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| Home > Program Trace Macrocell Programmer’s Model > The PTM sequencer | |||
The PTM includes a three-state sequencer. To create a multiple-stage trigger scheme, you will normally use a trigger event based on a sequencer state transition. However, when you want a trigger to be derived from a single event, you do not require the sequencer.
Figure 3.5 shows the sequencer state diagram. The sequencer can change state on every clock cycle, and a different event causes each of the possible sequencer transitions. For more information about PTM events see Event resources and PTM events.
On every cycle the sequencer does one of the following:
remains in the current state
moves to one of the other two states.
A PTM reset puts the sequencer into State 1, see Resets.
Whatever the current state of the sequencer, there are two state transition events that change its state, and:
if both of these state transition events are active the sequencer remains in its current state
if neither of these state transition events is active the sequencer remains in its current state
the behavior of the sequencer is unpredictable if either of these state transition events has not been programmed.
You can read and write the current state of the sequencer, see About the sequencer registers and Programming bit and associated state.
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