DVME-601E Datel A/D Co-Processor Board

Designed for today's VME environment of real-time operating systems and busy host processors, DATEL's DVME-601 is a high performance A/D data acquisition system integrated with a local 68010-based single-board microcomputer. The DVME601 smart A/D board performs simultaneous analog data collection while concurrent VME host processing continues. Unlike dumb A/D boards, the DVME-601 will automatically collect scans without delaying other host software tasks. When A/D data is ready, the 601 can interrupt the VME host so that the host can memory transfer previous scans without stopping collection of the next scan.

Typical applications for the DVME-601 include high speed process control loops, analytical instruments, research laboratories, vehicular data recorders, ATE equipment and communications testers. The block oriented, interrupt controlled, memory transfers of A/D scans to the host are particularly suited to Digital Signal Processing applications in acoustics, sonar, high speed mapping, seismology, medical imaging, graphics, array processing, FFT's and waveform analysis. Using the single-channel fast-throughput mode and 2 microsecond converter, true 12 bit speeds over 250,000 samples per second to memory are available (single-channel, gain=l).

The data acquisition section includes an analog input multiplexer with 16S/8D local channels expandable up to 256 total channels using DATEL's slave MUX boards. An Instrumentation Amplifier is included which may be resistor-programmed by the user up to a gain of 1000. A choice of pluggable A/D Converter modules is offered on five different models. Resolution from 12 to 16 bits is available with 12-bit conversion speeds down to 2 microseconds.

A/D conversion may be started by external trigger, internal programmable timer, by local programs and in-directly by host command. All of these start modes are managed by on-board EPROM firmware. A DC/DC converter supplies low-noise regulated power to the data acquisition section.

The primary interface between the 601 coprocessor and its VME host is a 64 Kb dual ported Random Access Memory (DPR). The DPR is used for commands, subroutines and parameters, control / status bits, AID data blocks, optional downloads of user programs, and bidirectional interrupts between the 601 and the host. The maskable interrupt to the VMEbus normally occurs after A/D scanning but may also be commanded from a local user program.