RotorDRV TSR Add-On to Display Az/El Angles

Must Be Art > Software > DISPANG


DISPANG is a DOS TSR (terminate-and-stay-resident) program for use with antenna rotator drivers compatible with the programming interface defined by the Kansas City Tracker (KCT). This interface allows application programs, especially satellite tracking programs such as InstantTrack, to control a two-axis antenna rotator without needing to know any details of the hardware. The hardware driver, referred to as RotorDRV, is installed as a TSR program, and accepts commands through software interrupts. DISPANG installs as a second TSR on top of RotorDRV, and monitors the commands being sent from the application program to RotorDRV. When it sees a command to set the current azimuth and elevation, it displays the values in the upper right corner of the computer's text screen.

System Requirements

To run DISPANG, any environment capable of running an MS-DOS TSR program is required. This certainly includes all versions of MS-DOS beyond 2.0. This program will also work under all versions of Windows or OS/2, but the underlying RotorDRV may or may not work satisfactorily in such environments.




The annotated screen shot below shows InstantTrack 1.54 running in realtime text mode with DISPANG installed.

Current Status

Stable. No current development plans. The current released version is 0.5, released April 22, 1990.



Known Bugs



DISPANG maybe distributed freely and may be used freely for non-commercial purposes only.

Source Code

Source code in assembly language for Microsoft MASM 5.1 is included, with a Microsoft MAKE makefile for each version.


DISPANG.TXT - user manual (plain text, 4K)

DRVSVC.TXT - programmer's specification for the KCT software interface

INTSPEC.TXT - programmer's specification for the interfaces used by OrbitDRV

KCT-passthru - programmer's specification for KCT TSR extensions


DISPANG 0.5 (zip file, 7K)

Copyright 2002 Paul Williamson. Comments to kb5mu@amsat.org