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sacalu
Joined: 10 May 2007 Posts: 4
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help pls..clock/timer0 |
Posted: Thu Jun 07, 2007 4:34 am |
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I have a pic16f88 with a 20MHz crystal,and i need a clock speed of 200KHz
with timer0 at 400MHz...Is this posible and if so...can you pls post a code for it?...
is timer0 set acording to the 20MHz crystal or acording to the clock?
This might be a newbish question...thar's because...i'm newbie |
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Ttelmah Guest
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Posted: Thu Jun 07, 2007 5:14 am |
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Er. 400MHz... No.
Table 18-6 in the data sheet. Minimum clock input period. 60nSec (asynch). Hence fastest clock possible, is 16.66MHz for the timer input in this mode. Running synchronously instead, with your Tcy of 50nSec, you get (Tcy+40)/8 nSec minimum, which gives 11.25nSec (as the absolutely fastest clock acceptable), 88.8MHz, but the counter then only runs at 11.1MHz.
There is no way, any normal PIC, can do anything at 400Mhz...
Best Wishes |
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sacalu
Joined: 10 May 2007 Posts: 4
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Posted: Thu Jun 07, 2007 7:04 am |
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sry...i made a mistake in my post...i ment 400KHZ |
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