Download Kit Instructions - Jameco Electronics

MiniRover V2.0
PART NO. 2209684
The miniRoverV2.0 is an electronic circuit board compound by an 8 bit microcontroller (Atmel Atmega 328) and an H bridge motor
driver (Texas L293D), capable to control two small electric motors, it is a good choice to build small robots, UGV line follower and to
learn about programming and mechatronics.
The goal of this project is:
1- Use of electronic components that can be easy to find and mounting without hard experience in electronic soldering, there are no
SMD components.
2- Only two ports of the microcontroller to change the rotation direction of two small electric motors.
3- One port to control speed of rotation (PWM control).
The digital pins PD4, PD3 of microcontroller Atmega 328, control the rotation direction of motors, and the pin PD6, control the
speed of rotation (PWM control).
Between Atmega 328 , and L293D, has a logical inverter made with two transistors BC548, the function of the this inverter is to
provide the logic levels required to change direction of rotation of motors, in an arrangement in which use a smaller number of ports
of the microcontroller. Without this arrangement, would be necessary four ports of microcontroller to change the sense of rotation for
only one electric motor.
To increase speed, just increase the PWM signal, to stop the motors cut off the PWM signal.
This small code is an example of how to use this board, to program can be used the StudioAvr or Arduino IDE with an Avr
Programmer.
//move two motors one direction//
void setup()
{
pinMode (7 , OUTPUT);
pinMode (8 , OUTPUT);
//pinMode (6, OUTPUT); //PWM control this line is not necessary it is here only for educational purposes//
}
void loop()
{
digitalWrite(7, LOW ); // put PD7low level// digitalWrite(8, LOW); // put PB0 low level
// analogWrite(6, 90); // PWM control analogWrite values from 0 stopped to 255 max
speed
}
Below, the true table to control he motors:
|-------------------------------------------------------------|
LOGICAL INVERTER Q1, Q2
|-------------------------------------------------------------|
PD6 | PB0 | PD7 | MOTOR
|-------------------------------------------------------------|
PWM | 1 |
0 | TURN LEFT
|-------------------------------------------------------------|
PWM | 0 |
1 | TURN RIGHT
|------------------------------------------------------------|
0
|
X |
X | STOP
MOTOR
|-------------------------------------------------------------|
Time Required: 30 minutes depending on experience
Experience Level: Intermediate
Required tools and
parts:
Soldering iron
Screw driver
Studio Avr
AVR Programmer
Bill of Materials:
Qty
Jameco SKU
Component Name
2
308567
Header, 6-Pin
HEADER,VERTICAL,RECEPTACLE 1 ROW,20CONT,.100 INCH (2.54mm),FEMALE HEADER RECEPTACLE
1
743488
Zener diode 3.3v
Diode Zener Single 3.3 Volt 5% 500mW 2-Pin DO-35 Bulk
1
35975
Silicon Rectifier Diode
50 Volt 1 Amp Silicon Rectifier Diode
1
372171
Inductor
10uH Inductive Axial Choke
Features:
Inductance: 10µH
Tolerance: ±5%
Conformal coated axial choke
3
138691
LED
OPTO,LED, 5MM, BLUE DIFFUSED, T1-3/4 468NM, 45 DEGREE, FLANGED
for power ,tx,rx indicator
1
115035
Header, 3-Pin, Dual row
EADER,ST MALE,2RW,6PIN, .1"CTR,.025 PST,.23"GLDTL
for Atmega programmer
3
152347
Connector Terminal Blocks 2 Position
CONNECTOR, .2", TERM BLK (2) VERT .421"L X .351"W X .490"H
For motors and power.
2
254781
Transistor BV548B TO-92 Transistor NPN
RANSISTOR, BC548B, TO-92 TRANS, NPN, SWITCH
For logical inverter.
1
119011
Tactile Switch
Tactile Switch Off Momentary (On) Single Pole Single Throw Round Button PC Pins 0.05 Amp 12 Volt Through Hole
1
2139111
ATmega328P-PU
ATMega328 Microcontroller
Atmel 328 32kB Flash microcontroller
1
526248
Connector DIP 28 pin
SOCKET, IC, 28 PIN, 390261-9, .300", DUAL, LADDER, P/B, TIN
(10) Dip connector for Atmega 328.
1
683121
Connector DIP Socket16
Connector DIP Socket Socket 16 Position 2.54mm Solder Straight Through Hole Tube for L293D.
1
1341966
L293D
The L293D is a quadruple high-current half-H driver. The L293D is designed to provide bidirectional drive currents of up to 600-mA at voltages from 4.5 V to 36 V.
This device is designed to drive inductive loads such as relays, solenoids, dc and bipolar stepping motors, as well as other high-current/high-voltage loads in positivesupply applications.
1
924570
L7805ACV
Standard Regulator 5 Volt 1 Amp 3 Pin 3+ Tab TO-220 Tube
1
325068
CRYSTAL OSCILLATOR,20.000MHZ
CRYSTAL,20.000MHZ,HC49/US,20PF LOW PROFILE
5
151116
0.1 uF 25 Volt 20% Ceramic Disc Capacitor
15405
22pf 50 Volt Ceramic Disc Capacitor
filter capacitor
2
22 pf capacitor for atmega328 oscillator
3
691104
Resistor Carbon Film 10k Ohm 1/4 Watt 5%
2
690865
Resistor Carbon Film 1k Ohm 1/4 Watt 5%
3
690742
Resistor Carbon Film 330 Ohm 1/4 Watt 5%
1
659892
Resistor Carbon Film 22 Ohm 1/2 Watt 5%
Step 1 - Insert screw terminals.
Insert screw terminals.
Step 2 - Insert DIP Sockets
Insert DIP Sockets Solder Tail - 28-Pin 0.3"for Atmega 328 and DIP Sockets Solder Tail - 16-Pin 0.3"for L293D
Step 3 - Insert voltage regulator and transistors
Insert 5V regulator 7805, transistors BC548, zener diode and headers.
Step 4 - Resistors
Insert resistors, oscillator crystal
Step 5 - Capacitors
Add two capacitors of 22pF for Atmega oscillator and filter capacitors, LEDs, inductor and reset button.
Step 6 - How to configure the Atmega 328 to 20MHZ
Download the Avr Studio at site http://www.atmel.com/tools/atmelstudio.aspx.
Step 7 - How to configure the Atmega 328 to 20MHZ.
2- In this link, show how to configure the AVR programmer http://www.pololu.com/docs/0J36/3.b
Step 8 - How to configure the Atmega 328 to 20MHZ
Open studio Atmel go to TOOLS-DEVICE PROGRAMMING.
Step 9 - How to configure the Atmega 328 to 20MHZ
In DEVICE PROGRAMMING choose Atmega328P, TOOL generally is STK500, Avr Studio detect automatically, INTERFACE ISP.
And click APPLY
Step 10 - How to configure the Atmega 328 to 20MHZ
Go to FUSES, a new Atmega 328P comes from factory with 8MHZ internal clock, to change to run with a 20MHZ crystal, it is
necessary change the LOW FUSE from 0xC2 to 0xD7, after this click in PROGRAM, and it is done.
Step 11 - How to use miniRover V2.0 with Arduino IDE
Go to http://www.arduino.cc/en/Main/Software and download the latest Arduino software for your platform.
Step 12 - How to use miniRover V2.0 with Arduino IDE
Add the following to the end of the boards.txt file in the arduino-1.0.1/hardware/arduino directory:
##############################################################
minirover328pgm.name=ROVER v2.0 w/ ATmega328P via Programmer
minirover328pgm.upload.using=avrispv2
minirover328pgm.upload.maximum_size=32768
minirover328pgm.build.mcu=atmega328p
minirover328pgm.build.f_cpu=20000000L
minirover328pgm.build.core=arduino
minirover328pgm.build.variant=standard
##############################################################
Step 13 - How to use miniRover V2.0 with Arduino IDE
With an AVR ISP programmer such as our USB AVR Programmer, add the following to the end of the programmers.txt file in the
arduino-1.0.1/hardware/arduino directory:
avrispv2.name=AVR ISP v2
avrispv2.communication=serial
avrispv2.protocol=avrispv2 this will allow the Arduino IDE
to program with the avrispv2 protocol used by our USB
AVR Programmer.