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???
02/18/08 21:05
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#151055 - I wonder
Responding to: ???'s previous message
Locking one's timing to a specific baud-rate generator crystal can prove a serious disadvantage under some circumstances, e.g. this case. It is not unsolvable with the "old, tried-and-true" crystal but if it's convenient, why not try, say, 24 MHz? You can get "close enough" to low standard baud rates with that.
using T1 you can go no higher than 4800 (and T2 is soooo useful for other stuff) of course, if you can spare T2 you can get to 28k, but that I will even consider 'low'

Aside from that, dividing 11059200 by 49152 in a 16-bit counter leaves a divide-by-225 to generate 1 second.
I wonder how you are going to fit 11059200 in 16 bits :)

Anyhow, i wonder what 'lack of precision' any decent crystal frequency will give at 1-30 seconds.

Yes, Richard a 'baudrate crystal' is not always the right choice, but most often it is.

As an example using USB I am forced to clock at 12MHz, and I have to multiply that up to 48MHz (the chip has a PLL) to get a decent T2 baudrate.

Erik

List of 10 messages in thread
TopicAuthorDate
11.059Mhz clock to create 1-30 second delay in C?            01/01/70 00:00      
   as far as I remember...            01/01/70 00:00      
      It's worse than that, Jim            01/01/70 00:00      
   solution?            01/01/70 00:00      
   Not nested loops!            01/01/70 00:00      
      I'll check those out tonight after work            01/01/70 00:00      
         delay needs to be centered around 5 seconds or so            01/01/70 00:00      
            Samuel Clemens said            01/01/70 00:00      
               Couldn\'t use of a different crystal solve this?            01/01/70 00:00      
                  I wonder            01/01/70 00:00      

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