Intel 8XC196MH, 8XC196MD, 8XC196MC manual EPA Simplified Input-capture Structure

EVENT PROCESSOR ARRAY (EPA)

EPA

Interrupt

Pending Bit

Set

TIMERx

Event Occurs

at EPA Pin

Capture Buffer

EPAx_TIME

Read-out Time Value

A2458-02

Figure 11-6. EPA Simplified Input-capture Structure

If a third event occurs before the CPU reads the event-time register, the overwrite bit (EPAx_CON.0) determines how the EPA will handle the event. If the bit is clear, the EPA ignores the third event. If the bit is set, the third event time overwrites the second event time in the capture buffer. Table 11-5 summarizes the possible actions when a valid event occurs.

NOTE

In order for an event to be captured, the signal must be stable for at least two state times both before and after the transition occurs (Figure 11-7).

Event 1
	2 State	2 State
	Times	Times
Event 2
	2 State	2 State
	Times	Times

A3130-01

Figure 11-7. Valid EPA Input Events

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