NXP Semiconductors K32 L2A Series, Reference Manual, Page: 760 / 1379

NOTE
• The trigger output is asserted one Protocol Timer Clock
cycle later than pre-trigger output. The trigger output and
the pre-trigger output de-assert at the same time.
• The pre-trigger output is asserted for two clock cycles and
trigger output is asserted for one clock cycle (except in 16-
bit Periodic Counter mode where both pre-trigger and
trigger are asserted for many cycles depending on
TMR_VAL[31:16]).
28.4.3 Trigger Control for Timers
The TSOT, TROT, TSOI and TRG_SEL, TRG_SRC bits control how the trigger input
affects the timer operation. The TRG_SEL selects the input trigger for the channel from
all other channel's trigger outputs. The TRG_SRC further selects between the selected
internal trigger and the external trigger input to the channel.
The selected trigger affects the timer operation based on TROT, TSOI & TSOT bits. The
behavior due to these bits is as follows:
• If TSOI = 1, counter stops on TIF assertion. Requires trigger (if TSOT = 1) or T_EN
rising edge (if TSOT = 0), to reload and decrement. If TSOI = 0, counter does not
stop after timeout.
• If TROT = 1, counter is loaded on each trigger; else, counter is loaded on every
T_EN rising edge or timeout rising edge (timeout not used in Capture modes).
• If TSOT = 1, counter will start to decrement on trigger. Subsequent triggers are
ignored till a counter timeout. If TSOT = 0, counter decrements immediately from
the next clock edge. TSOT has no effect when channel is Chained or in Capture
mode.
These bits affect the timer operation differently in different timer modes:
• In 32-bit Periodic Counter and Dual 16-bit Periodic Counter modes, all bits (TSOT,
TSOI & TROT) affect the timer operation as described above.
• In 32-bit Trigger Accumulator mode, only TSOI bit controls the timer function.
TROT & TSOT bits have no effect on timer operation.
• In 32-bit Input Trigger Capture mode, TSOI and TROT bits control the timer
function. TSOT bit has no effect on timer operation.
Functional description
K32 L2A Reference Manual, Rev. 2, 01/2020
760 NXP Semiconductors