Z-World PK2300, User Manual

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PK2300 Software Reference s 85
However, although the use of “noop” edges seems to be compute-time
inexpensive, it does require the application to maintain the location of
the non-noop edges. In other words, the application must maintain a
duty cycle variable for each channel in addition to a variable for the
waveform pattern buffer.
Recall that the second problem of changing the duty cycle is the
requirement for the change to be phase synchronized to the current
waveform. Many of the involved issues are similar to those of refresh-
ing the DMA counter and pointer. The driver software library provides
the function
dmapwmSwBuf
to switch waveform pattern buffers.
The following sample programs in the Dynamic C
SAMPLES\PK23XX
subdirectory provide more detailed
examples.
DMAPWM1.C
DMAPWM2.C
DMAPWM3.C
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