Kalycito Infotech Private Limited

6/2 & 6/3, Pappampatti Pirivu

Trichy Road, Kannampalayam

Coimbatore - 641103, Tamil Nadu, INDIA

www.kalycito.com

SUBMITTED BY:

S Harshavardhana Reddy II Year B.Tech Electrical and Electronics Engineering NITK Surathkal

SUMMER

INTERNSHIP

REPORT

16 June 2015 – 15 July 2015

CONTENTS

S.NO. TOPIC PAGE NO.

1 POWERLINK 3

2 RASPBERRY PI 2 4

3 openPOWERLINK 8

4 openPOWERLINK with RaspberryPi2 9

5 Application developed for RaspberryPi2 kit

10

6 RaspberryPi2 Kit Setup Drawing 11

7 Remotely connecting RPi2 Boards

12

8 Observations while making application 13

9

openPOWERLINK with XILINX ZYNQ

14

POWERLINK

Open Real Time Ethernet protocol.

Fast Reaction Time- Mix of timeslot and Polling procedures.

Nodes: MN (Master-Managing Node) and CN (Slave- Controlled Node).

Better than TCP/IP in Real Time applications.

Function of MN:

Defines the clock pulse for synchronization of all devices.

Manages the data communication cycle.

Frames in POWERLINK:

SoC- Start of Cycle

PReq- Poll Request

Pres- Poll Response

SoA- Start of Async

POWERLINK Cycle :

Start Period : MN sends SoC frame to all devices.

Isochronous phase : MN issues PReq to poll CN to which CN

responds with Pres message.

Asynchronous phase: Transfer of non-time critical data packets (Eg:

parameterization data)

ETHERNET Frame Format :

MAC Header- Destination MAC address, Source MAC address and

Ethertype (0x88AB for POWERLINK).

Ethernet Payload- Usually between 46 and 1500 Bytes.

CRC trailer- Cyclic Redundancy Check.

POWERLINK Frame Format :

POWERLINK Header- Destination address, Source address and

Message Type.

POWERLINK Payload

POWERLINK Message Types :

SoC, PReq, PRes, SoA, ASnd, AMNI and AInv

POWERLINK Node Addressing :

In a network, nodes are addressed via a 8 bit node ID.

Object Dictionary :

Structured List of Objects.

Interface between node’s application and the network.

Objects in OD accessed via SDO and PDO Service.

Object :

Defines an Interface between the application and other network

participants.

Further divided into sub objects.

Object Attributes :-

Index – 16 bit unsigned integer.

Sub Index – 8 bit, 00h contains number of array/record entries

and FFh describes structure of object.

Object type – 7 – VARIABLE (Single Value, No Sub objects)

8 – ARRAY (Array of values of the same data type, entries are given as

sub objects)

9 – RECORD (Structure of values of different data types, entries are

given as Sub-objects)

Data Type – 16 Bit Unsigned Integer to indicate data type. 0001h – BOOLEAN

0002h – INTEGER8

0003h - INTEGER16

0004h – INTEGER32

0015h – INTEGER64

0005h – UNSIGNED8

0006h – UNSIGNED16

0007h – UNSIGNED32

0008h – REAL32

0009h – VSTRING

000Ah – OSTRING

000Fh – DOMAIN

Value Range: The boundaries of the Data Type.

Access Type : const - The object's value is pre-defined and cannot change during

runtime. The object can only be read from network and node side.

ro - The object is read-only from the network side. The node itself can

change the value during runtime.

wo - The object is write-only from the network side. The node itself can

only read the value during runtime.

rw - The object is read-write from the network side. Also the node

itself can read and write a value from/to the object.

PDO Mapping : no - The object cannot be mapped to a PDO.

default - The object is mapped by default to a PDO.

RPDO - The object may be mapped to an RPDO.

TPDO - The object may be mapped to a TPDO.

optional - The object may be mapped to either RPDO or TPDO.

Default Value: The default value determines the value of the

object when it is unconfigured.

Actual Value: From the network side, the actual value of the

object is retrieved via SDO read command or via mapping the

object to a TPDO. The actual value of the object can be set via

SDO write command or via mapping the object to an RPDO.

Object Dictionary Organization :

Sections

Data type definition area

Communication profile area

Manufacturer specific profile area

Device profile specific area

Interface profile specific area

Service Data Objects (SDO) :

Based on client server principle.

Client establishes connection with server and issues specific

commands.

Connection is unicast and not deterministic.

Asynchronous Phase in POWERLINK.

Process Data Objects (PDO) :

Specific Data that needs to be sent frequently and many

participants of the network may be interested in the same data.

Transmitting Node creates a Transmit PDO and Receiving Node

creates a Receive PDO.

Isochronous Phase in POWERLINK.

The process of assembling the TPDOs and RPDOs is called PDO

Mapping.

RASPBERRY PI 2

Features:

Not a Microcontroller but a LINUX Computer!

The processor: 900MHz quad-core ARM Cortex-A7 CPU and 1 GB RAM.

Secure Digital (SD) card slot: No hard drive on the Pi, Therefore everything

stored on a SD card.

HDMI Port

Ethernet Port: RJ45 Port

Combined 3.5mm audio jack and composite video

Camera interface (CSI)

Display interface (DSI)

Micro SD card slot

VideoCore IV 3D graphics core

Indicator LEDs:

ACT – (Green) – Lights when SD card is accessed. PWR – (Red) – Hooked up to 3.3V Power Supply FDX – (Green) – On if network adapter is full duplex LNK – (Green) – Network Activity Light 100 – (Yellow) – On if the network connection is 100Mbps

General Purpose Input Output (GPIO) pins:

Read buttons, switches and input signals and also control actuators

like LEDs, motors and Relays at Outputs.

40 GPIO Pins on the board.

Power Draw:

Without HDMI, GRAPHICS and ETHERNET, Pi2 draws 200mA

current.

Ethernet draws about 40mA current.

Heavy Computational components draw 200-250mA.

Overall, Raspberry Pi2 draws a current of around 650mA.

OpenPOWERLINK

Open Source Industrial Ethernet Stack implementing the POWERLINK

protocol for MN and CN.

Implements Modes of Operation :

Standard

Multiplexed

Poll Response Chaining

Dynamic and Static PDO mapping

SDO via Asynchronous Send (ASnd) and SDO via UDP

Asynchronous Communication via a Virtual Ethernet Interface.

OpenPOWERLINK with RASPBERRY PI 2

Setting up UBUNTU Linux on the RaspberryPi 2 Boards:

Slot SD Card in the SD Card Reader connected to windows PC.

Write the UBUNTU Disk Image File into the SD card using Windows

Disk Imager.

The Peripherals are connected to the RaspberryPi board, it is powered

on and logged in as user ‘linaro’.

The oplk_Pi.zip, wiringPi package, packet capture (pcap) libraries,

dependency files and Install_pcap.sh file are copied into a USB Thumb

drive.

The USB Thumb Drive is mounted, the contents copied to the home

folder and the zipped oplk_Pi is unzipped.

POWERLINK packet capture and its dependencies are installed.

The openPOWERLINK Master binaries are run and the Ethernet Interface

is chosen as ‘eth0’.

The openPOWERLINK Slave binaries are run and the Ethernet Interface is

chosen as ‘eth0’.

The POWERLINK Network is running when master displays

“NmtCsOperational” and slave displays “NmtEventStartNode”.

Testing :

When HIGH (3.3V) is given to Pin 11 of MASTER, Pin 11 of Slave will

also be HIGH.

When LOW (Gnd) is given to Pin 11 of MASTER, Pin 11 of Slave will

also be LOW.

Application developed for RaspberryPi2 Kit

MASTER:

Controlling the Enabling and Direction of

rotation of motor in Slave 2.

Changing the pattern of the lights in Slave 1.

Indicators for Stack Shutdown, Standby Mode

and Application Running.

Indication for Slave operational state.

SLAVE 1:

Four LEDs glowing in pattern controlled from the

master.

Emergency Push Button – to stop the application

when pressed and send an indication to the

master.

SLAVE 2:

Motor connected with a L293D Motor driver,

controlled by the inputs from the master.

Four LEDs brightness varying according to the

Motor’s speed (PWM).

RaspberryPi2 Kit Setup Drawing

CAD Drawing of the setup including:

Three RaspberryPi2 Boards

Three application Dot matrix boards

D-Link Switch

SIEMENS Lights for indicators

Emergency Push Button

Motor

Remotely connecting RPi2 Boards

The Raspberry Pi 2 boards are remotely connected

via SSH using PUTTY.

Static IP addresses are set for the boards:

sudo vi /etc/network/interfaces

iface eth0 inet static

address –

netmask -

In the application setup, the master’s address is

192.168.1.240, slave 1 is 192.168.1.1 and slave 32 is

192.168.1.32.

While connecting via SSH, the IpV4 connection

settings also have to be changed to a static IP and

netmask.

Observations while making application

Xap.h is a file generated by openConfigurator and it

contains the details of the Object attributes.

Xdd file is the device description file given by the

board manufacturer.

Mnobd.c file contains details of the packet size and

PDO mapping.

A maximum of 239 slaves are possible in

POWERLINK network.

pProcessImageIn is directed from master to slave

and pProcessImageOut is from slave to master.

Processing time in processsynq() function has to be

within the cycle time of the network, so delay()

should be avoided.

openPOWERLINK with XILINX ZYNQ

For building openPOWERLINK for ZYNQ SoC, Build

steps to be carried out:

Build Hardware Platform

Build the openPOWERLINK Stack Libraries

Build the drivers

Build the application

Build the zynq bootloader

Building Hardware Platform:

Build the hardware library of MicroBlaze using

cmake

Build platform with driver libraries set to debug.

Make and then make install

Build platform with driver libraries set to release.

Make and then make install

Repeat the same steps for Xilinx ZynqArm

The difference between Debug and Release modes is that

the print statements will be executed in Debug mode but

not in release mode.

Building Stack Libraries:

For Microblaze, choose appropriate compile

libraries and library path from configuration

options.

Cmake compiling in Debug and Release modes.

Repeat same steps for ZynqArm

Building Drivers:

Install PCP Daemon for Microblaze only.

While compiling using cmake, include the lines in

the command –

-DCFG_HW_LIB=”Xilinx-Z702//mn-dual-shmem-

gpio

-DCFG_BUILD_KERNEL_STACK=”PCP Daemon

Dual_Proc …

Building a Demo Application:

Build only for target ZynqArm

The build type in cmake could be either debug or

release.

Building Bootloader:

Create an executable bootloader and cmake

compiling in either debug or release mode.

The generated BOOT.bin file:

The output in Tera Term: