By 1996 Digital Eclipse had established a reputation for building pixel-perfect emulators of coin-op arcade machines.

The SNES console wasn't fast enough to run an emulator, so for Williams' Arcade Greatest Hits the team decided to hand translate Williams' original 6809 assembler source code into the Super 6502 assembler used by the SNES.

Jeff Vavasour translated Joust, Defender, Defender 2, and Robotron. I translated Sinistar which differed from the others because it rotated the CRT 90°to achieve a unique aspect ratio.

We couldn't ask SNES users to rotate their television sets! I moved the heads-up display from the top to the right side of the screen, and allowed the player to show or hide it using a trigger button.

This kind of project is like translating poetry: you're expressing the logic of the game in a different computer language and environment, without changing how it feels to the player. Here's some (unrelated) 6809 code before and after translation to Super 6502.