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Author Topic: PIC 16f877 clock frequency...  (Read 4061 times)

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Offline sambhavTopic starter

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PIC 16f877 clock frequency...
« on: February 23, 2007, 12:01:16 PM »
hi...

i have designed my project using pic 16f877 microcontroller.
the program includes some delay loops which r written taking into consideration a 4Mhz crystal. V hv used a 4Mhz crystal.
but the problem is dat v found the following PIC.
On the chip its written

PIC 16F877 - 20/P 301

frm da datasheet i learnt dat 20 refers to the frequency range..!!
Now what does FREQ RANGE mean... is it the frequency on which da PIC works or is it da MAX frequency on which it works.. or sumthing else..??
In dat case can i use 4Mhz crystal with da same.. will it work.. or i'll hv 2 use a 20Mhz crystal..?? in case of 20Mhz can anyone provide me da required interconnections for da operation of da PIC..??
plz answer my question..

Thank you..
Sambhav

Offline JonHylands

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Re: PIC 16f877 clock frequency...
« Reply #1 on: February 23, 2007, 01:28:33 PM »
the 20 signifies that you can clock the PIC at anything up to 20 MHz.

You can run your PIC at 4 MHz with no worries.

- Jon

Offline sambhavTopic starter

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Re: PIC 16f877 clock frequency...
« Reply #2 on: February 24, 2007, 12:15:24 AM »
Thanx a lot..

Offline Eco19R

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Re: PIC 16f877 clock frequency...
« Reply #3 on: March 03, 2007, 03:23:16 AM »
up to and at 20 MHZ, just wanted to add that-  :D

Oh and don't forget to put the 18-22 pf caps from each crystal side to ground -
« Last Edit: March 03, 2007, 03:25:53 AM by Eco19R »

 


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