From: Daniel R. <di...@gm...> - 2010-01-30 07:46:58
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On Sat, Jan 30, 2010 at 1:01 AM, Dave Hylands <dhy...@gm...> wrote: > You'll probably need to get a dedicated A/D converter that connects > via i2c or SPI. > Maxim has a bunch, and you can often get free samples: > <http://www.maxim-ic.com/products/data_converters/adcs/> > > You probably won't be able to sample 10v directly, but you can feed it > into a resistor divider, and scale the voltage down to 0-5v. When you > pick your resistors pick ones with a fairly %. Resistors are normally > 5% tolerance. You can get 0.1% or 0.01% etc. I figured I would need a dedicated ADC. There might be some 0-10V ADCs out there. Wouldn't MAX1272 work? <http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3998> The next question is how do I read data on the gumstix using the ADC? I've never used SPI before, so I'd like some clarification on where I connect the four wires used between the ADC and gumstix. In the sample code for SPI (http://docwiki.gumstix.org/Sample_code/C/SPI) it mentions that SPI is used via certain NSSP pins. What/where are the NSSP pins? Avast! Daniel Roesler di...@gm... |