Digital Filter Design & Simulation

DISPRO Background
DISPRO Features
DISPRO User Manual
DISPRO Download
StoZ Background
StoZ User Guide
StoZ Download
Contact Me
Guest Book
Win7 Operation



When DISPRO was first written and developed in 1982-1983, only the BASIC interpreter (and later the IBM-Microsoft BASIC compiler) was available to support the color graphics capabilities of the IBM PC.  It would be tedious to document the many upgrades which DISPRO has undergone the last major upgrade, to ver. 2.5, was performed in 1996.  DISPRO has remained coded in Microsoft BASIC specifically, Professional BASIC 7.1 with certain library functions in assembly language.  Many enhancements have been made to DISPRO, as recently as 2005, while still retaining the ver. 2.5 label.

Because of its DOS legacy there are certain limitations when DISPRO is executed under Windows:

  • Graphics resolution is limited to EGA (640x350), except for the graphical display of sinusoidal response in the time-response module where VGA (640x480) resolution is used.

  • Hard copy output of graphics is limited to HP LaserJet or DeskJet (or a PCL-compatible printer),  and Epson/IBM graphics-compatible dot-matrix printers.

  • Any printer used with DISPRO must be connected to the LPT1 parallel port (USB printers are not supported).

  • Text-mode screens are OK in a window but graphics screens can only be updated in full-screen mode: use Alt-Enter to switch between display modes.  (In Win 95, 98, and NT the graphics screen can be displayed in a window, but not in XP.)

  • All file names are restricted to the DOS style of eight characters with a three character extension.

 As was true for all early DOS applications, DISPRO is constrained to use only 128 kilobytes of memory 64 kB for code, and 64 kB for data.  Consequently, the design of DISPRO is highly modular: the 16 executable modules function as a unit through the CHAINing capability of BASIC.  Almost all data related to the filter under design,  or analysis,  is stored in a disk file which can be accessed by any executable module as necessary.

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