This article appeared in Personal Engineering & Instrumentation News in April 1997.
Relatively new as a standard for the x86 world, 32-bit operating systems provide speed enhancements over older 16-bit operating systems to programs that utilize extra data bandwidth. Taking advantage of these new OSs, DSP Development Corp (Cambridge, MA (617) 577-1133) has updated its DADiSP 4.0 analysis package. The release of a native Win95/NT version ($1995) enhances both speed and usability. NT users benefit from an execution speed increase of as much as 30%, but Win95 users don't experience this speedup -- holdover 16-bit portions of the OS limit the execution speed of the upgrade. According to the vendor, Win95 users should expect the program to run at the same speed as non-native Ver 4.0. Native-mode compilation also offers immediate execution speed increases to users calling external DLLs. Its operation provides the ability to call external 32-bit DLLs and generates code inherently faster for both Win95/NT than code compiled in 16-bit mode.
In addition, the developers improved the package's data-import capability. Users manipulate data as channels, which might represent a single column of numbers within a multiple-column datafile. Previously, if an import required more than one channel of data, users invoked a separate text editor to specify a header file to instruct the program to import and label separate channels. Now a menu-driven import generator guides users through the process of deciding the name, number of samples, sampling rate, any offset or rescaling and units of a channel. Users can also select specific channels to import from a multichannel file.
The windows that make up a typical session in DADiSP 4.0 not only graphically plot or tabulate data but also give a step-by-step report on each stage of an analysis or transform. Win 95/NT GUI enhances this form of visual feedback through tools that zoom in and scroll over portions of plots without rescaling.
A command-line interface provides an alternative to those preferring to type in a selection. A standard Win95/NT drop-down combo box now records the last 30 commands and allows replay of functions. These combo boxes also implement automatic command completion: typing the first several characters of a memorized command followed by hitting F4 brings up the entire command.
Finally, SPL, the compiled language that allows users to add custom functions, now supports multiple return values, thus functions can return values to separate variables. Programmers should also feel at home with the addition of pointers to variables, explicit local-variable definitions and compile-time error messages that include the line number of the problem.
Copyright 1997 PEC Inc. at
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