AM62L FreeRTOS SDK  11.00.00
EPWM Duty Cycle

Introduction

This example generates a signal for a specified time and duty cycle using ePWM module. The time and duty cycle can be configured by the user.

The example does the below

  • Configures ePWM0 to generate a 1KHz signal with 25% duty cycle for 60 seconds.
  • Output channel A is used in the example.
  • The parameters frequency, duty cycle and application run time are configurable by the user.
  • Deadband submodule and chopper submodule are entirely bypassed in this example.
  • ISR is used to keep track of keep track of elapsed time.
  • Show usage of ePWM APIs

AM62LX-EVM

  • This example uses the user expansion connector (J2) in the board for testing on AM62LX-SK.
  • All pin numbers are on the expansion connector in the board.
  • The pins configured for the example is enabled on user expansion connector based on the FET selection switch(FET_SEL0).
  • The SOC_VOUT0_DATAn are the input to FET switches. The pins that are configured for the example are pinmuxed with the FET switches.
  • The S0 select pin decides if the configured pins (which is pinmuxed with SOC_VOUT0_DATAn) map to HDMI or USER EXP connector.
  • The S0 pin is triggered to a high value in the software. When the S0 is high, the pin that is configured for the example (which is pinmuxed with SOC_VOUT0_DATAn) will be available on the user expansion connector.

The below diagram depicts the selection:

S2 S1 S0 IP(nA)/OP(nB1 (Or) nB2)
H H L nA=nB1 -> SOC - HDMI
H H H nA=nB2 -> SOC - GPIO EXP CONN

Below is the connection details.

  • Signal can be probed on Pin 18 of User Expansion Connector (J2) on the board.
  • EPWM Signal: G22/V0UT0_DATA13 (Pin_18)

Supported Combinations

Parameter Value
CPU + OS a53ss0-0 nortos
a53ss0-0 freertos
Toolchain arm.gnu.aarch64-none
Board am62lx-evm
Example folder examples/drivers/epwm/epwm_duty_cycle/

Steps to Run the Example

  • When using CCS projects to build, import the CCS project for the required combination and build it using the CCS project menu (see Using SDK with CCS Projects).
  • When using makefiles to build, note the required combination and build using make command (see Using SDK with Makefiles)
  • To Load and Run an example (see Application Run and debugging using CCS)
  • To probe the ePWM output please refer setup details as mentioned above in Introduction section

See Also

EPWM

Sample Output

Shown below is a sample output when the application is run,

EPWM Duty Cycle Test Started ...
App will wait for 60 seconds (using PWM period ISR) ...
EPWM Duty Cycle Test Passed!!
All tests have passed!!