P(n)
P(n+1)
HET[2]
ext. ref.
signal
APCNT
period
counter
SCNT
step
counter
ACNT
angle
generator
Deceleration
Acceleration
ACF
Acceleration
K-1
0
1
2
0
1
2
0 1
flag
DCF
Deceleration
flag
K-1
Angle Functions
826
SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
High-End Timer (N2HET) Module
ACNT detects period variations of the external signal measured by APCNT and compensates related
counting errors. A period increase is flagged in the deceleration flag. A period decrease is flagged in the
acceleration flag. If no variation is flagged, ACNT increments the counter value each time SCNT reaches
its target. If acceleration is detected, ACNT increments the counter value on each timer resolution (fast
mode). If deceleration is detected, ACNT is stopped.
illustrates how the compensations for
acceleration and deceleration operate.
Figure 20-32. ACNT Period Variation Compensations