Atmel STK512 User manual

5170C–AVR–10/09
STK512
....................................................................................................................
AVR-based Uni-directional
Radio Starter Kit Featuring
Secure Rolling-Code RF
Transmission Encryption
User Guide
Note: This Radio Starter Kit is not self-contained. It is based on an Atmel®AVR®STK®500
Flash Microcontroller Starter Kit that must be obtained separately.

STK512 User Guide i
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Table of Contents
Section 1
Introduction.................................................................................................................1-1
1.1 Purpose.............................................................................................................................. 1-1
1.2 General Description ........................................................................................................... 1-1
1.3 Evaluation Kit Features......................................................................................................1-1
1.4 Included in the Kit .............................................................................................................. 1-2
Section 2
Getting Started ...........................................................................................................2-1
2.1 Hardware Assembly........................................................................................................... 2-1
2.2 Initial Programming............................................................................................................ 2-6
2.2.1 Programming the ATmega88 to Control the Receiver......................................... 2-6
2.2.2 Programming the Transmitter(s).......................................................................... 2-7
2.3 Teach the Transmitters to the Receiver............................................................................. 2-8
2.4 The Demonstration ............................................................................................................2-9
Section 3
Programming Notes ...................................................................................................3-1
3.1 Configuration...................................................................................................................... 3-1
3.2 Project Compilation............................................................................................................ 3-2
3.3 EEPROM Image Generation.............................................................................................. 3-2
Section 4
Troubleshooting Guide...............................................................................................4-1

STK512 User Guide 1-1
5170C–AVR–10/09
Section 1
Introduction
Congratulations on your purchase of the Atmel®AVR®-based Uni-directional Radio Starter Kit featuring
Secure Rolling Code RF Transmission Encryption. This kit uses an Atmel STK®500 Flash Microcon-
troller Starter Kit that must be obtained separately.
This User’s Guide describes how to use this Starter Kit. Section 2, Getting Started, describes how to
assemble and program the hardware to demonstrate a wireless link that uses a secure rolling code algo-
rithm. Section 3, Programming Notes, describes optional programming for the advanced user.
1.1 Purpose
This starter kit demonstrates a Secure Rolling Code Algorithm transmission protocol for use in a unidi-
rectional wireless communication system. Typical applications for this algorithm are garage door
openers, remote keyless entry, passive entry, and remote car-start systems.
1.2 General Description
This kit demonstrates the transmission protocol with one receiver and a pair of associated transmitters.
However, a typical system can support many more transmitters.
Characteristics of this protocol are:
A transmission-encryption value that is valid only once, preventing interception and re-transmission to
gain unauthorized access,
Message content that is virtually impossible to predict, even if previous messages are known.
For a thorough technical coverage of the hardware, software, and theory, read the application note,
“AVR411: Secure Rolling Code Algorithm for Wireless Link” that is included on the accompanying CD.
1.3 Evaluation Kit Features
Advanced Encryption Standard (AES) and its Cipher-based Message Authentication Code (CMAC)
mode of operation for transmitter authentication:
Multiple transmitters supported
PC command-line tools for cryptographic key management
Up to 256-bit key sizes supported
Less than 30 ms response time
315/434/868 MHz ISM-band frequencies
ATA5771/73/74 and ATA8741/42/43 UHF ASK/FSK transmitters with embedded ATtiny44
microcontroller

Introduction
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ATA5723/24/28 and ATA8203/04/05 UHF ASK/FSK receivers
User-programmable transmitters with 6-pin ISP
Sleep modes for minimal power consumption
1.4 Included in the Kit
Note: This Radio Starter Kit is not self-contained. It is based on an Atmel STK500 Flash Microcontroller Starter
Kit that must be obtained separately.
This starter kit includes all the essential components needed to demonstrate an AVR-based uni-direc-
tional radio that features a Secure Rolling-Code RF Transmission Encryption protocol. Contents of this
kit are listed and shown in Figure 1-1.
Transmitter application board
ISP programming adapter for Transmitter
Receiver application board with external antenna
STK512 Interface Board
ATMega88 microcontroller (not shown)
CDROM containing software, Data Sheets, and other documentation (not shown)

Introduction
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Figure 1-1. Kit Contents
For investigating further capabilities of this kit, the following are optional:
JTAGICE mkII for debugging
IAR Embedded Workbench®AVR C compiler for changing and recompiling the source code without
porting it to another compiler (precompiled source code with default configuration is provided on the
CDROM).

STK512 User Guide 2-1
5170C–AVR–10/09
Section 2
Getting Started
This section contains the steps required to get a simple system with a receiver and two transmitters up
and running. Hardware assembly, initial programming of the components, teaching the transmitters to
the receiver, and demonstrating the transmission protocol are described in the following subsections.
2.1 Hardware Assembly
The kit hardware must be interfaced to the STK500.
Step A: Assemble the STK500 Board
The STK500 Board must be set up properly before mounting the STK512 Interface Board. The assem-
bled STK500 Board is shown in Figure 2-1.
Figure 2-1. STK500 Board with Ribbon Cables and Microcontroller

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1. Carefully remove any ICs in the green “SCKT3200A2” socket.
2. Insert the furnished ATMega88 into the “SCKT3200A2” socket.
Note: The orientation of the red stripe in the cable is not critical in the following steps as long as pin 1 is con-
nected to pin 1.
3. Using a 6-pin jumper cable supplied with the STK500;
connect the two male headers “ISP6PIN” and “SPROG2”.
4. Using a 10-pin jumper cable supplied with the STK500;
connect the two male headers “PORTC” and “LEDS”.
5. Using a 10-pin jumper cable supplied with the STK500;
connect the two male headers “PORTD” and “SWITCHES”.
6. Place jumpers on the following headers as shown in Figure 2-2.
–VTARGET
–AREF
– RESET
–XTAL1
– OSCEL (a 3-pin header. Place a jumper next to the “1” printed on the board).
Figure 2-2. Detail of Jumper Placement on the STK500

Getting Started
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Step B: Assemble and Attach the STK512 Interface Board
The STK512 Interface Board must be assembled and mounted on the STK500 Board. The completed
assembly is shown in Figure 2-3.
Figure 2-3. Assembled STK512 Interface Board
1. Orient the STK500 as shown in the Figure 2-3.
Caution: After the next step, whenever the interface board is removed from the STK500 sockets, use
caution if a tool is used for leverage. It is easy to bend pins or otherwise damage the STK500 and/or the
interface board. Use a rocking motion while steadily pulling (not prying) it straight from the sockets.
2. Insert the STK512 Interface Board into the EXPANDx sockets, oriented with the LEDs and red DIP
switches to the left-hand side. To verify the orientation, check that the EXPAND0 pins on the Inter-
face Board plug into the EXPAND0 socket on the STK500 Board. Press firmly so that the board pins
seat well.
3. Install jumpers on all five pairs of pins (JP2, next to the “configure” button) as shown in Figure 2-4.

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Figure 2-4. STK512 Jumper Placement

Getting Started
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Step C: Mount the Receiver Application Board
The Receiver Application Board must be mounted on the STK512 Interface Board. The completed
assembly is shown in Figure 2-5.
Figure 2-5. Completed Receiver Assembly
Caution: After the next step, if the receiver board is removed from the interface board sockets, use
EXTREME caution! The pins on the receiver board are very easily bent and broken! Use a rocking
motion to lift the board straight (perpendicular) out of the socket.
1. Orient the receiver board above the Interface Board as shown in Figure 2-5. Carefully insert the
Receiver Application Board into the STK512 Interface Board sockets.
2. Install the antenna onto the SMB connector.
3. Supply the STK500 with +12 V power by connecting it to a PC using the RS232 port.