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Lpc2000

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Message

Re: LPC214x crystal frequencies // ISP max baudrate 38.4 kBaud using 12 MHz

2005-11-17 by seangra

Based on my calculations, 16MHz can only get to 19,200 (7% error at 
38,400) and 24MHz can get 38,400.  If you went up to 48MHz crystal 
you could get 57,600.

-- Sean

--- In lpc2000@yahoogroups.com, "philips_apps" <philips_apps@y...> 
wrote:
>
> All,
> 
> based on the algorithm the bootloader uses to determine the 
> baudrate, as Joel already found out, it is correct that the max 
> baudrate for 12 MHz is 38400 Baud. 
> 
> Will do some additional tests to determine the baudrates for 16 
MHz 
> and 24 MHz but we assume that 12 MHz will be the most used crystal 
> as it provides functionality for USB and enables the 60 MHz max. 
CPU 
> speed as well. 
> 
> Sorry for not providing the appropriate values in the table for 
the 
> ISP, will update with the next reloease of the Users Manual but 
that 
> might still take a little while. 
> 
> Robert
> 
> --- In lpc2000@yahoogroups.com, "Joel Winarske" <joelw@i...> wrote:
> >
> > > To get the 48 MHz necessary for the LPC214x USB, you must use 
a 
> crystal
> > > of 12.0 MHz, 16.0 MHz, or 24.0 MHz.  None of these frequencies 
> are
> > > mentioned in the manual table 291 that lists the possible ISP 
> baud
> > > rates with various crystal frequencies.  Can you use serial 
ISP 
> with
> > > 12/16/24 MHz, and with which baud rates?
> > 
> > At 12MHz the highest the Phillips Flash utility will connect is 
> 38.4k baud.
> > I cannot connect running a higher baud. 
> > 
> > Joel
> >
>

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