Lpc2000

--- In lpc2000@yahoogroups.com, "wittrockjeff" <jwittrock@m...> wrote:
> 
> Hello All,
> 
> I have not used any of the LPCxxx devices before.  I am considering 
> using an LPC2138 in an application which must read data from an 
> ADS1271 24bit A/D using an SPI interface.
> 
> In looking at the SSP specification for the LPC2138, it can handle a 
> maximum frame size of 16 bits.  Does anyone know of a way to extend 
> this to 24bits without CPU intervention? Has anyone done something 
> similar?  The ADS2171 will have a 100kHz data rate, so I'm worried 
> about having interrupts on a Byte by Byte basis, as that would be a 
> 300kHz interrupt rate (100kHz X 24/8).
> 
> Thanks for any help.
> Jeff
> 
> p.s. Great user group.  Lots of good info.

Hi Jeff
we are using 2138 with and ads1251 but only at 9.6Khz the problem we
had running at faster rates is processing the data at the current rate
we only have 104us to work with between measurements at 100Khz this is
down to 10us not sure about the 1271 but the 1251 requires some block
averaging of readings to achieve the the maximum resolution is this case?

paul