Camera interfaces
GUPPY Technical Manual
V4.0.1
118
PWM: minimal and maximal periods and frequencies
In the following formulas you find the minimal/maximal periods and frequen-
cies for the pulse-width modulation (PWM).
PWM: Examples in practice
In this chapter we give you two examples, how to write values in the PWM
registers. All values have to be written in microseconds (µs) in the PWM reg-
isters, therefore remember always the factor 10
-6
s.
Example 1:
Set PWM with 1kHz at 30% pulse width.
Note
L
Note the following conditions:
•
PulseWidth
<
Period
•
Period
≥
MinPeriod
Formula 1: Minimal/maximal period and frequency
Formula 2: PWM example 1
period
min
3µs
=
frequency
max
1
period
min
-----------------------
1
3µs
--------
333.33kHz
=
=
=
⇒
frequency
min
1
2
16
6
–
×
10
s
-------------------------
15.26Hz
=
=
period
max
1
frequency
min
-------------------------------
2
16
µs
=
=
⇒
RegPeriod
1
frequency
6
–
×
10
s
-----------------------------------------
1
1kHz
6
–
×
10
s
-----------------------------
1000
=
=
=
RegPulseWidth
RegPeriod
30%
×
1000
30%
×
300
=
=
=