MJEmbesys Technocrats

DC MOTOR INTERFACING WITH ARM (LPC2148) CONTROLLER Motors (Actuators) are important components of embedded systems. Whether it may be a simple DC Motor, or accuracy based Servo Motor, or a precision based Stepper motor, all types of motors are often used in many embedded systems and micro-controller based projects. When talking about simple DC Motors in Micro-controller based system, there are only three tasks we can do: rotate the motor in forward direction, rotate the motor in reverse direction and control the speed of rotation. In here, we will interface a simple DC Motor with ARM7 based Micro-controller i.e. LPC2148. Here, we will simply change the direction of the rotation of the motor using a Motor Driver IC (L293D). For controlling the speed of rotation of the DC Motor, we will see another project as it involves ADC and PWM concepts. The aim of this project is to control a simple DC Motor with ARM7 LPC2148 with the help of L293D (Motor driver) IC. Circuit Diagram ...

Interrupts: The interrupts refer to a notification, communicated to the controller, by a hardware device or software, on receipt of which controller momentarily stops and responds to the interrupt. Whenever an interrupt occurs the controller completes the execution of the current instruction and starts the execution of an  Interrupt Service Routine  (ISR) or Interrupt Handler.  ISR  is a piece of code that tells the processor or controller what to do when the interrupt occurs. After the execution of ISR, controller returns back to the instruction it has jumped from (before the interrupt was received).  The interrupts can be either  hardware interrupts  or  software interrupts .   Interrupt Sources:             Original 8051 has 6 sources of interrupts ·        Reset ·        Timer 0 overflow ·  ...

What is Crystal Oscillator Circuit and its Working? An  electronic circuit  or electronic device that is used to generate periodically oscillating electronic signal is called as an electronic oscillator. The electronic signal produced by an oscillator is typically a sine wave or square wave. An electronic oscillator converts the direct current signal into an alternating current signal. The radio and television transmitters are broad casted using the signals generated by oscillators. The electronic beep sounds and video game sounds are generated by the oscillator signals. These oscillators generate signals using the principle of oscillation. There are different types of oscillator electronic circuits such as Linear oscillators – Hartley oscillator, Phase-shift oscillator, Armstrong oscillator, Clapp oscillator,  Colpitts oscillator , and so on, Relaxation oscillators – Royer oscillator, Ring oscillator, Multivibrator, and so on, and Voltage Controlled Oscillator (VC...

RTC-DS1307 Interfacing with 8051 The Real-time clock DS1307 IC basically is stand-alone time clock with following features. ·          Real-time clock (RTC) counts seconds, minutes, hours, date of the month, month, the day of the week, and year with leap-year compensation valid up to 2100. ·          The clock operates in either the 24-hour or 12-hour format with AM/PM indicator. ·          56-byte, battery-backed, non-volatile (NV) RAM for data storage ·          Two-wire(I2C) serial interface ·          Programmable squarewave output signal ·          Automatic power-fail detect and switch circuitry ·          Consumes less than 500nA in battery backup mode with oscillator running ·  ...