clk3 binary alarm clock


Posted on Feb 6, 2014

This is the first electronic circuit I designed from scratch, my first time programming a MCU, the first time I wrote an application in assembly language and my second homemade PCB. Usually people starts building very simple things and they increase the complexity of their work a bit at a time, but I prefer to learn and build things much more comp


clk3 binary alarm clock
Click here to download the full size of the above Circuit.

lex than I am (theoreticaly) capable of, so I learn and work much more faster. Input 7-35V is converted to 5V using a LM7805. The MCU can be programmed by ICSP plugging the programming cable to P2 and activating positions 6 and 7 of S5 and deactivating the rest of them. For using the circuit in clock-mode (not programming-mode) positions 1-5 of S5 must be activated and 6-7 deactivated. LEDs used to show the hours are connected to PORTA, those used to show minutes to PORTC and for seconds to PORTD. Button S1 rises the time one hour, S2 one minute, S3 sets up the actual time and S4 the alarm time. The diode D21 seems to be upside down but it isn`t because P1 is the power jack, so current must flow from the GND of the circuit to P1-1 which is the ground of the external power. The circuit has two ground lines: GND and Vss. Usually (clock-mode) they are shorted but they are split when the PIC is being programmed so Vss (ground of the ICSP programmer) is completely isolated from the rest of the circuit.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

DC servo motor driver with MC33030
miniature audio amplifier
Conversion Receiver For 160 To 20M Circuit
10 Note Sound Synthesizer Circuit
DC Motor Control
ta8122 am fm radio receiver electronic project circuit design
Easy 24C I2C Serial EEPROM Interfacing with AVR Microcontrollers
fet low distortion crystal oscillator
FET based audio preamplifier
Voice modulator circuit
Sony Triniton TV
2 transistor buffer



Top