User Manual
518
Rev. 1.1
2019-03-18
TLE984xQX
Microcontroller with LIN and Power Switches for Automotive Applications
Capture/Compare Unit 6 (CCU6)
18.3.2.2 Edge-Aligned / Center-Aligned Mode
In
Edge-Aligned Mode
(CTM = 0), timer T12 is always counting upwards (CDIR = 0). When reaching the value
given by the period register (period-match T12_PM), the value of T12 is cleared with the next counting step
(saw tooth shape).
Figure 123 T12 Operation in Edge-Aligned Mode
As a result, in Edge-Aligned mode, the timer period is given by:
T12
PER
= <Period-Value> + 1; in T12 clocks (
f
T12
)
(18.1)
In
Center-Aligned Mode
(CTM = 1), timer T12 is counting upwards or downwards (triangular shape). When
reaching the value given by the period register (period-match T12_PM) while counting upwards (CDIR = 0), the
counting direction control bit CDIR is changed to downwards (CDIR = 1) with the next counting step.
When reaching the value 0001
H
(one-match T12_OM) while counting downwards, the counting direction
control bit CDIR is changed to upwards with the next counting step.
As a result, in Center.Aligned mode, the timer period is given by:
T12
PER
= (<Period-Value> + 1) x2; in T12 clocks (
f
T12
)
(18.2)
• With the next clock event of
f
T12
the count direction is set to counting up (CDIR = 0) when the counter
reaches 0001
H
while counting down.
• With the next clock event of
f
T12
the count direction is set to counting down (CDIR = 1) when the Period-
Match is detected while counting up.
• With the next clock event of
f
T12
the counter counts up while CDIR = 0 and it counts down while CDIR = 1.
CCU6_MCT05509
f
T12
Zero
CC6x
Shadow Transfer
T12 Count
Period
Value
Period
Match
Zero
Match
Value n+1
Value n+2
CDIR
Up
Up