Lpc2000

Ken

the difference between the 2214 you are using and the 2294 the
question was about are 4 CAN interfaces.  CAN works at baudrates like
1 Mbit/s 500 kbit/s, 250 kbit/s..  you get the message.  While CAN is
highly dependend on the accuracy of the clock the UART can be off by
2.5 % and that is nothing about a good or bad idea, it is just how
much both, sender and receiver can be off and still get a valid
message across.

So, 11.059 or similar crystals can not work with CAN unless a very
powerful PLL would be implemented.

As mentioned in my previous post, it is possible to run 115200 from 60
MHz, in particulat when talking to a PC which is usually very accurate
with the baudrate.

Hope this help clarifying the issue, Bob

--- In lpc2000@yahoogroups.com, "Ken Wada" <kwada@a...> wrote:
> --- In lpc2000@yahoogroups.com, "SR" <emddjava@y...> wrote:
> > I saw a previous post that stated that the LPC2xxx can reach
> > 115200kbps without modification, How do you do this? I can't seem to
> > get the data right at 115200
> 
> ok...You MUST do the following:
> 1.  In general, you MUST design in your main clock crystal to be some 
> multipe of 9600. Personally, I use 11.0592Mhz, 14.7456Mhz and 22.
> 1184Mhz.
> 
> 2.  Most PC UARTs can accept small variances from the 9600/schema, but 
> in general, it is not a good idea to do this!
> 
> 3.  Next, you MUST get your UART device driver fully operational at 
> 9600 baud, or some slow reliable baud rate...then later, kick the 
> thing up to 115200
> 
> I am currently using an LPC2214 on several projects with 115200, and 
> the thing seems to be working fine.
> 
> I also, have written a full interrupt-driven service routine. At these 
> 115200 speeds, it is a good idea to make your service as 
> time-efficient as possible...Plus it is a VERY good idea to enable 
> those 16-deep FIFOs when operating at 115200 baud
> 
> Ken Wada