PMC-16AIO-88-31 General Standards Analog I/O PMC Module

The General Standards PMC-16AIO-88 board contains eight 16-Bit D/A converters, an 8-channel 16-bit scanning A/D converter, and all supporting functions necessary for adding flexible analog I/O capability to a PMC host. The board is functionally compatible with the IEEE PCI local bus specification Revision 2.3, and supports the "plug-n-play" system initialization concept. Designed for minimum off-line maintenance, the PMC-16AIO-88 board includes internal monitoring and loopback features that eliminate the need for disconnecting or removing the module from the system for calibration. A shared programmable rate generator provides a time base for controlling either output clocking or input scanning, or permits input scanning be synchronized to the output clock. All system analog input and output connections are made through a single 50-pin subminiature-D front-access I/O connector.

Offset and gain trimming of the input and output channels is performed by calibration DACs that are loaded with channel correction values during initialization. During autocalibration, system analog inputs are replaced with either a precision voltage standard or the eight analog output channels. This arrangement is used to determine the necessary offset and gain correction values for the calibration DAC's. The correction values determined during autocalibration are stored in an EEprom for subsequent transfer to the calibration DAC's during board initialization.

The board receives output data and channel identification values through an analog output (AO) buffer. Analog input conversion values are transferred to the bus through an analog input (AI) FIFO buffer. A PCI Interface Adapter provides communication with the host PCI bus, and furnishes a 16-bit local bus for exchanging information between the FIFO buffers, the adapter, and the Local Controller. The Local Controller manages all internal operations.