sctimer_input_capture#
Overview#
The SCTimer project is a demonstration program of the SDK SCTimer driver’s input capture feature. This example uses Event 0 to 4, State 0 and 1, Capture 0 to 3, Match 4, one user defined input.
If high level input is detected on the channel when SCTimer timer starts, SCTimer will generate a capture event incorrectly although there is no rising edge. So this example ignore first pluse and capture second pluse. Event 0 and 1 occur in state 0. They are triggered by first rising and falling edge. After event 1 is triggered, new state is state 1. Event 2 and 3 are triggered continuously by following rising and falling edge in state 1. Event 0,1,2,3 cause Capture 0,1,2,3 individually. SCTimer capture second pluse in state 1. Event 4 is used as counter limit(reset). Event 4 causes Match 4, match value is 65535.
This example gets the capture value of the input signal using API SCTIMER_GetCaptureValue() in Event 2 and 3 interrupt.
Need to ensure to input least two pluse into the channel, a pwm signal is recommended. This example will print the capture values and pluse width of the input signal on the terminal window.
Supported Boards#
FRDM-RW612
Hardware requirements
Micro USB cable
FRDM-RW612 board
Personal Computer
Board settings
Connect J1-1(SCT In 1) to 1kHz, dutycycle 50% PWM signal.
Connect a micro USB cable between the PC host and the MCU-Link USB port (J10) on the board
Open a serial terminal with the following settings:
115200 baud rate
8 data bits
No parity
One stop bit
No flow control
Download the program to the target board.
Launch the debugger in your IDE to begin running the demo.
Running the demo
The log below shows example output of the SCTimer driver simple PWM demo in the terminal window:
SCTimer edge capture example
Once the input signal is received the capture values are printed
The input signal's pulse width is calculated from the capture values & printed
Capture2: 12301 Capture3: 17265 Pluse Width: 500 us
RD-RW612-BGA
Hardware requirements
Micro USB cable
RD-RW612-BGA board
Personal Computer
Board settings
Connect HD2-5(SCT In 1) to 1kHz, dutycycle 50% PWM signal.
Connect a micro USB cable between the PC host and the MCU-Link USB port (J7) on the board
Open a serial terminal with the following settings:
115200 baud rate
8 data bits
No parity
One stop bit
No flow control
Download the program to the target board.
Launch the debugger in your IDE to begin running the demo.
Running the demo
The log below shows example output of the SCTimer driver simple PWM demo in the terminal window:
SCTimer edge capture example
Once the input signal is received the capture values are printed
The input signal's pulse width is calculated from the capture values & printed
Capture2: 12301 Capture3: 17265 Pluse Width: 496 us