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TEXAS INSTRUMENTS
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CC2431DK
Technical data
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TEXAS INSTRUMENTS CC2431DK Technical data

CC2431
CC2431DK
Development Kit
User Manual
Rev. 1.5
CC2431
Table of contents
1.
INTRODUCTION......................................................................................................................4
2.
ABOUT THIS MANUAL ..........................................................................................................4
3.
DEFINITIONS............................................................................................................................4
4.
CC2431DK CONTENT..............................................................................................................5
5.
SYSTEM OVERVIEW..............................................................................................................6
5.1 G
5.2 N
5.2.1 Reference Node..................................................................................................................................................................... 7
5.2.2 Blind Node............................................................................................................................................................................. 7
5.2.3 Dongle................................................................................................................................................................................... 7
5.3 RSSI..............................................................................................................................................7
5.4 P
5.5 C
5.6 T
6.
6.1 C
6.2 E
7.
7.1 B
7.2 P
7.3 S
7.4 CC2430DB.................................................................................................................................16
8.
8.1 S
8.2 LEDS..........................................................................................................................................17
9.
9.1 O
9.2 I
9.3 C
9.4 I
10. GRAPHICAL USER INTERFACE........................................................................................20
10.1 M
10.1.1
10.2 S
10.2.1
10.2.2
10.2.3
10.2.4
10.3 T
11. NODES......................................................................................................................................25
10.1 B
11.1.1
11.1.2
11.2 R
11.3 L
12. MESSAGES..............................................................................................................................26
12.1 XY-RSSI R
12.2 XY-RSSI R
12.3 B
12.4 B
12.5 R
12.6 B
12.7 R
12.8 B
12.9 RSSI B
13. CONSTANTS IN SOFTWARE...............................................................................................29
RID
..............................................................................................................................................6
ODES
...........................................................................................................................................7
ROGRAM FLOW
OMMUNICATION FLOW
YPE DEFINITIONS
IAR EMBEDDED WORKBENCH PROJECT.....................................................................10
ONFIGURATIONS
MBEDDED SOFTWARE ARCHITECTURE
HARDWARE DESCRIPTION...............................................................................................13
ATTERY BOARD ROGRAMMING OF MART
RF04EB...........................................................................................................................16
NODES......................................................................................................................................17
ETUP/ START-UP
LOCATION ENGINE WINDOWS GUI................................................................................17
VERVIEW
NSTALLATION
ONNECTIONS
NTERACTION WITH OTHER NETWORK NODES
ENUS AND BUTTONS
Settings...................................................................................................................................................................... 21
ETTINGS PANELS
Setup.......................................................................................................................................................................... 22
Background............................................................................................................................................................... 22
Reference Node Setup............................................................................................................................................... 23
Blind Node Setup....................................................................................................................................................... 24
HE STATUS BAR
LIND NODE THEORY OF OPERATION
Polled Mode.............................................................................................................................................................. 25
Auto Mode................................................................................................................................................................. 26
EFERENCE NODE THEORY OF OPERATION OCATION DONGLE THEORY OF OPERATION
LIND NODE FIND REQUEST (CLUSTER
LIND NODE FIND RESPONSE (CLUSTER
EFERENCE NODE CONFIGURATION (CLUSTER
LIND NODE CONFIGURATION (CLUSTER
EFERENCE NODE CONFIGURATION REQUEST (CLUSTER
LIND NODE CONFIGURATION REQUEST (CLUSTER
LAST (CLUSTER
............................................................................................................................8
...............................................................................................................8
.........................................................................................................................8
........................................................................................................................10
......................................................................................11
........................................................................................................................13
SOC_BB.......................................................................................................14
........................................................................................................................17
..................................................................................................................................17
.............................................................................................................................18
.............................................................................................................................18
..............................................................................19
.................................................................................................................21
........................................................................................................................22
........................................................................................................................24
.............................................................................................25
.................................................................................26
..............................................................................26
EQUEST (CLUSTER ESPONSE (CLUSTER
ID: 0X0011)................................................................................26
ID: 0X0012)..............................................................................26
ID: 0X0013)..................................................................27
ID: 0X0014) ................................................................27
ID: 0X0015)......................................................27
ID: 0X0016)...............................................................28
ID: 0X0017).......................................28
ID: 0X0018) ...............................................28
ID: 0X0019)...........................................................................................28
CC2431
13.1 T
13.2 RSSI
14. SCHEMATICS.........................................................................................................................30
15. DOCUMENT HISTORY.........................................................................................................32
IMING CONSTANTS
AVERAGING CONSTANTS
....................................................................................................................29
....................................................................................................29
CC2431
1. Introduction
This CC2431DK User Manual describes how to use the software and hardware included in the CC2431 Development Kit.
Please refer to the Quick Start Guide for a brief introduction on how to get started using the development kit.
2. About this manual
This manual contains some of the theoretical material needed to develop a positioning system based on CC2431 and gives a brief introduction to the software provided in the kit.
3. Definitions
Blind Node A node using CC2431 and the Location Engine to calculate its
own position. Reference Node A node located on a static location. GUI Graphic User Interface Chipcon Packet Sniffer A PC tool to visualize traffic on radio Z-location Engine A PC tool used to configure and display location engine results RSSI Received Signal Strength Indicator TIMAC Texas Instruments Media Access Control, a SW protocol that
handles IEEE 802.15.4 data handling SOC_BB System on Chip Battery Board CC243xEM CC2430/ CC2431 Evaluation Module, a small plug-in module
for SmartRF04DK, should be used as reference design for RF
layout. CC2430-F128 CC2430 with 128 kB FLASH
CC2431
4. CC2431DK content
The development kit contains the following: 2 x SmartRF04EB
10 x SOC_BB (Battery Board) 2 x Evaluation Modules CC2430EM 10 x Evaluation Modules CC2431EM 12 x 2.4GHz Antennas 2 x USB cables 1 x RS232 Serial cable 1 x 10-wire flat cable for using SmartRF04EB as emulator for external target systems 1 x Quick start guide
SmartRF04EB with CC2430EM Battery board with CC2431EM
The SmartRF04DK Development Kit includes a sample application for location calculation and demonstration. The sample application allows you to:
• Evaluate the SmartRF can be used for range testing and location engine testing
• Use SmartRF easily configured to measure sensitivity, output power and other RF parameters.
• Develop and test your own firmware. The CC2431DK includes a USB interface that can be used as an emulator interface for the CC2430 or CC2431. All I/O ports are available on pin connectors on the edge of the board to allow easy access for testing or for external I/O.
®
Studio to perform RF evaluation and measurements. The radio can be
®
04 products. Apply power the boards and the plug and play kit
5. System overview
For an introduction to the location engine please see application note AN042,
document number SWRA095. The note is available from www.ti.com.
Blin
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CC2431
Figure 1: Location Estimation
The location algorithm used in CC2431 Location Engine is based on RSSI (Received Signal Strength Indicator) values. The RSSI value will decrease with increasing distance. An important parameter related to the performance of the location estimate is the absolute tolerance of the RSSI measurement of the RF-transceiver. This is specific to our transceiver and is provided in the datasheet. The main feature of the CC2431 Location Engine is that the location estimation is performed in each Blind Node, hence the algorithm is decentralized. This reduces the amount of data transferred on the RF interface, since only the calculated position is transmitted.
The location engine implemented in CC2431 can use up to 16 Reference Nodes for each calculation. The data that is necessary to do a calculation are X, Y and RSSI values for each of the Reference Nodes used in the system setup. In addition it needs two RF transmission parameters (A and N), please refer to application note AN042 for a description of each parameter.
5.1 Grid
To map each location to a distinct place in the natural environment, a two dimensional grid is used. The direction will, in the following, be named X and Y. The CC2431 Location Engine can only handle two dimensions, but it’s possible to handle a third dimension in software (i.e. to represent levels in a building). The point named (X, Y) = (0, 0) is located in upper left corner of the grid.
5.2 Nodes
The CC2431 Location Engine uses the RSSI value combined with the physical location of the Reference Nodes to calculate its own position.
Any number of Reference Nodes can be used in the system, but a node can only calculate its position if it is within range of at least three Reference Nodes
Experiments have shown that one Reference Node for each 100 m estimates. The nodes should be placed in a grid with one node for each 10 meters in both directions.
5.2.1 Reference Node
A node which has static location is called a Reference Node. This node must be configured with an X and a Y value that correspond to the physical location.
The main task for a Reference Node is to provide “reference” packets to the Blind Node. Reference packets contain the X and Y coordinates of the Reference Node.
5.2.2 Blind Node
A Blind Node will communicate with its nearest Reference Nodes, collecting X, Y and RSSI values for each of these nodes. Then it uses the location engine hardware to calculate its position based on the collected parameters from several Reference Nodes.
1
.
2
gives good location
CC2431
5.2.3 Dongle
The Dongle will communicate with the entire network; it can request or configure the X,Y values of all Reference Nodes and the A and N values of the Blind Nodes via the Z-location Engine PC Application. The Z-location Engine can also configure any Blind Node to automatically make a periodic position calculation and report (by default the Blind Node is waiting for a command to perform a position calculation.)
5.3 RSSI
The RSSI value is typically in the range -40 dBm to -90 dBm, where -40 dBm is the highest value. -40 dBm is approximately the measured signal strength on distance of one meter. Input to the location engine hardware is the absolute value of the RSSI in dBm, so the range will typically be from 40 to 90, where 40 is the highest signal strength.
1
Three is a lower theoretical limit, for a good estimate three Reference Nodes may be too
few.
5.4 Program flow
The program flow for both Reference Node and Blind Node are shown in Figure 2 and Figure
3. The figures are simplified.
CC2431
Figure 2: Reference Node Figure 3: Blind Node
5.5 Communication Flow
The Z-location Engine is configured to periodically query the entire network – the X,Y of all Reference Nodes is requested and all Blind Nodes are commanded to perform a position calculation. When a Blind Node performs a position calculation, the Over-the-Air (OTA) message traffic can be observed as three phases: broadcast, data collection, & position calculation and reporting.
Broadcast Phase
The Blind Node sends out a 1-hop broadcast to learn the network address of all Reference Nodes that are within radio range. Then the Blind Node sends out a blast of several 1-hop broadcast messages, and any Reference Node receiving such a message shall make a running average of the RSSI of the packets received from a particular Blind Node.
Data Collecting Phase
After the broadcast phase, the Blind Node will send a 1-hop unicast message to every Reference Node in radio range requesting the average RSSI calculated during the broadcast blast.
Position Calculating Phase
In this phase the Blind Node calculates the position and transmits it to the Dongle.
5.6 Type definitions
Some values are given in the notation: UINTTotalBits_FractionalBits, this means unsigned, total TotalBits number of bits, where FractionalBits number of bits represent the fraction part.
Example: UINT8_2 means unsigned, 8 bits with 2 fraction bits. This leaves 6 bit to the integer part.
Both “UINT8_1”, “UINT8_2” and “UINT16_2” are used in the source code.
Notation Max Accuracy
UINT8_1 127,5 0.5 meter UINT8_2 63,75 0.25 meter UINT16_2 16 383,75 0.25 meter
Table 1: Notation
CC2431
CC2431
6. IAR Embedded Workbench Project
The CC2431DK development kit is delivered with the software preprogrammed into the CC2431 on the evaluation modules. The location demo can be started right out of the box by following the instructions in the CC2431DK Quick Start Instructions included in the kit. The Quick start instructions can also be downloaded from the
The source code is described in this user manual as it gives a good understanding of how the location demo works.
6.1 Configurations
The remainder of this chapter describes how to set up a location network with 3 or more Reference Nodes and 1 or more Blind Nodes.
Download the from the CC2431 product page on
• TIMAC (Requires registration)
• Location engine example source code
• Z-location Engine PC application
Install the Z-location Engine and IAR Workbench. The Location engine example source code is provided as a sample application in the TIMAC.
To install the location sample source code in the right directory copy the zip file with the source code to C:\Texas Instruments\TI-MAC-1.1.0. Unzip the file and preserve file paths, this will copy the source files to C:\Texas Instruments\TI-MAC-1.1.0\Projects\mac\Location
Navigate to the IAR_Files project directory located at:
C:\Texas Instruments\TI-MAC-1.1.0\Projects\mac\Location\cc2430\IAR Project
Launch the IAR Embedded Workshop by double clicking on the SampleApp.eww file:
www.ti.com
CC2431 product web site.
Figure 4: Location Software Project Directory
In the location software workspace there exist three different project configurations:
• CC2430BB
• CC2430DB
• CC2430EB
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