Lpc2000

Yes, you are missing something.

THRE indicates when FIFO is empty - not when it is full.
Furthermore, the exact time when this occurs, depends 
on "initialization conditions".
See paragraph following Table 68 of LPC213x manual (or similar for 
other members of this family).

As far as using TEMT for RS-485 turn-around, that would be great if 
it could be used to generate an interrupt.


--- In lpc2000@yahoogroups.com, "Bill Knight" <BillK@t...> wrote:
> Am I missing something here guys (and gals)?  When the FIFO is
> enabled the THRE bit in the Line Status Register is set whenever
> the FIFO can accept additional characters.  So if it were clear,
> isn't that an indication the FIFO is full?
> As for RS-485 transceiver turn-around; the TEMT bit also in the
> Line Status Register, can be used to determine when the stop bit
> of the last character has been transmitted.  Can't that be used
> to control the RS-485 interface?
> 
> Regards
> -Bill Knight
> R O SoftWare &
> http://www.theARMPatch.com