1. Embedded Systems & Robotics Basics
Submitted to : Submitted by:
Mr. Ritesh Saraswat (guide) Sachin kr. Jain
Ms. Seema Sharma (co-guide) Subhash choudhary
Vivek kr. gupta
2. Embedded Systems
A embedded system is a microprocessor
or microcontroller based electronic device
used for specific task.
It is designed to perform operations
which minimize (or even completely
avoid) need of human control.
3.
4. Types of embedded systems
1. Real time embedded system
(a) Soft real time embedded system
(b) Hard real time embedded system
2. Non real time embedded system
5. Applications of embedded system
• Pen drives
• Hard disk
• Mouse
• Calculators, electronics welding machine
• Cell phones
• Security system
• Alarm system
• Digital camera
• Environment monitoring systems
6. Microcontroller
A Microcontroller is a programmable digital processor with
necessary peripherals. Both microcontrollers and
microprocessors are complex sequential digital circuits meant to
carry out job according to the program / instructions. Sometimes
analog input/output interface makes a part of microcontroller
circuit of mixed mode (both analog and digital nature).
Types:
(a) RISC microcontroller
(b) CISC microcontroller
we have used ATmega16 in training
7. Features of Modern Microcontrollers
• Built‐in Monitor Program
• Built‐in Program Memory
• Interrupts
• Analog I/O
• Serial I/O
• Facility to Interface External Memory
• Timers
9. Features of ATMEGA16
• It is a 40 pin Ic
• Advanced RISC Architecture
• 16K Bytes of In‐System Self‐Programmable Flash
• 512 Bytes EEPROM
• 1K Byte Internal SRAM
• 32 Programmable I/O Lines
• In‐System Programming by On‐chip Boot Program
10. Programming
Programmer basically consists of two parts:
• Software (to open .hex file on your computer)
• Hardware (to connect microcontroller
Hardware depends on the communication port you are using on
the computer (Serial, Parallel or USB).
There are 2 good software which support this hardware and can
communicate with micro controller using this circuit. They are,
• Pony Prog
• At‐Prog
14. Code Vision AVR (CVAVR)
Atmel Microcontrollers are very famous as they are
very easy to use. First of all we need an easy IDE
(Integrated Development Environment) for
developing code. We used CVAVR (Code Vision
AVR)
It has limitation of code size.
It works on computers with Windows platform that is
Windows XP & Vista.
25. I/O functions Register
Input Output functions are set by Three Registers for
each PORT.
DDRX ‐‐‐‐> Sets whether a pin is Input or Output of
Port X.
PORTX ‐‐‐> Sets the Output Value of Port X.
PINX ‐‐‐‐‐> Reads the Value of Port X.
28. • Since Timer works independently of CPU it can be
used to measure time accurately.
• As we know a timer is an 8 bit register that keeps on
increasing its value, so one of the basic conditions is
the situation when timer register OVERFLOWS i.e. it
has counted up to its maximum value (255 for 8 BIT
timers) and rolled back to 0. In this situation timer
can issue an interrupt and we must write an Interrupt
Service Routine (ISR) to handle the event.
29. Timers in Atmega16
Atmega 16 has following timers:-
Timer 0 - It is an 8-bit timer and for this pin no. 4
(PB3) is used.
Timer 1 - It is 16 –bit timer, It has two types
OC1A(8-bit) at pin no 19 and
OC1B(8-bit) at pin no 18.
Timer 2 - It is also an 8-bit timer and pin no 21
(OC2) is used for this.
30. Modes of Timers
There are four modes of timers, are as:
Normal mode
CTC mode
Fast PWM mode
Phase correct PWM mode
39. SPI: Serial Peripheral Interface
• Serial Peripheral Interface Bus or SPI bus is a
synchronous serial data link used to communicate
between two or more microcontroller and devices
supporting SPI mode data transfer.
• In this mode, devices communicate in master/slave
mode where the master device initiates the dataframe.
Multiple slave devices are allowed with individual
slave select (chip select) lines.
40. SPI: Serial Peripheral Interface
• SPI communication protocol consists of following
pins:-
– MOSI : Master Out Slave In (Tx for Master and
Rx for Slave)
– MISO : Master In Slave Out (Rx for Master Tx for
Slave)
– SCK : Serial Clock (Clock line)
– SS : Slave Select (To select Slave chip) (if
given 0 device acts as slave)
41. SPI: Serial Peripheral Interface
MOSI:-Channel where the master sends the
data to the slave and the slave receives it.
MISO:-Channel where the slave sends the data
and the master receives it.
42. SPI: Serial Peripheral Interface
SCK:-Clock is send by the master.
SS:-Slave select when the master wants to
send data to a particular slave it makes its SS
pin low, sends the data and then again makes it
high.
43. UART
In the UART protocol, the transmitter and the receiver
do not share a clock signal. That is, a clock signal does
not emanate from one UART transmitter to the other
UART receiver. Due to this reason the protocol is said
to be asynchronous
44. Serial Port of Computer
• Serial Port is used for communication between the uC
and the computer.
• A serial port has 9 pins.
• For laptop, most probably there wont be a serial port.
In such case, we use a USB to serial Converter.
• For transmitting one byte of data, the serial port will
transmit 8 bits as one bit at a time.
45.
46. Serial Port of Computer
• Pin 3 is the Transmit (TX) pin, pin 2 is the Receive
(RX) pin and pin 5 is Ground pin.
• Other pins are used for controlling data
communication in case of a modem.
• For the purpose of data transmission, only the pins 3
and 5 are required.
47. Motors
Device used to convert electrical energy into mechanical
energy is called a motor.
Some Motors used in embedded systems and robotics
are described as below:
i. Stepper motors
ii. Servo motors
iii. Geared DC Motors
48. Motors
We used Gear motors during Training.
• Gear motors are motors with an integrated gearbox.
• Geared motors have a variety of applications. Some
of its uses are as in wheelchairs, stair wheels etc.
51. Sensors
A sensor is a device that measures a physical quantity
and converts it into a signal which can be read by an
observer or by an instrument.
We can use different types of sensor like,
1. Temperature sensor:
We use LM35 IC as
temperature sensor.
52. Sensors
2. Light Dependent Resistor (LDR):
LDR is basically a resistor whose resistance varies
with intensity of light. More intensity less its
resistance (i.e, in black it offers high resistance and
in white it offers less resistance).
53. Sensors
TSOP:
TSOP 1738 Sensor is a digital IR Sensor; It is logic 1
(+5V) when IR below a threshold is falling on it and
logic 0 (0V) when it receives IR above threshold.
It does not respond to any stray IR,
it only responds to IR falling on it
at a pulse rate of 38 KHz.
55. Sensors
IR-Sensor:
In this we use three main components IR-LED, Photo
diode & LM358 IC.
From any “non black body” obstacle IR reflects and
falls on photo diode.
Hence Photo diode become forward bias, and it turn
on the IC LM358 that gives the output.