95 ms (operating at fW = fBRG = 32.768 kHz)
1 0 1 1 2
7
× 1/fw 3.91 ms (operating at fW = fBRG = 32.768 kHz)
1 1 0 0 2
8
× 1/fw 7.81 ms (operating at fW = fBRG = 32.768 kHz)
1 1 0 1 2
9
× 1/fw 15.6 ms (operating at fW = fBRG = 32.768 kHz)
1 1 1 0 2
10
× 1/fw 31.3 ms (operating at fW = fBRG = 32.768 kHz)
1 1 1 1 2
11
× 1/fw 62.5 ms (operating at fW = fBRG = 32.768 kHz)
Remark fW: Watch timer clock frequency