10 bit $US24.95   4 analogue in, 2 digital in, 240 samples/sec
Serial port interface, Software

            http://www.dataq.com/products/startkit/di194rs.htm

12 bit $US149.95  4 analogue in, 2 digital in, 240 samples/sec
1 digital output, square wave generator, Serial port interface, Software

        http://www.dataq.com/products/startkit/di154rs.htm


+/- 10 volt inputs in each case giving around 2 mV resolution for 10 bit
version.

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