Lpc2000

I noticed the comment on 'proper UART' operation also.

I have used both the 16c550 and the 16c450 for many years. My 
recollection is that the FIFO enable bit was supposed to change the 
mode to 16c450 'FIFO-less' operation when disabled; and change the 
mode to true 16c550 mode when enabled.

In fact, the National Semiconductor datasheet on the 16c550 says the 
following:

Bit 0: Writing a 1 to FCR0 enables both the XMIT and RCVR
FIFOs. Resetting FCR0 will clear all bytes in both FIFOs. When 
changing from the FIFO Mode to the 16450 Mode and vice versa, data is 
automatically cleared from the FIFOs. This bit must be a 1 when other 
FCR bits are written to or they will not be programmed.

It was my understanding, according to the LPC2xxx user's manual, and 
datasheet that, (other than not supporting the DMA operation), that 
these UARTS are supposed to be 16c550 clones.

Ken Wada

--- In lpc2000@yahoogroups.com, "lp2000c" <lp2000c@e...> wrote:
> 
> Beware the fine print that FIFO enable bit must be set for proper 
> operation of the UART!
> 
> 
> --- In lpc2000@yahoogroups.com, "Ken Wada" <kwada@a...> wrote:
> > 
> > There are two ways to do this:
> >   1. Disable the FIFO enable bit on the FIFO control register
> >   2. Set the Tx FIFO reset bit ont the FIFO control register
> > 
> > Ken Wada
> > 
> > --- In lpc2000@yahoogroups.com, Gerhard Unrecht <unrecht@p...> 
> wrote:
> > > Hey,
> > > 
> > > I want to clear the transmit-Fifo, to have a defined state.
> > > Knows anybody how to do do this?
> > > 
> > > Regards
> > > 
> > > Gerhard Unrecht
> > > 
> > > 
> > > [Non-text portions of this message have been removed]