beautypg.com

Analog input register group – National Instruments Low-Cost Multifunction I/O Board for ISA Lab-PC+ User Manual

Page 131

background image

Appendix D

Register Map and Descriptions

© National Instruments Corporation

D-15

Lab-PC+ User Manual

Analog Input Register Group

The four registers making up the Analog Input Register Group control the analog input circuitry
and can be used to read the FIFO. Reading the FIFO Register returns stored A/D conversion
results. Writing to the Start Convert Register initiates an A/D conversion. Writing to the A/D
Clear Register clears the data acquisition circuitry. Writing to the DMATC Clear Register clears
the interrupt request generated by a DMA terminal count pulse.

Bit descriptions for the registers making up the Analog Input Register Group are given on the
following pages.