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My first assignment was to perform some testing of the new video chip and plot a chart of chip operations versus supply voltage and temperature. While waiting for the temperature chamber to stabilize during these test, I was reading the detailed chip specifications and came to a startling discovery -- there was a new graphics mode in this chip which would allow neat new applications. At the same time, the Editor/Assembler (E/A) cartridge was in the early stages of alpha (internal) testing. I used the E/A cartridge to play around with the new graphics mode (Graphics Mode II). One of the first programs I wrote was a simple line-drawing program which was bundled with the Mini Memory module.
After I wrote the Lines program, management moved me from the hardware to the R&D group and suggested that I collaborate with [[Jim Dramis]] on a new game. I thought this was better than sex (OK, I WAS kinda naive) -- getting paid to write a video game. Just for reference, Jim had written some of the best TI games available at that point -- [[Car Wars]] and [[MunchMan]]. We quickly agreed that we wanted to write a space game and we wanted to have smooth horizontal scrolling to give the illusion of flying over the surface of a planet. As some of you may know, there is NO hardware support for scrolling the screen on a pixel basis in the 99/4A video chip. After lot's of pondering, I hit upon a solution -- copy the inner loop of the scroll code into the fast 16-bit RAM of the 99/4A. Since this code is responsible for 80% of the execution time of the scroll loop, substantial speed gains were made by moving the loop to fast RAM. In today's world of 486s and Pentiums, this RAM would be referred to as cache RAM. I then handed this code off the Jim so he could incorporate it into the game.
[[Category:Software programmer]]
