The M-1 Worm

Personal Computing

July 1979


This was a computer program disguised as an article. It was a memory tester for Z-80. I called it a worm because the code itself crawled up through memory space. This was the only way to test a particular quirk of Z-80 memory -- instruction cycles made more demands on memory than data cycles. I talked to a person years after who recognized me as the author of this program because some computer vendor had packaged this program into their suite of utilities. I had never known about it. Oh, well...the perils of selling all rights to an article.