Oscillator Controller for 8bit PIC Microcontrollers

This is oscillator controller for 8bit PIC microcontrollers which is specifically design to debug MCUs and related circuits by without using ICD unit.

This unit consists with low speed oscillator and cycle counter with automatic hold. In current version, oscillator is capable to run in 2 frequency modes and it can count up to 4096 cycles in each run. The number of frequency modes can be extend by adding more capacitors and the upper limit of cycle counter can be increase by adding more 12bit counters (and related circuitries) to the system.

Oscillator waveform in low frequency mode

In current version oscillator can be run in either 66 Hz ~ 70 Hz or 666 Hz ~ 670 Hz (aprox.). This frequency can be adjusted by changing the value of C1 or C2 capacitors (e.g: 0.1MFD can generate 6.39 kHz output signal) OR by replacing R1 with some suitable variable resistor.

In project package we include sample PIC16F84A based project to test with this system. The recommended test attachment is illustrated in below:

Recommended test attachment for PIC16F84A test code

This is open source hardware project and it is licensed under Creative Commons Attribution 4.0 International License. The complete project package is available to download at google drive.

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