EPWM valley switching

Table of Contents

• Introduction
• External Connections
  • AM263X-CC or AM263PX-CC
  • AM263X-LP or AM263PX-LP
• Supported Combinations
• Steps to Run the Example
• See Also
• Sample Output

Introduction

EPWM Valley Switching

This example configures ePWMx as follows

• ePWMx with DCAEVT1 forcing the ePWM output LOW
• GPIO_A is used as the input to the INPUT XBAR INPUT1
• INPUT1 (from INPUT XBAR) is used as the source for DCAEVT1
• GPIO_B is set to output and toggled in the main loop to trip the PWM
• ePWMx with DCBEVT1 forcing the ePWM output LOW
• GPIO_A is used as the input to the INPUT XBAR INPUT1
• INPUT1 (from INPUT XBAR) is used as the source for DCBEVT1
• GPIO_B is set to output and toggled in the main loop to trip the PWM
• DCBEVT1 uses the filtered version of DCBEVT1
• The DCFILT signal uses the valley switching module to delay the
• DCFILT signal by a software defined DELAY value.

Block Diagram for EPWM Valley Switching example

External Connections

• For AM263x-CC or AM263Px-CC
  • GPIO48 is connected to GPIO122.
  • EPWM0_A and EPWM0_B pin can be connected to an oscilloscope to view the waveform.
• For AM263x-LP or AM263Px-LP
  • GPIO11 is connected to GPIO12.
  • EPWM1_A and EPWM1_B pin can be connected to an oscilloscope to view the waveform.

AM263X-CC or AM263PX-CC

When using AM263x-CC or or AM263Px-CC with TMDSHSECDOCK (HSEC180 controlCARD Baseboard Docking Station)

• Connect HSEC Pin 52 to HSEC Pin 72
• Capture waveform on HSEC Pin 49 for epwm0_A
• Capture waveform on HSEC Pin 51 for epwm0_B

AM263X-LP or AM263PX-LP

• Connect boosterpack header J1/J3 pin 7 to J2/J4 pin 18
• Capture waveform on boosterpack header J2/J4 Pin 37 for epwm1_A
• Capture waveform on boosterpack header J2/J4 Pin 38 for epwm1_B

Supported Combinations

Parameter	Value
CPU + OS	r5fss0-0 nortos
Toolchain	ti-arm-clang
Board	am263x-cc, am263x-lp
Example folder	examples/drivers/epwm/epwm_valley_switching

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)
• Establish connections as mentioned in External Connections section
• Launch a CCS debug session and run the executable, see CCS Launch, Load and Run

See Also

EPWM

Sample Output

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

EPWM Valley Switching Test Started ...
EPWM Valley Switching Test Passed!!
All tests have passed!!

EPWM Valley Switching waveform