Latest version: 16 August 2000.
Download: TWY16.ZIP complete package (77,234 bytes).
Download: TWY16A.ZIP .COM file only (3,938 bytes).

Taxiway (TWY in short) is yet another PS1 add-on program that displays airport taxiways in a plan view on the lower EICAS screen. You can program your own airport diagrams using the TWY Maker tool (under development).

Screenshots:
PS1 lined up runway 31L at KJFK New York:

Airports with converted ProController sector (.SCT) files

EBBR EDDF EDDH EDDK EDDM EDDT EGLL EHAM
LOWI LOWW LFML LFPG
KBOS KIAD KJFK KORD
YBBN YMML YPAD YSCB YSSY

System requirements

• Precision Simulator version 1.3.
• at least 26 kilobytes free conventional or upper memory space, in addition to that required by PS1.3.
• enough XMS (eXtended Memory System) memory for the SCENERY.TWY file.
  XMS memory is provided by HIMEM.SYS, and should automatically be available under Windows(tm).

Installation and usage

1. Install TWY in any directory you like. Make sure the SCENERY.TWY file is in the same directory as the TWY.COM program file.
2. If running in Windows: open up a DOS prompt window so that you obtain a prompt to enter commands at.
3. Start TWY with the command lh twy. The lh (LoadHigh) loads TWY into Upper Memory if 26kb are available. Otherwise TWY will be loaded into conventional (lower) memory.
4. Now start PS1 using ps. (Use 747 if not running in Windows. See page 10 of the PS1.3 Operations Manual.)
5. When PS1 is loaded up, blank the lower EICAS. Now press F11 to bring up the TWY display on the lower EICAS. See screenshot above.

   TWY uses the active Origin and Destination airport entries on the CDU ROUTE page to determine which airport to display. On startup, the Origin airport will be displayed. To switch to the Destination airport, press Ctrl-F12.

   If your airplane is not positioned at the airport, you will not see the taxiway display !

   The displayed airport code will be '----' if the selected airport does not exist in the SCENERY.TWY database.

6. To zoom in on the map display, press F12. The zoom factor is indicated on the bottom right corner of the EICAS screen. It is initially 12 (large-scale), and each press of F12 will zoom in by a factor of 1, until factor 8 (small-scale) is reached. A subsequent keypress will revert back to factor 12.
7. Press F11 to hide the TWY display.
8. After quitting PS1, type twy r to remove TWY from memory.

   The entire process of starting TWY then PS1 from the same DOS window can be automated by means of a batch (.BAT) file. I have supplied one example batch file in the TWYxx.ZIP, called "T.BAT", which should work in most cases. You are at liberty to modify this file to suit your own system setup.

Credits
Thanks to Jim Dukat for his advice in the early stages of development,
to Dusan Lacko & Martin Erdelen for bravely exposing their PCs to the risks of untested code,
to Jeroen Hoppenbrouwers for his wild ideas and staunch stand on free software,
to all creators of the ProController ground maps for their lovely creations,
to Arturo Sandoval whose music occupied my mind during the times when I was cracking a tough bug,
and to Hardy Himself for writing PS1.3 as a DOS app giving hackers like me a reason to live on...