Lpc2000

Can't seem to get the RX FIFO on UART0 to work...
 
My setup:
 
U0IER bit 0 =1, Enabled RDA interrupt (receive data interrupt)
U0IER bit 1 = 1, Enable THRE enterrupt (transmit data interrupt)
U0IER bit 2 = 1, Enabled the Rx line status interrupts
 
U0FCR bit 0 = 1, Enabled both RX and TX FIFOs
U0FCR bit 7:6 = 3, Rx trigger level of 14 chars
 
The TX and RX interrupts work it's just that RX interrupts immediately
after receiving a character.  I'm running at 38.4k baud and I'm getting
an interrupt every 286uS which is the char time at this baud rate.  I'm
expecting to not interrupt until 14 characters have come into the
buffer.
 
Any ideas or anyone else having this same problem?
 
Thanks, Jeff.

	-----Original Message-----
	From: lpc2000@yahoogroups.com [mailto:lpc2000@yahoogroups.com]
On Behalf Of embeddedjanitor
	Sent: Monday, May 02, 2005 1:37 PM
	To: lpc2000@yahoogroups.com
	Subject: [lpc2000] Re: What's Best Way to Globally Disable
Interrupts
	
	
	--- In lpc2000@yahoogroups.com, Robert Adsett
<subscriptions@a...> 
	wrote:
	> At 07:30 PM 5/2/05 +0000, kaiandxiulpc2000 wrote:
	> >If my user application is running with interrupts occurring,
then I
	> >need to disable all interrupts for a bit of time:
	> >
	> >1) Should I use the C command "VICIntEnable=0x00000000"?
	> >OR
	> >2) Set the IRQ and FIQ bits in the cpsr?  Also, then do I
have to 
	be
	> >in
	> >non-user mode (i.e. privileged mode) to enable/disable the
IRQ/FIQ
	> >bits
	> >in the cpsr?
	> 
	> In my opinion number 2 will cause you the least problems.  In
fact I 
	would 
	> disable interrupts before modifying VICIntEnable. And yes you
have 
	to be in 
	> a mode other than user mode.  On the other hand there is no
reason 
	to be in 
	> user mode anyway.  The only thing that distinguishes user mode
from 
	system 
	> mode is that in user mode is that in user mode you cannot set
and 
	clear the 
	> interrupt enable bits.
	
	Agree. Look back for postings on spurious interrupts. Fiddling
with 
	the VIC is not enough.
	
	
	> 
	> Personally I prefer a disable/restore interrupt pair rather
than a 
	> disable/enable interrupt pair.  There is an implementation of
the 
	former in 
	> the newlib-lpc library that should be easily separable from
that 
	library if 
	> desired.
	
	Agree again.
	
	restoring allows you to restore the previous state (ie. you
should not 
	always blindly turn interrupts on). Restoring allows you to use
the 
	same code in an interrupt or normal context etc.
	
	I use two funtions  intGetDisable() and intEnable()
	
	  int intval; // previous interrupt value
	
	  intval = intGetDisable(); // Is the interrupt enabled? Disable
if it 
	is enabled;
	  // protected code
	
	  if(intval) 
	      intEnable();
	
	
	
	
	
	
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