Blog Archives
Posted on 25 Jun 2008
This is DC motor speed control based on PIC16F867.The circuits use frequency PWM about 10KHz which does not make a noise in the motor.This project can drive 1 Amp motor current without heat.The motor speed controled by potentiometer which is connected to ADC input.[more]
Posted on 24 Jun 2008
This is a nice analog clock based on PIC16F84.The meter control by pulse width modulation (PWM). It consists of three analog meters with scales that went from 1-12, 0-59, and 0-59 and indicated hours, minutes, and seconds respectively.[more]
Posted on 13 Mar 2008
This is an improved version of Mitch Altman’s Brain Machine.The hardware is based on an ATMega8.It uses only very few of the I/O ports: two for audio, two for LEDs, one for a pushbutton, so it should be easy to use another controller that has an 8bit timer with two PWM channels (OCxA, OCxB).Add a piece of prototyping PCB, four capacitors, two resistors, a switch, connectors for headphones and glasses, and two AA cells, and you’re done.[more]
Posted on 13 Feb 2008
This is a simple, programmable, autonomous and extensible LED matrix with the possibility of being controlled by a computer using a RS232 connection. Its basic modules are the Controller Board, the I/O Port expander boards and the LED matrix cardboard support. The micro controller is a common Microchip PIC16F88, which has built-in support for I2C slave with a minimal support for I2C master, ASUART, PWM,multiplexed ADC and other interesting peripherals.The controller board also has an external 512kbit EEPROM to allow a bigger storage of drawing patterns and it uses the common MAX232 level shifter for easy interface with the PC RS232.The I/O port expander boards, which control both the vertical and horizontal lines of the matrix, were built around the MCP23016, which has 16 I/O lines and built-in I2C slave.[more]
Posted on 04 Feb 2008
This is the circuit which inputs the control voltage which was created by the turning of the motor in PIC. The input voltage to PIC is converted by A/D converter. Changed voltage is used for the PWM function of the CCP to control the motor drive. At the circuit this time, a small motor is used as the generator to detect the number of rotations of the motor. The input voltage (the control voltage) to PIC is changed by the fluctuation of the number of rotations of the motor. [more]
