Lost & Found - Styx for the IBM PCjr. Demonstration
0Most people who know anything about early IBM PC software know about WIndmill Software's hardware bending games. Its games may have been ports of well-known arcade games, (Conquest = Joust, Digger = Mr. Do etc.) but the presentation frequently tweaked the CGA graphics and PC Speaker sound hardware and the 8088 CPU as far as possible. Its games are also very hard to get running on systems significantly more advanced than the IBM PC or XT.
One of Windmill Software's better known titles is Styx, and the name of its arcade forebear shouldn't stump anybody. (Hint: it rhymes.) Styx's release for the IBM PC is well-known and has been freely available for a very long time. It does not run properly on an IBM PCjr., a platform with hit-or-miss compatibility with IBM PC hardware. What is less well-known is that Windmill Software specifically released a version of the game for the IBM PCjr., and I have long wanted to know what differences there were between the PC and PCjr. versions.
Just within the past month, a number of individuals dedicated to preserving PC software have finally been able to dump the copy-protected disk of Styx for the PCjr. off a single known disk (Servo), and crack the protection and convert it into a DOS-runnable program (NewRisingSun).
Here is my capture of the game on my genuine IBM PCjr. I used my Datapath VisionRGB E1s with VCS and OBS to capture the video. I captured the whole IBM PCjr. boot process. Styx was originally a self-booting disk and appears to know nothing about PCjr. memory expansions, so it is a much slower game when booted from the base 128KB. Running it in DOS with the memory driver loaded will make the game run much faster than the PC version running on an IBM PC. I would have liked to capture the PC version as well, but it is very unfriendly toward the Datapath. I booted a PC-DOS DOS 2.1 floppy disk instead of the hard drive to avoid loading the memory manager that makes the game go too fast.
The main difference between the PC and PCjr. versions of Styx is the use of the PCjr. sound chip, the TI SN76496 for the sound effects and music instead of the PC speaker. The PC version runs faster than the PCjr version. The PC version can also move the line diagonally due to its numeric keypad, the PCjr. can only move the line diagonally with a joystick. I captured a 720x240 window to show that this version, unlike the PC version, does not show border colors. It also helps to capture a larger window because the active display can shift itself horizontally or vertically when a mode change occurs. The Datapath shows wrong colors with in a 640x200 graphics mode when borders are display for reasons unknown to me. Styx showed a brown border on in the PC version.