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PIC16f877a internal Oscillator...

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kgavionics

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hi
i read in this here and in microchip forum that many users says that pic16f877a does'nt have an internal oscillator?are you sure about that? please take a look to my video



https://www.youtube.com/watch?v=TDd_Rh2qb10

i removed the crystal and the capacitors and i have the circuit working as you can see in the video

can you comment guys what's going on?
 

Hi
Ground the pin 13 and 14 of PIC16f877a then check

You can have internal oscillate with PIC16f887a
 
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i removed the crystal and the capacitors and i have the circuit working as you can see in the video

can you comment guys what's going on?

Hi,

Most pics can be clocked by a simple RC network, if those pins are left unconnected the circuitry will probably just oscillate on its own so you get random timings.

Thats why any unused pin should be made as outputs, or if specified as an input, pulled up or down with a resistor to avoid such problems
 
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    PA3040

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Hi,

Most pics can be clocked by a simple RC network, if those pins are left unconnected the circuitry will probably just oscillate on its own so you get random timings.

Thats why any unused pin should be made as outputs, or if specified as an input, pulled up or down with a resistor to avoid such problems

Yes you're right :-D as my teacher always repeat:dont leave any floating pin what ever the reason.thx for the trick
 
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