mikroElektronika EasyAVR4 User manual

SOFTWARE AND HARDWARE SOLUTIONS FOR THE EMBEDDED WORLD
MikroElektronika
Development tools - Books - Compilers
Software and Hardware
solutions for Embedded World
EasyAVR4
User’s Manual
With useful implemented peripherals, plentiful practical
code examples and a broad set of additional add-on
boards (Serial Ethernet, Compact Flash, MMC/SD,
ADC, DAC, CAN, RTC, RS-485, etc.), MikroElektronika
development boards make fast and reliable tools that
can satisfy the needs of experienced engineers and
beginners alike.
2in 1
ATMEL
DEVELOPMENT
BOARD
AVR
DEVELOPMENT
BOARD
AVR
ATMEL
USB 2.0
IN-CIRCUIT
PROGRAMMER
USB 2.0
IN-CIRCUIT
PROGRAMMER

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No part of this manual, including the product and software described in it, may be repro-
duced, transmitted, transcribed, stored in a retrieval system, or translated into any language
in any form or by any means, except documentation kept buy the purchaser for backup pur-
poses, without the express written permission of MikroElektronika company.
Product warranty or service will not be extended if the product is repaired, modified or
altered, unless such repair, modification or alteration is authorized in writing by
MikroElektronika.
MIKROELEKTRONIKA PROVIDE THIS MANUAL “AS IS” WITHOUT WARRANTY OF ANY
KIND, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED
WARRANTIES OR CONDITIONS OF MERCHANTABILITY OR FITNESS FOR A PARTIC-
ULAR PUROSE.
IN NO EVENT SHALL MIKROELEKTRONIKA, ITS DIRECTORS, OFFICERS, EMPLOY-
EES OR DISTRIBUTORS BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR
CONSEQUENTIAL DAMAGES(INCLUDING DAMAGES FOR LOSS OF PROFITS, LOSS
OF BUSINESS, LOSS OF USE OR DATA, INTERRUPTION OF BUSINESS AND THE
LIKE) EVEN IF MIKROELEKTRONIKA HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGES ARISING FROM ANY DEFECT OR ERROR IN THIS MANUAL OR
PRODUCT.
SPECIFICATION AND INFORMATION CONTAINED IN THIS MANUAL ARE FURNISHED
FOR INTERNATIONAL USE ONLY, AND ARE SUBJECT TO CHANGE AT ANY TIME WITH-
OUT NOTICE, AND SHOULD BE CONSTRUED AS A COMMITMENT BY
MIKROELEKTRONIKA
MikroElektronika assumes no responsibility or liability for any errors or inaccuracies that
may appear in this manual, including the product and software described in it.
Product and corporate names appearing in this manual may or may not be registered trade-
marks or copyrights of their respective companies, and are used only for identification or
explanation and to the owners benefit, without intent to infringe.
Second edition
December 2006

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CCOONNTTEENNTTSS
CONNECTING THE SYSTEM page 4
INTRODUCTION page 5
Power Supply page 10
On-board USB 2.0 programmer page 11
Jumpers page 7
Switches page 6
MCU sockets page 8
LEDs page 14
Pushbutton switches page 16
MMC/SD (Multimedia Card) page 32
7-segment displays page 19
Graphic LCD page 20
LCD 2x16 in 4-bit mode page 21
LCD 2x16 in 8-bit mode page 22
4.096V voltage regulator page 27
CONTENTS
DESCRIPTION OF THE DEVELOPMENT SYSTEM page 5
JTAG connector page 31
Direct Port Access page 29
RS-232 Communication page 24
DS1820 Digital Thermometer page 26
Oscillator page 12

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CCOONNNNEECCTTIINNGGTTHHEESSYYSSTTEEMM
CONNECTING THE SYSTEM
Step no.1
Step no.2
Step no.3
Step no.4
The development system box contains the development system, product CD, USB cable,
RS232 cable and this manual.
The first thing to do is to take the system out of the box. Unpack the USB cable and con-
nect it to the PC. Please use USB ports on the back of the PC with direct connection to the
motherboard.
Install the AVRprog programmer and drivers. Start the installation from the product CD:
CD_Drive:\product\zip\AVRprog_setup.exe.
After the installation connect the USB cable to the EasyAVR4 board. You will be asked for
the AVRprog drivers. Point to them in order to finish the driver installation. They are placed
in the folder:
System_Drive:\Program Files\Mikroelektronika\AVRFLASH\Driver.NT
Run and use AVRprog as explained in the document ‘AVRprog programmer’.
CD_Drive:\product\pdf\avrprog_manual.pdf.
After these 4 steps, your EasyAVR4 is installed and ready for use. You can try to read a pro-
gram from the chip or to load an example from the examples folder of mikroElektronika’s
compilers for AVR or from the product CD:
CD_Drive:\product\zip\easyavr4_examples.zip.

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IINNTTRROODDUUCCTTIIOONN
The EasyAVR4 development system is a full-featured development board for Atmel AVR
microcontrollers. It has been designed to allow students and engineers to easily exercise and
explore the capabilities of AVR microcontrollers. It allows AVR microcontrollers to be inter-
faced with external circuits and a broad range of peripheral devices, allowing a user to con-
centrate on software development.
Figure 1 illustrates the development board. Each component is marked on a silkscreen, both
top and bottom. These marks describe connections to the microcontroller, operation modes,
and provide some useful notes. The need for additional schematics is minimized since all
relevant information is printed on the board.
INTRODUCTION
Figure 1. EasyAVR4 development board
ATMEL
DEVELOPMENT
BOARD
AVR
DEVELOPMENT
BOARD
AVR
ATMEL

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SSWWIITTCCHHEESS
SWITCHES
The EasyAVR4 development board features a number of peripherial devices. In order to
enable these devices before programming, you need to check if appropriate jumpers or
switches have been properly set. Switches are devices that have two positions - ON and
OFF, which have a role to establish or break a connection between two contacts. The
EasyAVR4 development board has three groups of switches.
The first group, SW1, enables connections between the microcontroller port with analog
capabilities (PORTA) and external pull-up/down resistors. The pull-up/down resistors
should be disconnected from the analog input pins, otherwise they will affect the input volt-
age level. When PORTA pins are used as digital inputs/outputs, the appropriate pull-
up/down resistors should be enabled.
The second group, SW2, is used to enable LEDs connected to PORTA, PORTB, PORTC
and PORTD. For example, if the switch for PORTB is OFF, all PORTB LEDs will be turned
off.
The upper four switches of SW3 are used to enable SPI communication for interfacing with
MMC card. The lower four switches of SW3 are used to enable the 7-segment displays. If
you don’t need the 7-segment displays in your project, these switches should be OFF.
Switch is ON
Switch is OFF
1
ON
432 5876
Figure 2.
Group of 8 switches
Switch 1 is ON, and other
switches are OFF

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JJUUMMPPEERRSS
JUMPERS
Jumpers, like switches, can break or establish a connection between two points. Beneath the
plastic cover of the jumper is a metal contact, which makes a connection if the jumper is
placed between two disconnected pins.
For example, the RS232 communication has two jumpers, J11 and J12, used as switches.
They are used to connect or disconnect Rx pin to PD0 and Tx pin to PD1 pin of the micro-
controller. A connection is made when the jumpers are placed between two contacts.
More often jumpers are used as a selector between two possible connections by using a three
pin connector. As illustrated in Fig. 4, the middle contact can be connected to the left or right
pin, depending on the jumper’s position.
Left line
is selected
All lines are
disconnected
Right line
is selected
Jumper is ON
Jumper is OFF
Figure 3.
Figure 4.
Jumper as a switch
Jumper as a
multiplexer

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MMCCUUSSOOCCKKEETTSS
MCU SOCKETS
EasyAVR4 is delivered with a ATmega16 40-pin microcontroller. Users can remove this one
and fit a different microcontroller in DIP40, DIP28, DIP20, DIP18, DIP14 or DIP8 packages
of an adequate pinout.
Note: Since all packages have parallel connections, there must not be more than one micro-
controller on the board at a time.
Figure 5. MCU sockets
Note: Jumper J13 should be enabled only if you want to use DIP8 microcontroller with
external clock source.
Note: There are two DIP40 sockets, with different pinouts (SKT1 and SKT2). When put-
ting 40-pin microcontoller into DIP40 socket choose the one with corresponding pinout. For
example, ATmega8535 uses SKT2 socket, while ATmega8515 uses SKT1 socket.

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MMCCUUSSOOCCKKEETTSS
DIP40
PB1
PB2
PB3
PB4
PB5
PB6
PB7
RST
VCC
PC7
AVCC
PA7
PA6
PA5
PA4
PA3
PA2
PA0
PA1
GND
XT2
PB0
AREF
AGND
PB5
PB5
PORTB
DIP28 PB5
DIP20
1 ON
432
PORTB
J6
SW2
PB5
J2
PB5
VCC
PORTB
CN2
VCC
VCC
Microcontroller’s pins are routed to various peripherals as illustrated in Fig. 6. All ports have
direct connections to Direct Port Access connectors. Such connectors are typically used for
connecting external peripherals to the board or for providing useful points for connecting
digital logic probe.
All ports are connected to LEDs, push-button switches and pull-up/down resistors, which
allow easy monitoring and testing of digital pin state .
Some pins are connected to other peripherials such as the DS1820 temperature sensor, RS-
232 communication, 7-segment displays, LCD, etc.
System connection
Figure 6.

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PPOOWWEERRSSUUPPPPLLYY
As a power supply source, users can select either a regulated supply from the USB cable
(default) or an external power supply. In case of the USB power supply, the system should
be connected to a PC using the USB programming cable, while the jumper J10 should be
set in the right-hand position.
In the case of an external power supply, the EasyAVR4 board produces +5V using an
LM7805 voltage regulator. The external power supply can be AC or DC, with a voltage
between 8V and 16V and the jumper J10 should be set in the left-hand position. In Fig. 7
you can see USB and external power supply connectors.
GND
Vin Vout
VCC
CN7 8-16V (AC/DC)
+
E1
470uF
C2
100nF
E3
470uF
C9
100nF
1
2
VCC
D-
D+
GND
5V 5V
USB
FP1
1
2
3
USB yPower Suppl
External Power Supply
EXT
EXT
USB
USB
REG1
7805
J14
C1
100nF
POWER SUPPLY
J10 in the left-hand
position: system will
take power from the
external AC/DC
power adapter.
J10 in the right-hand
position: system will
take power from the
USB cable.
USB and power supply connectors
Figure 7.
Figure 8. Power supply select jumper
Figure 9. J10 is set to USB power supply
EXT USB
USB
connector
USB
connector
External power
supply connector
POWER SUPPLY
SELECTABLE
POWER SUPPLY
SELECTABLE

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OONN--BBOOAARRDDUUSSBBPPRROOGGRRAAMMMMEERR
ON-BOARD USB 2.0 PROGRAMMER
There is no need for the use of external
equipment during programming, as the
EasyAVR4 development system has its
own on-board USB 2.0 programmer.
All you need to do is connect the system
to a PC using the USB cable. Then, load
your program into the microcontroller
via the AVRprog programming software,
which is supplied with the board.
VCC
USB LINK
27
SWITCH
TO PERIPHERALS
ON DEVELOPMENT BOARD
AVRprog
On-Board USB
programmer
VCC
D-
D+
GND
USB
CN8
1
2
3
4
USB CONN.
VCC
27
1K
POWER
1K
10K
Reset
100n
VCC
VCC
ATMEGAxxxx
PB1
PB2
PB3
PB4
PD1
PD2
PB5
PB6
PB7
PD4
PD5
PD6
PC1
PC0
PD7
PC2
PC3
PC4
PC5
PC6
PC7
PA7
PA6
PA5
PA4
PA3
PA2
PA0
PA1
PD3
PB0
PD0
RST
VCC
GND
XT2
XT1
AREF
AGND
AVCC
VCC
OSCILLATOR
Figure 10. On-Board USB programmer
Figure 11. Switch schematic
Note: There is no need for manually reseting MCU after programming. The programmer
will reset the MCU automatically.
USB 2.0
IN-CIRCUIT
PROGRAMMER
USB 2.0
IN-CIRCUIT
PROGRAMMER

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OOSSCCIILLLLAATTOORR
OSCILLATOR
EasyAVR4 development board has on-board oscillator circuit for generating microcon-
troller’s clock input. Within the AVRprog programmer you can either choose internal RC
oscillator or external clock. External oscillator is connected to the XT1 pin of the microcon-
troller. Microcontroller in DIP8 package doesn’t have pin that is dedicated only for the
oscillator clock input. Because of the small pin count, it has PB4 pin multiplexed between
I/O and clock input function.
Figure 12.
Oscillator
Note: Jumper J13 should be enabled only if you want to use DIP8 microcontroller with
external clock source.
If you want to use pin PB4 with I/O function you should use internal RC oscillator. If you
don’t need I/O function of the PB4 pin, then you can use on-board oscillator by enabling
jumper J13. By doing this, you are making a direct connection between the oscillator circuit
and PB4 pin.

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OOSSCCIILLLLAATTOORR
ATMEGAxxxx
PB1
PB2
PB3
PB4
PD1
PD2
PB5
PB6
PB7
PD4
PD5
PD6
PC1
PC0
PD7
PC2
PC3
PC4
PC5
PC6
PC7
PA7
PA6
PA5
PA4
PA3
PA2
PA0
PA1
PD3
PB0
PD0
RST
VCC
GND
XT2
XT1
AREF
AGND
AVCC
VCC
OSCILLATOR
10K
Reset
100n
VCC
GND
VCC
A
B
C
D
E
F
C12
22pF
C11
22pF
74HC04
X2
8MHz
R8
1K
R7 1M
PB4
J13
VCC
Figure 13. Oscillator connection with MCU
Note: In order to simplify the schematics in this man-
ual, the oscillator circuit is represented by this symbol.
OSCILLATOR

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LLEEDDss
Light Emitting Diodes (LEDs) are the most commonly used components, usually for dis-
playing pin’s digital state. EasyAVR4 has 32 LEDs that are connected to the microcon-
troller’s PORTA, PORTB, PORTC and PORTD.
LEDs
Figure 14. Light Emitting Diodes
Each group of eight LEDs can be enabled or disabled using the switch SW2. Fig. 15. illus-
trates the connection of a LEDs to PORTA of the microcontroller. A resistor is used in series
with the LED to limit the LED's current. In this case the resistor's value is 1K.

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The LEDs are enabled when the corresponding switch on SW2 is on. When enabled, LEDs
will display the state of the corresponding microcontroller pin; otherwise the LEDs will
always be off, no matter what the port state is, as no current can flow through LED.
RN6
R-SIL 8/9
1
2
3
4
5
6
7
8
9
PA0
PA1
PA2
PA3
PA4
PA5
PA6
PA7
1 ON
432
PORTD LED
PORTC LED
PORTB LED
PORTA LED
CURRENT FLOW
ATMEGAxxxx
PB1
PB2
PB3
PB4
PD1
PD2
PB5
PB6
PB7
PD4
PD5
PD6
PC1
PC0
PD7
PC2
PC3
PC4
PC5
PC6
PC7
PA7
PA6
PA5
PA4
PA3
PA2
PA0
PA1
PD3
PB0
PD0
RST
VCC
GND
XT2
XT1
AREF
AGND
AVCC
VCC
OSCILLATOR
10K
Reset
100n
VCC
10K
Figure 15.
LED schematic

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PPUUSSHHBBUUTTTTOONNSSWWIITTCCHHEESS
ATMEGAxxxx
PB1
PB2
PB3
PB4
PD1
PD2
PB5
PB6
PB7
PD4
PD5
PD6
PC1
PC0
PD7
PC2
PC3
PC4
PC5
PC6
PC7
PA7
PA6
PA5
PA4
PA3
PA2
PA0
PA1
PD3
PB0
PD0
RST
VCC
GND
XT2
XT1
AREF
AGND
AVCC
VCC
OSCILLATOR
10K
Reset
100n
VCC
AVRprog
On-Board USB
programmer
EasyAVR4 has 32 push buttons, which can be used
to change states of digital inputs to microcontroller's
ports. There is also one switch that acts as a RESET.
Reset switch schematic is shown in Figure 17.
PUSHBUTTON SWITCHES
Figure 18.
Pushbutton switches
Figure 16. Reset switch
Figure 17.
Reset switch schematic

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PPUUSSHHBBUUTTTTOONNSSWWIITTCCHHEESS
VCC
RA0
RA1
RA2
RA3
RA4
RA5
RA6
RA7
RB0
RB1
RB2
RB3
RB4
RB5
RB6
RB7
RC0
RC1
RC2
RC3
RC4
RC5
RC6
RC7
RD0
RD1
RD2
RD3
RD4
RD5
RD6
RD7
PORTA PORTB PORTC PORTD
0V while button
is pressed
+5V while button
is pressed
J6
ATMEGAxxxx
PB1
PB2
PB3
PB4
PD1
PD2
PB5
PB6
PB7
PD4
PD5
PD6
PC1
PC0
PD7
PC2
PC3
PC4
PC5
PC6
PC7
PA7
PA6
PA5
PA4
PA3
PA2
PA0
PA1
PD3
PB0
PD0
RST
VCC
GND
XT2
XT1
AREF
AGND
AVCC
VCC
OSCILLATOR
10K
Reset
100n
VCC
Figure 19.
Buttons schematic
Buttons connections to PORTA, PORTB, PORTC and PORTD are shown in Fig. 19. Jumper
J6 determines whether a button press will bring logical zero or logical one to the appropri-
ate pin.
When button is not pressed, pin state is determined by the pull-up or pull-down port
jumpers.
In the example shown in Fig. 19, J6 is connected to +5V, therefore pressing the buttons will
bring logical one to the appropriate pins.

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PPUUSSHHBBPPUUSSHHBBUUTTTTOONNSSWWIITTCCHHEESS
On Fig. 20 the J1 jumper is set
to pull-up, therefore when the
button is not pressed, pull-up
resistor pulls the microcon-
troller’s PA3 pin to +5V.
A button press causes the port
pin to be connected to ground
(J6 is in the lower position).
Thus, only when the button is
pressed the microcontroller
will sense a logical zero; other-
wise the pin state will always
be logical one.
On Fig. 21 the J6 jumper is set
to pull-down, therefore when
the button is not pressed, pull-
down resistor pulls the micro-
controller’s PA3 pin to 0V.
A button press causes the port
pin to be connected to +5V (J6
is in the higher position).
Thus, only when the button is
pressed the microcontroller
will sense a logical one; other-
wise the pin state will always
be logical zero.
ATMEGA
PB1
PB2
PB3
PB4
PB5
PB6
PB7
RST
VCC
PC7
AVCC
PA7
PA6
PA5
PA4
PA3
PA2
PA0
PA1
GND
XT2
PB0
AREF
AGND
PA3
PORTA pull-up
0V while pressed
vcc
J1
1
ON
8765432
SW1
vcc
J6
VCC
ATMEGA
PB1
PB2
PB3
PB4
PB5
PB6
PB7
RST
VCC
PC7
AVCC
PA7
PA6
PA5
PA4
PA3
PA2
PA0
PA1
GND
XT2
PB0
AREF
AGND
PA3
PORTA pull-down
5V while pressed
vcc
vcc
J1
1
ON
8765432
SW1
J6
VCC
Figure 20.
Figure 21.
Button with pull-up resistor
Button with pull-down resistor

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7-SEGMENT DISPLAYS
EasyAVR4 has four 7-segment displays in multiplex mode. Data lines are connected to
PORTA, while each display is enabled through the lower four bits of PORTB.
dp
R28
10K
Q1
e
d
c
dp
b
a
f
g
Q4
Q3
Q2
10K 10K 10K
R29 R30 R31
8.
8.
a
b
c
d
e
f
g
PB7 SCK
PB6
MISO
PB5 MOSI
PB4 MMC-CS
DIS3
DIS3 DIS2 DIS1 DIS0
PB3
DIS2
PB2
DIS1
PB1
DIS0
PB0
1 ON
8765432
SW3
R2-R9
8.
8.
123
45
10 9 8 76
8.
8.
123
45
10 98
76
8.
8.
123
45
10 9 8 76
8.
8.
123
45
10 98
76
ATMEGAxxxx
PB1
PB2
PB3
PB4
PD1
PD2
PB5
PB6
PB7
PD4
PD5
PD6
PC1
PC0
PD7
PC2
PC3
PC4
PC5
PC6
PC7
PA7
PA6
PA5
PA4
PA3
PA2
PA0
PA1
PD3
PB0
PD0
RST
VCC
GND
XT2
XT1
AREF
AGND
AVCC
VCC
OSCILLATOR
10K
Reset
100n
VCC
Figure 22.
7-segment displays
Figure 23. 7-segment displays schematic
8.
8.
8.
8.
7
S
E
G
7
S
E
G
R
E
A
D
Y
R
E
A
D
Y

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GGRRAAPPHHIICCLLCCDD112288XX6644
In order to enable GLCD,
jumper J8 should be set to
the upper position, labeled
as GRAPH.
GRAPHIC LCD
A graphic LCD (GLCD) allows advanced visual messages to be displayed. While a charac-
ter LCD can display only alphanumeric characters, a GLCD can be used to display mes-
sages in the form of drawings and bitmaps. The most commonly used graphic LCD has the
screen resolution of 128x64 pixels. Before a GLCD is connected, the user needs to set the
jumper J8 (Fig. 24) to the upper position. The GLCD’s contrast can be adjusted using the
potentiometer P1, which is placed to the right of the GLCD.
ATMEGAxxxx
PB1
PB2
PB3
PB4
PD1
PD2
PB5
PB6
PB7
PD4
PD5
PD6
PC1
PC0
PD7
PC2
PC3
PC4
PC5
PC6
PC7
PA7
PA6
PA5
PA4
PA3
PA2
PA0
PA1
PD3
PB0
PD0
RST
VCC
GND
XT2
XT1
AREF
AGND
AVCC
VCC
OSCILLATOR
10K
Reset
100n
VCC
P1 10K
Vee
Vo
Contrast
Adjustment
J8
GRAPH.
CHAR.
R/W
E
D7
D6
D5
D4
D3
D2
VCC
VCC
D5
D4
D3
D2
D1
D0
E
R/W
RS
LED-
Vo
LED+
VCC
Vee
GND
RST
CS2
D7
CS1
D6
120
LCD8 contrast
selected
GLCD and LCD8
contrast not selected
GLCD contrast
selected
R19 10
VCC
CS1
CS2
RS
D1
D0
RST
PA5
PA4
PA3
PA2
PA1
PA0
PD6
PD5
PD4
PD7
PD3
PA7
PD2
PA6
Figure 26.
GLCD schematic
Figure 24.
Figure 25.
GLCD selection jumper
GLCD
GRAPHIC LCD
CONNECTOR
ON-BOARD
GRAPHIC LCD
CONNECTOR
ON-BOARD