333
When a compare match B occurs before the compare match A, the 0 data transfer can be
performed before the 1 data transfer, so a non-overlapping waveform can be output. In such cases,
be sure not to change the NDR contents until the compare match A after the compare match B
occurs (non-overlap period). This can be ensured by writing the next data to NDR in the IMIA
interrupt handling routine. The DMAC can also be started using an IMIA interrupt. However,
these write operations should be performed prior to the next compare match B. The timing is
shown in figure 11.10.
Compare
match A
Compare
match B
NDR
DR
NDR write
NDR write
0/1 output
0 output
NDR write
disable period
NDR write period
0/1 output
0 output
NDR write
disable period
NDR write period
Figure 11.10 Non-Overlap Operation and NDR Write Timing
Содержание HD6417032
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