Fujitsu F2MC-16LX Hardware Manual page 315

D : divide ratio selected via the divide ratio register DIVR
IV
(use 1, except in divide frequency measurement mode)
I Range for counting the pulse width/interval
Depending on the selected combination of count clock and divide ratio of the input divider, the
allowed pulse width/interval range for measurement will vary.
Table 14.3-7 "List of pulse width measurement ranges" shows a list of measurement ranges
when a machine clock (Φ, hereafter) of 16 MHz is applied.
Table 14.3-7 List of pulse width measurement ranges
Divide ratio DIV1
No division
-
Divide-by-4
0
Divide-by-16
0
Divide-by-64
1
Divide-by-256
1
Note: The value in [] indicates the resolution per bit.
I Generation of interrupt requests
In pulse width measurement mode, two types of interrupt requests can be generated, as listed
below:
❍ Interrupt requests due to timer overflows
If an overflow occurs due to incrementing in measurement mode, an overflow flag is set. If
overflow interrupt requests are enabled, an interrupt request is generated.
❍ Interrupt requests due to the end of measurement
If measurement end interrupt requests are enabled, an interrupt request is generated when a
measurement end edge is detected and the PWCSR's measurement end flag (EDIR) is set.
The measurement end flag EDIR is automatically cleared when the measurement result is read
out from the PWCR.
I Operational flow of pulse width measurement
Figure 14.3-6 "Operational flow of pulse width measurement" shows the operational flow of
pulse width measurement.
CKS1,0=00 (Φ Φ Φ Φ /4)
DIV0
0.25 µs to 16.38 ms
-
[0.25 µs]
0.25 µs to 4.1 ms
0
[6.25 µs]
0.25 µs to 1.024 ms
1
[15.6 ns]
0.25 µs to 256 µs
0
[3.91 µs]
0.25 µs to 64 µs
1
[0.98 µs]
CHAPTER 14 PWC TIMER
CKS1,0=00 (Φ Φ Φ Φ /16)
0.25 µs to 65.5 ms
[1.6 µs]
0.25 µs to 16.38 ms
[0.4 µs]
0.25 µs to 4.1 ms
[1.6 µs]
0.25 µs to 1.024 ms
[25 µs]
0.25 µs to 256 µs
[6.25 µs]
CKS1,0=00 (Φ Φ Φ Φ /32)
0.25 µs to 131 ms
[3.2 µs]
0.25 µs to 52.4 ms
[0.8 µs]
0.25 µs to 13.1 ms
[0.2 µs]
0.25 µs to 3.27 ms
[50 ns]
0.25 µs to 817 µs
[12.5 ns]
299