User Manual
455
Rev. 1.1
2019-03-18
TLE984xQX
Microcontroller with LIN and Power Switches for Automotive Applications
General Purpose Timer Units (GPT12)
External Count Clock Input
The external input signals of the GPT1 block are sampled with the GPT1 basic clock (see
). To ensure
that a signal is recognized correctly, its current level (high or low) must be held active for at least one complete
sampling period, before changing. A signal transition is recognized if two subsequent samples of the input
signal represent different levels. Therefore, a minimum of two basic clock periods are required for the
sampling of an external input signal. Thus, the maximum frequency of an input signal must not be higher than
half the basic clock.
summarizes the resulting requirements for external GPT1 input signals.
These limitations are valid for all external input signals to GPT1, including the external count signals in
Counter Mode and Incremental Interface Mode, the gate input signals in Gated Timer Mode, and the external
direction signals.
16.3.6
Interrupt Control for GPT1 Timers
When a timer overflows from FFFF
H
to 0000
H
(when counting up), or when it underflows from 0000
H
to FFFF
H
(when counting down), its interrupt request flag in register GPT12E_T2, GPT12E_T3, or GPT12E_T4 will be set.
This will cause an interrupt to the respective timer interrupt vector, if the respective interrupt enable bit is set.
In
Reload Mode
, upon a trigger signal, T3 is loaded with the contents of the respective timer (T2 or T4) and the
respective interrupt request flag in register GPT12E_T2 or GPT12E_T4 is set.
In
Incremental Interface Mode
, the interrupt request generation can be selected as follows:
• In Rotation Detection Mode (T3M = 110
B
), an interrupt request is generated each time the count direction
of T3 changes.
• In Edge Detection Mode (T3M = 111
B
), an interrupt request is generated each time a count edge for T3 is
detected.
In
Capture Mode
, upon a trigger (selected transition) at the corresponding input pin the content of the core
timer T3 are loaded into the auxiliary timer register Tx and the associated interrupt request flag in register
GPTE12_T2 or GPT12E_T4 will be set.
19.53 kHz
51.2 µs
3.355 s
512
78.125 kHz
12.8 µs
838.9 ms
9.77 kHz
102.4 µs
6.711 s
1024
39.06 kHz
25.6 µs
1.678 s
4.88 kHz
204.8 µs
13.42 s
2048
19.53 kHz
51.2 µs
3.355 s
2.44 kHz
409.6 µs
26.84 s
4096
9.77 kHz
102.4 µs
6.711 s
Table 241 GPT1 External Input Signal Limits
GPT1 Basic Clock = 10 MHz
Input
Frequ.
Factor
GPT1
Divider
BPS1
Input Phase
Duration
GPT1 Basic Clock = 40 MHz
Max. Input
Frequency
Min. Level Hold
Time
Max. Input
Frequency
Min. Level Hold
Time
1.25 MHz
400 ns
f
GPT
/8
01
B
4 ×
t
GPT
5.0 MHz
100 ns
625.0 kHz
800 ns
f
GPT
/16
00
B
8 ×
t
GPT
2.5 MHz
200 ns
312.5 kHz
1.6 µs
f
GPT
/32
11
B
16 ×
t
GPT
1.25 MHz
400 ns
156.25 kHz
3.2 µs
f
GPT
/64
10
B
32 ×
t
GPT
625.0 kHz
800 ns
Table 240 GPT1
Timer
Parameters
(cont’d)
Module Clock
f
GPT
= 10 MHz
Overall
Prescaler
Factor
Module Clock
f
GPT
= 40 MHz
Frequency
Resolution
Period
Frequency
Resolution
Period