UDMA Chaining

Table of Contents

• Introduction
• Supported Combinations
• Steps to Run the Example
• See Also
• Sample Output

Introduction

UDMA chaining sample application performs a chain of block copy transfer using channel global trigger. Channel 0 completion triggers Channel 1 transfer: CH0 -> CH1.

The application opens and configures two BCDMA channel using SysConfig.

The first channel doesn't user a global trigger and each channel triggers the next channel's global trigger through the channel's TR event register.

A channel's source buffer is previous channel's destination buffer. This ensures that chaining trigger works in a synchronized manner when the memory compare matches.

The transfer completion is based on last channel's DMA completion event. Once the transfer it completes, it does cache operation for data coherency and compares the source and destination buffers for any data mismatch.

Supported Combinations

Attention

A53 NORTOS, A53 FREERTOS and A53 FREERTOS SMP support is experimental and is NOT supported by TI.

Parameter	Value
CPU + OS	r5fss0-0 freertos
	a53ss0-0 nortos
	a53ss0-0 freertos
	a53ss0-0 freertos-smp
Toolchain	ti-arm-clang
	arm.gnu.aarch64-none
Board	am64x-evm
Example folder	examples/drivers/udma/udma_chaining

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)
• Launch a CCS debug session and run the executable, see CCS Launch, Load and Run

See Also

UDMA

Sample Output

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

[UDMA] Chaining application started ...
All tests have passed!!