Atmel AVR2016 User manual

APPLICATION NOTE
Atmel AVR2016: RZRAVEN Hardware User’s Guide
8-bit Atmel Microcontrollers
Features
•Development kit for the Atmel®AT86RF230 radio transceiver and Atmel AVR®
microcontroller
•CE, ETSI and FCC approved
•LCD module (Atmel AVRRAVEN):
•AT86RF230 radio transceiver with high gain PCB antenna
•Dual AVR microcontrollers
•Dynamic speaker and microphone
•Atmel Serial Dataflash®
•User I/O section:
•USART
•GPIO
•Relay Driver
•Powered by battery or external supply:
•5V to 12V external supply
•USB module (Atmel RZUSBSTICK):
•AT86RF230 radio transceiver with miniature PCB antenna
•AVR microcontroller with integrated Full Speed USB interface
•External memory interface
Introduction
The Atmel RZRAVEN is a development kit for the AT86RF230 radio transceiver and
the AVR microcontroller. It serves as a versatile and professional platform for
developing and debugging a wide range of RF applications; spanning from: simple
point-to-point communication through full blown sensor networks with numerous
nodes running complex communication stacks. On top of this, the kit provides a nice
human interface, which spans from PC connectivity, through LCD and audio input
and output.
Figure 1. The RZRAVEN kit modules.
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Table of Contents
1.General 3
2.The Atmel AVRRAVEN module ...........................................................4
2.1Atmel AVR Microcontrollers .............................................................................. 5
2.2Atmel Radio Transceiver................................................................................... 5
2.3Antenna description .......................................................................................... 5
2.4LCD ............................................................................................................... 5
2.5Speaker............................................................................................................. 5
2.6Microphone ....................................................................................................... 6
2.7Serial Dataflash................................................................................................. 6
2.8Serial EEPROM ................................................................................................ 6
2.9Real Time Clock................................................................................................ 6
2.10NTC ............................................................................................................... 6
2.11Power supply..................................................................................................... 6
2.12Interfaces .......................................................................................................... 7
2.12.1Programming Interface ....................................................................... 8
2.12.2Relay Interface.................................................................................... 9
2.13Voltage Measurement Interface ........................................................................ 9
2.13.1GPIO……………………………………………………………………….. 9
3.The Atmel AVR RZUSBSTICK Module..............................................10
3.1AVR Microcontroller ........................................................................................ 11
3.2Atmel Radio Transceiver................................................................................. 11
3.3Antenna description ........................................................................................ 11
3.4Interfaces ........................................................................................................ 11
3.4.2External Memory Interface................................................................ 12
3.4.3Serial Interface.................................................................................. 12
3.4.4Programming Interface ..................................................................... 12
3.4.5LEDs……………………………………………………………………….12
Appendix A.Atmel AVRRAVEN Schematics
.....................................13
Appendix B.Atmel AVRRAVEN Bill of materials ...............................18
Appendix C.Atmel AVRRAVEN LCD ................................................20
Appendix D.Atmel RZUSBSTICK Schematics ..................................22
Appendix E.Atmel RZUSBSTICK Bill of materials ............................23
Appendix F.Federal Communications Commission (FCC) Statement24
F.1FCC Statements.............................................................................................. 24
F.1.1Equipment usage.............................................................................. 24
F.1.2Compliance Statement (Part 15.19).................................................. 24
F.1.3Warning (Part 15.21)......................................................................... 24
F.1.4Compliance Statement (Part 15.105(b)) ........................................... 24
F.1.5FCC IDs ........................................................................................... 24

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1. General
The Atmel RZRAVEN kit is built from one Atmel RZUSBSTICK module and two AVRRAVEN modules. See Figure 1-1
to Figure 1-4 for further details.
The complete schematics and Gerber files are available from the compressed archive accompanying this application
note.
Figure 1-1. Assembly drawing AVRRAVEN – front view.
Figure 1-2. Assembly drawing AVRRAVEN – back view.

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Figure 1-3. Assembly drawing Atmel RZUSBSTICK – front view.
Figure 1-4. Assembly drawing RZUSBSTICK – back view.
2. The Atmel AVRRAVEN module
Figure 2-1. AVRRAVEN overview.
The AVRRAVEN hardware is based on two microcontrollers and one radio transceiver chip. The Atmel ATmega3290P
handles the sensors and the user interface and the Atmel ATmega1284P handles the Atmel AT86RF230 radio
transceiver and the RF protocol stacks. The MCUs and the radio communicate via serial interfaces.
For hardware details please refer to Appendix A for the complete AVRRAVEN schematics.

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2.1 Atmel AVR Microcontrollers
Two AVR microcontrollers are found on the Atmel AVRRAVEN module. An Atmel ATmega1284P is connected to the
Atmel AT86RF230 radio transceiver, and an Atmel ATmega3290P is driving the LCD. Both these devices are selected
from the AVR picoPower®family, something that ensures minimal power consumption and operation down to 1.8V.
Universal Synchronous and Asynchronous serial Receiver and Transmitter (USART) is used as an inter processor
communication bus.
2.2 Atmel Radio Transceiver
The AT86RF230 is a 2.4GHz radio transceiver that is tailored for a wide range of wireless applications. Low power
consumption and market leading RF performance makes it an excellent choice for virtually any type of networking
device. Support for IEEE®802.15.4 TM (Automatic acknowledge of packets, address filtering and automatic channel
access) type of applications is available through an enhanced layer of functionality on top of the basic radio transceiver.
2.3 Antenna description
The antenna on the AVRRAVEN is a 100loop antenna with a net peak gain of about 5dB.
2.4 LCD
The LCD found on the AVRRAVEN module is a full custom 160-segment display tailored for the Atmel RZRAVEN kit
(See Figure 2-2 for a quick reference). It contains a seven segments text area; four segment number area and
numerous handy symbols. In particular pay attention to the bird looking symbol. It is symbolizing the two black scouting
ravens of Norse god Odin; Hugin (Thought) and Munin (Memory). The saga says that they flew around the world and
reported news back to Odin at night. Underneath the raven segment’s “eye” there is a red LED capable of soft-blinking;
this may be used to indicate the AVRRAVEN’s search for “news” on the air interface.
A full segment map can be found in Appendix C and in the schematics folder in the compressed archive file
accompanying this application note. The LCD is driven directly from the connected ATmega3290P.
Figure 2-2. AVRRAVEN – LCD Segments.
2.5 Speaker
An 8speaker is provided. The ATmega3290P controls all audio. The signal source is the TIMER1’s PWM output and
the signal is shaped via a low-pass filter and amplified by a Class-D amplifier. Pulling PORTE7 low activates the active
filter and providing a PWM signal on PORTB5 activates the amplifier.

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2.6 Microphone
The Atmel AVRRAVEN’s microphone is connected to the Atmel ATmega3290P ADC channel 0. The signal is amplified
and low-pass filtered. Pulling PORTE7 low activates the microphone circuit.
2.7 Serial Dataflash
A 16Mb Atmel Serial Dataflash (AT45DB161D) is connected to the ATmega3290P’s Serial Peripheral Interface (SPI).
This storage is used for safe firmware images, sounds and general-purpose parameters. See the firmware
documentation for an overview of occupied sectors, and those available to the end user. Even with a couple of safe
firmware images for the two microcontrollers there is plenty space left for the end user. Please note that the serial
Dataflash will operate properly when the voltage is above 2.5V while the rest of the design will operate down to 1.8V.
2.8 Serial EEPROM
A 2kb Atmel Serial EEPROM (AT24C02B) is connected to the Atmel ATmega1284P’s two-wire interface (TWI). This
storage is write protected by hardware and can only be read. The storage contains important configuration and
calibration data that should not be unintentionally overwritten. Information such as a unique EUI 64-bit address can be
found her-in. A rich set of access functions and the parameter map is given in the RZRAVEN firmware documentation.
2.9 Real Time Clock
Separate 32768Hz clock crystals are connected to the ATmega3290P’s and the ATmega1284P’s asynchronous timer
interfaces. This allows an application to implement a real time clock (RTC) to keep track of time when sleep modes are
used to reduce the power consumption. This is especially important for battery-operated nodes.
2.10 NTC
An NTC is connected to the ATmega3290P’s Analog to Digital Converter (ADC) channel 4. This NTC can be used to
measure the temperature in the surroundings of the AVRRAVEN. The NTC can be found below the joystick, close to
J401. The JTAG interface must be disabled when using the temperature sensor. When running the AVRRAVEN from
an external power source the onboard voltage regulator may heat the temperature sensor giving faulty reading. To
avoid this the sensor NTC may be soldered off and relocated using short wires. If a higher level of accuracy is required
the users may also calibrate the sensor by adjusting the temperature lookup table in firmware.
2.11 Power supply
The AVRRAVEN can be powered either from batteries or an external 5V to 12V DC source. The power source is
selected by the position of the jumper located immediately to the right of the LCD (See Figure 2-3 for a reference).
Polarity protection is provided when using an external power source.

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Figure 2-3. Power source selection.
The Atmel AVRRAVEN has been designed to run from two 1.5V LR44 battery cells.
An onboard voltage regulator makes it possible to run power the AVRRAVEN from a 5V to 12V DC source. The external
voltage is applied to the two leftmost pins in the user I/O area (J401). The Atmel ATmega3290P’s ADC channel 2 is
connected to a voltage divider and the external voltage supply interface. This way it is possible for the application to
monitor the external operating voltage.
2.12 Interfaces
The AVRRAVEN module has multiple interfaces that can be used for serial communication, interaction with external
sensors and control units such as relays and of course programming and debugging.

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Figure 2-4. AVRRAVEN User Interfaces.
Table 2-1. Interfaces available on J401.
Pin number Function Comment
1 Ext. power supply, 5-12V input External power input
2 Ext. power supply 0V Connected to internal 0V
3 Relay coil positive Relay driver circuit positive
4 Relay coil negative Relay driver circuit negative
5 Voltage measure input, 0-VCC*5 Analog input via 47k/10k voltage divider
6 Voltage measure input, 0-VCC Analog input directly to ADC input.
7 VCC Connected to the VCC net directly
8 User I/O #1 Digital I/O, may interface an LED or a switch directly. On-board 470
series resistors and 10kpull-ups are provided.
Pin change interrupts, TWI and USI is also available on these pins.
9 User I/O #2
10 User I/O #3
11 User I/O #4
12 Common Connected to internal 0V
Care should be taken when connecting to the Atmel AVRRAVEN’s interfaces, since there is no protection circuitry
provided. Damage to the MCUs or other circuits may be the result of ESD spark, short circuits, polarity or over-voltage
faults.
2.12.1 Programming Interface
Both the Atmel ATmega3290P and Atmel ATmega1284P can be programmed using either the JTAG or ISP interface.
JTAG programming can be facilitated by connecting a JTAG ICE mkII to the 50-mil pin header J301 (ATmega3290P)
and J204 (ATmega1284P). A total of 5 50-mil pin headers and one 50-mil to 100-mil converter are supplied with the
RZRAVEN kit.

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ISP programming can be performed by connecting an ISP enabled Atmel AVR programming tool to the pin header J302
(ATmega3290P) and J205 (ATmega1284P). AVR tools like Atmel STK®500, AVRISP mkII and JTAGICE mkII can be
used for this.
The AVRRAVEN does not come with these headers mounted. So it is up to the user populating these. Wires could also
be soldered in instead of the dual row headers.
2.12.2 Relay Interface
A relay interface (Relay Positive and Negative) is available through J401. This interface can be used with the
AVRRAVEN running from external power. A switching transistor is connected to PB6 on the ATmega3290P so that
sufficient current can be provided to the relay being driven. An external power source must be used if the relay option is
required. The AVRRAVEN must then be supplied with the rated voltage of the relay.
2.13 Voltage Measurement Interface
Two of the pins in header J401 can be used for external voltage measurements, however only one at the time. The
possible voltage ranges are 0 to VCC or via a voltage divider giving an approximate range of 0 to five times VCC. A
simple voltage divider is implemented to scale the measurement voltage. A diode bridge is also used to prevent reverse
polarity and to protect the ATmega3290P’s ADC channel 3.
2.13.1 GPIO
Both the Atmel ATmega3290P and Atmel ATmega1284P are high pin count devices, and a number of these are not
used. These pins are available through the user I/O headers; J401, J201, J202 and J203. See Table 2-2 and Table 2-3
for further details.
Be aware that these pins do not have level converters and should thus not be connected directly to an application board
running on a different voltage level than the Atmel AVRRAVEN.
Table 2-2. ATmega3290P User I/O.
ATmega3290P Port Pin PCB Connection Comment
PE3 J401-8 Via 470series resistor and10kpull-up
PE4 J401-9 Via 470series resistor and10kpull-up
PE5 J401-10 Via 470series resistor and10kpull-up
PE6 J401-11 Via 470series resistor and10kpull-up
Table 2-3. ATmega1284P User I/O.
ATmega1284P User I/O PCB Connection Comment
PC0 J201-1 TWI SCL.
Connected to serial EEPROM
PC1 J201-2 TWI SDA.
Connected to serial EEPROM
PC2 J201-3 JTAG TCK.
PC3 J201-4 JTAG TMS.
PC4 J201-5 JTAG TDO.
PC5 J201-6 JTAG TDI.
N.C. J201-7 Populate R204 to connect to PC6. RTC Xtal XC202 must then be
removed.

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ATmega1284P User I/O PCB Connection Comment
N.C. J201-8 Populate R205 to connect to PC6. RTC Xtal XC202 must then be
removed.
PD0 J202-1 RXD0 Inter processor communication.
PD1 J202-2 TXD0 Inter processor communication.
PD2 J202-3 DIO or RXD1.
PD3 J202-4 DIO or TXD1.
PD4 J202-5 DIO.
PD5 J202-6 DIO.
PB2 J202-7 DIO. NB: NOT PD6!
PD7 J202-8 DIO.
PA0 J203-1 DIO or ADC Channel 0.
PA1 J203-2 DIO or ADC Channel 1.
PA2 J203-3 DIO or ADC Channel 2.
PA3 J203-4 DIO or ADC Channel 3.
PA4 J203-5 DIO or ADC Channel 4.
PA5 J203-6 DIO or ADC Channel 5.
PA6 J203-7 DIO or ADC Channel 6.
PA7 J203-8 DIO or ADC Channel 7.
Additional interfaces PCB Connection Comment
ATmega1284P Port Pin PCB Connection Comment
External power J201-10
J202-10
J203-10
Connectec to J401-1
0V J201-9
J202-9
J203-9
Connected to J401-2
3. The Atmel AVR RZUSBSTICK Module
Figure 3-1. RZUSBSTICK overview.
PCB Antenna

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The AVR RZUSBSTICK hardware is based a USB microcontroller and a radio transceiver chip. The Atmel
AT90USB1287 microcontroller handles the USB interface, the Atmel AT86RF230 radio transceiver and the RF protocol
stacks.
For hardware details please refer to Appendix D for the complete AVR RZUSBSTICK schematics.
3.1 AVR Microcontroller
The Atmel AT90USB1287 is a device in the family of AVRs with a low and full speed USB macro with device, host and
On-the-go (OTG) capabilities.
3.2 Atmel Radio Transceiver
The AT86RF230 is a 2.4GHz radio transceiver that is tailored for a wide range of wireless applications. Low power
consumption and market leading RF performance makes it an excellent choice for virtually any type of networking
device. Support for IEEE 802.15.4 (Automatic acknowledge of packets, address filtering and automatic channel access)
type of applications is available through an enhanced layer of functionality on top of the basic radio transceiver.
3.3 Antenna description
The antenna on the RZUSBSTICK is a folded dipole antenna with a net peak gain of 0dB.
3.4 Interfaces
Figure 3-2. RZUSBSTICK Interfaces – front.
Figure 3-3. RZUSBSTICK Interfaces – back.

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3.4.2 External Memory Interface
When necessary the Atmel AT90USB1287’s 8kB of internal SRAM can be extended through the AVR external memory
interface. The suggested external SRAM is 32kB and is available from address 0x8000 to 0xFFFF giving a total of 40kB
when assembled.
Suggested latch and RAM:
•74AHC573PW
•BS62UV256TCP-10
3.4.3 Serial Interface
The USART on the Atmel AT90USB1287 is routed to J4 on the Atmel RZRAVEN’s backside. J4 is implemented as
three large pads (RX-TX-GND) where the user can solder in wires and route the signal to his or her preference. The
RX-TX signals are TTL level, so an external level converter must be connected if RS232 levels are necessary.
3.4.4 Programming Interface
A JTAG interface is provided for the AT90USB1287 microcontroller. The interface is available through a 50-mil spaced
10-pin dual row header. The RZRAVEN does not come with the header mounted. So it is up to the user populating it.
Wires could also be soldered in instead of the dual row headers. A total of 5 50-mil pin headers and one 50-mil to 100-
mil converter are supplied with the RZRAVEN kit.
3.4.5 LEDs
Four LEDs are assembled on the board:
Table 3-1. Atmel AT90USB1287 LEDs.
LED AT90USB1297
Port Pin
Comment
Blue (D1) PORTD7 Turn LED on by pulling port pin high
Red (D2) PORTD5 Turn LED on by pulling port pin low
Green (D3) PORTE7 Turn LED on by pulling port pin low
Orange (D4) PORTE5 Turn LED on by pulling port pin high

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Appendix A. Atmel AVRRAVEN Schematics

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Appendix B. Atmel AVRRAVEN Bill of materials
Qty Designator Description Manufacturer Part#
5 C205, C206, C207, C220,
C221
Ceramic capacitor, SMD 0402, NP0, 50V,
±0.25pF
1.2p
2 C201, C204 Ceramic capacitor, SMD 0402, NP0, 50V,
±5%
12p
3 C413, C414, C415 Ceramic capacitor, SMD 0402, NP0, 50V,
±10%
100p
1 C404 Ceramic capacitor, SMD 0402, X7R, 25V,
±10%
4.7n
14 C208, C301, C405, C407,
C408, C409, C410, C411,
C412, C416, C417, C420,
C421, C503
Ceramic capacitor, SMD 0402, X7R, 25V,
±10%
10n
2 C502, C504 Ceramic capacitor, SMD 0805, Y5V, 10V, -
20/+80%
4.7u
12 C211, C212, C213, C214,
C215, C303, C304, C305,
C306, C307, C418, C501
Ceramic capacitor, SMD 0402, X7R, 16V,
±10%
Kemet C0402C104K4RACTU
10 C202, C203, C209, C210,
C302, C401, C402, C403,
C406, C505
Ceramic capacitor, SMD 0402, X5R, 6.3V,
±10%
Kemet C0402C105K9PAC
4 R201, R208, R209, R415 Thick film resistor, SMD 0402, 1/16W, 1% 0R
7 R203, R306, R425, R427,
R428, R430, R434
Thick film resistor, SMD 0402, 1/16W, 1% 470R
5 R303, R401, R404, R405,
R417
Thick film resistor, SMD 0402, 1/16W, 1% 1k
1 R502 Thick film resistor, SMD 0402, 1/16W, 1% 1.5k
7 R304, R411, R412, R413,
R414, R432, R435
Thick film resistor, SMD 0402, 1/16W, 1% 3k
1 R410 Thick film resistor, SMD 0402, 1/16W, 1% 3.3k
17 R202, R206, R210, R211,
R212, R301, R302, R307,
R402, R406, R407, R408,
R421, R422, R423, R424,
R503
Thick film resistor, SMD 0402, 1/16W, 1% 10k
1 R305 Thick film resistor, SMD 0402, 1/16W, 1% 47k
10 R308, R309, R310, R409,
R416, R419, R426, R429,
R501, R504
Thick film resistor, SMD 0402, 1/16W, 1% 100k
3 R403, R418, R420 Thick film resistor, SMD 0402, 1/16W, 1% 470k
1 R431 NTC Thermistor 100kOhm Murata NCP18WF104J03RB
2 L401, L402 SMD RF inductor 0805 Murata BLM21PG300SN1D
2 L201, L501 SMD RF inductor 0805. Murata BLM21AG102SN1D
2 L202, L203 RF Inductor, 2.7nH, 0,17ohm, 300mA, 0402 Johanson
Technology
L-07C2N7SV6T
3 D401, D403, D408 Dual Schottky diode ST BAT54SWFILM
1 D501 Dual Schottky diode Philips 1PS70SB15
1 D404 Bidirectional Transient suppression diode,
600W
ST SM6T12CA

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Qty Designator Description Manufacturer Part#
1 Q501 General purpose SMD BJT dual NPN-PNP Philips BC847BPN
1 U303 16Mb 2.7-3.6 volt DataFlash ATMEL AT45DB161D-SU
1 U201 2.4GHz ZigBee/802.15.4 tranceiver ATMEL AT86RF230-ZU
1 U203 2kb Serial (TWI) EEPROM, AT24C02B,
1.8-5V
ATMEL AT24C02B-TSU-T
1 U501 LDO 3.3V 150mA SOT23-5 (cer. cap) Texas
Instruments
LP2985A-33DBV
1 U402 LMV934MT 1V8 Quad National
Semiconductor
LMV934MT
1 U204 AVR 8-bit RISC MCU ATMEL ATmega1284PV-10MU
1 U301 AVR 8-bit RISC MCU ATMEL ATmega3290PV-10AU
1 U403 TS2007 3W class D audio amp. ST TS2007IQT
2 XC202, XC301 32.768kHz SMD crystal, 85SMX style Rakon Ltd LF XTAL016207
1 SP401 PC board speaker, SMD mount Veco Vansonic 20CS08KQ-150ND
1 XC201 16MHz uXtal GSX-323, 2.0 x 2.5 mm SMD
10ppm
Golledge GSX-323/111BF
16.0MHz
1 U401 Citizen 4.2x4.2mm SMD electmic Citizen CHM-04C-03
1 SW301 ALPS 4-directional switch with center push
function
ALPS SKRHABE010
1 PCB101 AVRRAVEN PCB A08-0402
2 J501, J502 LR44 battery clip, SMD Keystone
Corp.
2996TR
1 J503 1x3 pin header, 2 mm pitch, THM SAMTEC TMM-103-01-L-S
1 JS501 Jumper cap for 2.00mm pinheader SAMTEC 2SN-BK-G
2 BT501, BT502 LR44 coin-cell battery
1 D301 LED, Red, SMD 0603 Lumex SML-LX0603SRW-TR
1 U302 AVRRAVEN LCD Orient Display 0710091B

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Appendix C. Atmel AVRRAVEN LCD
Figure 3-4. AVRRAVEN Segments.