Lpc2000

On Mon, 02 Feb 2004 08:34:01 -0800, Brian C. Lane wrote:

I'm working on designing a new project where we need to process 9600bps 
packets (similar to G3RUH format), we'd like to use the LPC2106 which 
ought to be fast enough. But I'm having trouble coming up with a 
suitable  ADC. It needs to sample at 48khz, 10 bits are fine, 2 
channels. It needs to be consistent (no jitter).

I could use a SPI ADC with the ARM as the SPI master, but I'm afraid 
that other interrupts in the system will effect the sample accuracy (it 
will also be doing some serial communications and have some timers 
running) and introduce jitter into sample rate.

Ideally the ADC would be a SPI master with its own reference clock, 
feeding the samples to the ARM with some indication (high bit 
set/clear?) of which channel the data came from. There are some AKM 
ADCs/codecs that might work, but their left/right clock would somehow 
need to be associated with the data -- hard to do if you have a delay in 
getting to the interrupt to process the data and L/R has already 
switched to the other channel.

=======================================================================
Brian
  This should be available soon.
-Bill Knight
R O SoftWare

ARM-based Microcontroller LPC2114/2124/2212/2214

A/D CONVERTER FEATURES
" 10 bit successive approximation analog to digital converter.
" Input multiplexing among 4 pins (LPC2114/2124) or 8 pins (LPC2212/2214)
" Power down mode
" Measurement range 0 to 3 V
" 10 bit conversion time >= 2.44 uS
" Burst conversion mode for single or multiple inputs
" Optional conversion on transition on input pin or Timer Match signal