Lpc2000

Hi Martin,

there are no immediate plans to use the fractional baudrate 
generator because we try to keep the number of different bootloaders 
limited. Also it is very difficult to use the fractional BR 
generator if the frequency of the oscillator is not known.
Last but not least it is not possible to go 921 kbaud with 12 MHz 
because the max serial frequency with or without fractional baudrate 
generator is CPU clock divided by 16 and the bootloader does not 
change the PLL settings.

Regards, Robert

--- In lpc2000@yahoogroups.com, "Martin Maurer" <mailingliste@c...> 
wrote:
>
> Hi Robert,
> 
> is there any plan to use the fractional baudrate generation in the 
booter,
> so you can boot e.g. even at 921 kbit/s with a 12 MHz oscillator ?
> Theoretically it should be possible, hardware is supporting it...
> 
> Regards,
> 
>          Martin
> 
> ----- Original Message ----- 
> From: "philips_apps" <philips_apps@y...>
> To: <lpc2000@yahoogroups.com>
> Sent: Friday, November 18, 2005 12:12 AM
> Subject: [lpc2000] Re: LPC214x crystal frequencies // ISP max 
baudrate 38.4 
> kBaud using 12 MHz
> 
> 
> > Confirmed
> >
> > 12 MHz  ->  max baudrate 38400
> > 16 MHz  ->  max baudrate 19200
> > 24 MHz  ->  max baudrate 38400
> >
> > Robert
> >
> > --- In lpc2000@yahoogroups.com, "seangra" <sgraham@o...> wrote:
> >>
> >> 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
> >> > >
> >> >
> >>
> >
> >
> >
> >
> >
> >
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
> >
>