User Manual
515
Rev. 1.1
2019-03-18
TLE984xQX
Microcontroller with LIN and Power Switches for Automotive Applications
Capture/Compare Unit 6 (CCU6)
18.3.1
T12 Overview
shows a detailed block diagram of Timer T12. The functions of the timer T12 block are controlled
by bits in registers TCTR0, TCTR2, and PISEL0.
Timer T12 receives its input clock (
f
T12
) from the module clock
f
CC6
via a programmable prescaler and an
optional 1/256 divider or from an input signal T12HR. These options are controlled via bit fields T12CLK and
T12PRE (see
). T12 can count up or down, depending on the selected operation mode. A direction
flag, CDIR, indicates the current counting direction.
Figure 122 Timer T12 Logic and Period Comparators
Via a comparator, the T12 counter register T12 is connected to a Period Register T12PR. This register
determines the maximum count value for T12.
In Edge-Aligned mode, T12 is cleared to 0000
H
after it has reached the period value defined by T12PR. In
Center-Aligned mode, the count direction of T12 is set from ‘up’ to ‘down’ after it has reached the period value
(please note that in this mode, T12 exceeds the period value by one before counting down). In both cases,
signal T12_PM (T12 Period Match) is generated. The Period Register receives a new period value from its
Shadow Period Register.
A read access to T12PR delivers the current period value at the comparator, whereas a write access targets the
Shadow Period Register to prepare another period value. The transfer of a new period value from the Shadow
Period Register into the Period Register (see
) is controlled via the ‘T12 Shadow Transfer’
control signal, T12_ST. The generation of this signal depends on the operating mode and on the shadow
CCU6_MCA05508
Comp.
= ?
Period Register
Period Shadow
Register
T12_PM
Counter Register
T12
f
CC6
Write to
T12PR
Read from
T12PR
T12_OM
T12_ZM
= 0000
H
= 0001
H
T12_ST
256
n
Clock
Selection
edge
detection
T12HR
T12PRE
T12CLK
ISCNT12
T12STD
T12STR
CTM
T12RR
T12RS
T12R
CDIR
T12RES
T12SSC
T12
Control
& Status
STE12
edge
detection
T12RSEL
T12CNT
f
T12