Astable Timer with PIC 12F629 / 12F675


Posted on Aug 17, 2012

This software functions as a long period astable mutivibrator. The mark and space period can be set from 1 second up to a maximum 65535 seconds (18h12m15s). Using the internal 4Mhz RC oscillator delays with an accuracy of 99% or better can be achieved The code also implements an edge triggered reset and an active low hold function. The reset edge can be configured for rising or falling edge. The hold function is active low and stretches the timed period for as long as the hold input is held low. In addition to this up to 128 mark/space time pairs can be used which are executed sequentially allowing complex pulse trains to be generated.



By connecting the hold input to the Q output, the code can also be made to function as an edge-triggered monostable timer, using the reset input as the trigger. At power on and after an edge triggered reset the outputs enter a mark state with th




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

Phototransistor 555 Timer
Voltage Regulator
DTMF decoder with voice!
Delayed start for mains equipment
simple intercom circuit with
Transistor LED flasher
Reset IC in Microcontroller Application
Jog shuttle function with automatic control circuit



Top