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Fifo programmed cyclic waveform generation, Fifo pulsed waveform generation, Figure 3-14. fifo programmed cyclic waveform timin – National Instruments AT-MIO-16X User Manual

Page 89: Figure 3-15. fifo pulsed waveform generation timin

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Chapter 3

Theory of Operation

© National Instruments Corporation

3-23

AT-MIO-16X User Manual

FIFO Programmed Cyclic Waveform Generation

One step beyond the continuous waveform generation is the
programmed cyclic waveform generation. This mode is also available
only when the entire buffer fits within the DAC FIFO. Figure 3-14
shows the operation of this mode.

Figure 3-14. FIFO Programmed Cyclic Waveform Timing

In this case, one of the counters in the Am9513A Counter/Timer is
programmed to count the number of DAC FIFO Retransmit signals.
When the counter counts the appropriate number of occurrences, it
terminates the waveform sequence. A bit is available in Status Register
1 to indicate termination of a waveform sequence.

FIFO Pulsed Waveform Generation

Another step beyond cycle counting is pulsed waveform generation.
Again, this mode is applicable only if the entire buffer fits within the
DAC FIFO. Figure 3-15 shows the operation of this mode and the
resulting waveform.

Figure 3-15. FIFO Pulsed Waveform Generation Timing

COUNTER 1, 2, or 5

5

4

3

2

1

0

5

DACFIFORT*

2

1

2

1

2

1

2

CTR 1

DACFIFORT*

CTR 2 Terminal Count

CTR 1 Output