Lab to practice with the SDK on the ETS-EVO

Introduction

In this LAB we will learn how to:

• build an executable to be run on the ETS-EVO,
• control the LED on the ETS-EVO front panel.

What is required:

• basic knowledge of the C programming language,
• Software SDK and associated tools,
• ETS-EVO register mapping¹.

Create a new project

Go to the Petalinux installation directory and navigate to software/user-apps folder. Create a new project: petalinux-new-app lab1. This creates an empty project with two important files:

• lab1.c,
• Makefile.

In order to control the LEDs we have to know the locations they are mapped to. This is clearly depicted on the ETS-EVO register mapping document.

COUNTER_CTRL 0x81400038
Read-write
[...]
[31..28] output leds

Since the hardware uses a MMU is not possible to directly write to this location, but a mapping has to be done first. A wrapper utility (mmu.c) has been included to handle the internals of this mapping. So the user is able to issue:

*(volatile unsigned long *) MMU_ADDR(0x81400038) = 0xF0000000;

to turn on all the LEDs. The mmu.o object has to be added to the Makefile and some additional calls have to be issued to the wrapper utility (do_mmap and do_munmap) in the lab1.c file. For simplicity please overwrite the project folder with the one attached to this document and issue a make command to compile the executable.

Run the executable on the board

Copy the executable to the target board with the command: putftp lab1 192.168.200.2 (change IP address accordingly). Log in on the board via Telnet (credentials are user: root - password: root). The board will be probably running its default firmware so it is better to temporarily stop it during the lab execution, by running the following commands:

killall microref_loop
killall microref

It is possible to check if the microref executable has been succesfully stopped by issuing a ps command. Now in order to run the freshly built program is necessary to make it executable by issuing:

cd /var/ftp
chmod 755 lab1

And launch it with:

./lab1

You should get an output like this:

/var/ftp # ./lab1
/dev/mem opened.
Memory 0x80000000 (size 0x10000000) mapped at address 0x4818b000
HW version: 22
Toggling LEDs.. (press CTRL-C to quit)

To stop simply press CTRL-C.

Congratulations! You were successful in running your first custom program on the ETS-EVO board.

Downloads

• Lab to practice with the SDK on the ETS-EVO
• Source code

 

__________________________________________________________________________________
¹ Can be downloaded from ETS-EVO product sheet, documentation tab.