Bellevue, Wash.Here's news of a less-than-$4000 PCI bus building block board-level product that can be used to configure high channel-count systems that can sample gobs of inputs simultaneously. Microstar Laboratories, Inc., maker of DAP (data acquisition processor) boards and systems, announces its DAP 5380a/526.
It's a mid-range A/D (analog-to-digital) converter board that includes its own on-board operating system. The board is designed to work in multiples.
Using the DAP 5380a/526, you can synchronize two or more boards, installed in the same PC or in PCs on a network, to create A/D systems that sample from 16 to potentially hundreds of channels simultaneously. They will do this at 625-ksample/s speeds on each channel.
What's more, if you upgrade to the company's high-end DAP5400a/627 board, you can double that sampling rate.
Running With Windows
Microstar Laboratories's DAPstudio (or other software) is used to build and run your applications. Running under Windows, DAPstudio costs $199. You can also get unrestricted versions of both hardware and software for evaluation, at no charge, and you can download a full version of DAPstudio on the firm's Web site.
The mid-range DAP 5380a/526 board is powered by an Intel Pentium processor clocking at 233-MHz. Microstar also makes extensive use of Xilinx FPGAs (field programmable gate arrays).
Each individual board packs 16 analog inputs that can acquire 14-bit data at up to 800-ksamples/s/channel. The DAP 5380a/526 also features fault-protected input multiplexers. These MUXs permit signals to be connected to the system with power off. Analog inputs of ±25-V are accommodated.
The board's analog input connector also provides analog input expansion control lines, an external trigger input, an external input clock input, an internal input clock output, and connections to 5-V digital power and ground. Other pins provide TTL-compatible analog input expansion control signals that select an expansion port.
As mentioned above, the DAP 5380a/526 can sample eight channels simultaneously at 625-ksamples/s on each channel, for an overall throughput of 5-Msamples/s. However, if your application requires even faster sampling, you can choose a 4-channel mode. In that mode the board can sample up to four channels simultaneously at 800-ksamples/s on each channel, for a maximum throughput of 3.2-Msamples/s.
Each DAP 5380a/526 also includes 128-Mbytes of on-board memory for data buffering. The boards use DMA (direct memory access) bus-mastering to transfer data to your PC at up to the 3.2-Msample/s speed.
The board can also operate using either internal clocks or external clocks. Its crystal-controlled timers provide an internal input sampling rate and provisions for an external clock for input sampling. The system uses hardware control lines for an input clock and an input trigger. These lines are TTL compatible.
The positive-edge triggered input clock gives you two modes. In the Channel List Clocking mode, the processor starts conversion of an entire channel list on the positive edge of a clock. In Data Acquisition Processor mode, the system converts a single channel on the positive edge of the clock. The input trigger also has two modes. You can use a one-shot mode or a level-triggered gate mode.
The DAP 5380a/526 also provides a software triggering mechanism. For applications that require precise synchronization to external hardware or which are too fast to take advantage of software triggering, hardware triggering is provided. But, software triggering is more versatile than hardware triggering.
Software Triggering's Best
Except in applications with high sampling rates combined with demanding processing requirements, software triggering almost always is superior to hardware triggering. Even at the maximum sample rate, the DAP 5380a/526 has enough processing horsepower to perform software triggering, looking for simple level-crossing events. At lower sample rates, the board can scan for extremely complicated events.
When an event is detected, a task asserts a software trigger. After the trigger is asserted, another task may act, based on the assertion. The most common action is to pass a number of values around the trigger event either to another task or to your PC. The trigger mechanism is much like the trigger on a conventional oscilloscope.
Applications with more than eight simultaneously sampled channels can take advantage of the architecture's built-in synchronization feature. If an application requires 16 simultaneous inputs, each acquiring data at 625-ksamples/s, then two synchronized DAP 5380a/526 boards, installed in the same PC, can deliver an aggregate throughput of 10-Msamples/s, shared by these 16 simultaneous inputs.
An upgrade to two DAP 5400a/627 boards would double the aggregate throughput to 20-Msamples/s.
You also can synchronize two or more boards across a network. The Pentium processors, running the DAPL multi-tasking realtime operating system (optimized for data acquisition and related control functions), let you control on-board intelligence from your PC.
The system's intelligence not only protects the time-critical parts of your application from local PC delays, but also supports synchronization between hardware in different PCs on a network over a parallel DAP-to-DAP networkindependent of other network delays. Systems like this can actually comprise hundreds of channels.
As mentioned earlier, you can configure and control any DAP from your PC with DAPstudio, but Microstar's DAPtools Standard includes options for alternative development paths using applications that you may already know. With these options, you can configure and control the DAP 5380a/526 board (or any Microstar DAP board, for that matter) from programming environments such as LabVIEW, DASYLab, MATLAB, C++, or VisualBASIC. Any applications that use Windows DLLs (dynamic link libraries) can be used.
The DAP 5380a/526 board acquires data by converting analog signals and then streaming the data through so-called conceptual pipes. These pipes are pre-defined using DAPstudio. As the board's Pentium transfers data from pipe to pipe, it also carries out the operations you specify in DAPstudio.
A typical application may require six or seven of onboard operations (from more than 100 DAPL commands that are available). In many cases you can use DAPstudio to run your application, from any PC on a network, with no custom programming and no other vendor software.
Microstar Laboratories also offers a number of accessories and cardcage enclosures for its DAP boards. The company's high-density industrial enclosures support data-acq systems with many signals or with multiple isolation, counter, or sensor interface boards. Rack-mount enclosure options include full-size 19-inch and also half-size models.
Shielded cables and connectors are also used to bring clean signals inside to termination and accessory boards. Shielding is maintained all the way through to the converters on DAP 5380a/526 boards. For very high-channel-count applications, multiple industrial enclosures can be cabled together to make one connected system.
Click here for a table of specs Web page, and links to related documents, including a user's manual.
For further information contact Microstar Laboratories Inc., 2265 116th Ave. NE, Bellevue, Wash. 98004425. Phone: 425-453-2345. E-mail: firstname.lastname@example.org
Microstar Laboratories, 425-453-2345 www.mstarlabs.com