TIMER/EVENT COUNTER MODES OF OPERATION
7 - 14
DSP56002 TIMER AND EVENT COUNTER
MOTOROLA
7.5.7
Timer Mode 7 (Standard Timer Mode, External Clock)
Timer Mode 7 is defined by TC2-TC0 equal 111.
With the timer enabled (TE=1), the counter is loaded with the value contained by the TCR.
The counter is decremented by the transitions of the signal coming in on the TIO input pin.
At the transition that occurs after the counter has reached 0, the TS bit in TCSR is set and,
if the TIE is set, the timer generates an interrupt. The counter is reloaded with the value
TE
TCR
Start Event
Clock
xxx
Counter
0
N-1
N
Interrupt
1
TIO
Start Event
0
yyy
Stop Event
N
Figure 7-9 Pulse Width Measurement Mode (INV=1)
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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