Model MicroCEM

Instruction Manual

748467-A January 2002

c. Programmable Input Ranges

e. Analog Outputs

A programmable gain amplifier, programmable unipolar/bipolar range, and programmable 5V/10V full-scale range combine to give the ADIO board a total of 10 different possible analog input ranges. All range settings are controlled in software for maximum flexibility.

Mode

Full-

Gain

Input

Resolution

scale

Range

Unipolar

10V

1

0-10V

0.153mV

Unipolar

5V

1

0-5V

0.076mV

Unipolar

5V

2

0-2.5V

0.038mV

Unipolar

5V

4

0-1.25V

0.019mV

Unipolar

5V

8

0-0.625V

0.0096mV

Bipolar

10V

1

±10V

0.305mV

Bipolar

5V

1

±5V

0.153mV

Bipolar

5V

2

±2.5V

0.076mV

Bipolar

5V

4

±1.25V

0.038mV

Bipolar

5V

8

±0.625V

0.019mV

d.Enhanced Trigger and Sampling Con- trol Signals

The ADIO board has an extra A/D trigger and sample control signals in the design. Seven auxiliary digital I/O lines on the analog I/O connector provide a sam- ple/hold output signal, A/D trigger in and out lines (to enable synchronization of multiple boards) and external A/D clock- ing.

The ADIO board contains 4 12-bit analog outputs with autocalibration capability. Up to 5mA of output current per channel can be drawn from all channels simultane- ously. Both unipolar and bipolar output ranges are supported with jumper con- figuration. And on power up, all outputs are reset to 0V automatically.

Mode

Full-

Output

Resolution

scale

Range

Unipolar

10V

0-10V

2.44mV

Unipolar

5V

0-5V

1.22mV

Bipolar

10V

±10V

4.88mV

Bipolar

5V

±5V

2.44mV

f.FIFO and 16-Bit Bus Interface

An on-board 1024-byte FIFO enables the ADIO board to work with Windows 95 and NT by dramatically reducing the interrupt overhead. Each interrupt transfers 256 2- byte samples, or half the buffer, so the interrupt rate is 1/256 the sample rate. FIFO operation can be disabled at slow sample rates, so there is no lag time be- tween sampling and data availability. The 16-bit interface further reduces software overhead by enabling all 16 A/D bits to be read in a single instruction, instead of re- quiring 2 8-bit read operations. The net result of this streamlined design is that the ADIO board supports gap-free A/D sam- pling at rates up to 200,000 samples per second, twice as fast as our previous boards.

Rosemount Analytical Inc. A Division of Emerson Process Management

Description and Specifications

1-11