Flash-Based Factory PCMs – Tech – In A Flash
In 1984, while we all marveled at the news of General Motors’ stunning new Tuned Port Injection debuting on ’85 Vettes, a far more important automotive technological breakthrough was taking place at Toshiba. Okay, so it wasn’t exclusively or intentionally an ‘automotive’ technology, but the 1984 invention of ‘Flash Memory’ by Toshiba’s Dr. Fujio Masuoka made more of an automotive impact than we’d have ever expected. Besides becoming the memory of choice for digital cameras, USB thumb drives, and computer BIOS, flash memory also became the first choice for automotive control computers. Before flash arrived, automotive computers relied primarily on erasable programmable read-only memory microchips, aka EPROMs or just ‘chips’ for short. EPROMs generally worked fine as memory devices, but ultimately reached demise from two key disadvantages: high cost and poor serviceability. The cost of the quartz-laden chip itself was expensive, and making it easily removable for service made the computer more expensive as well. Reprogramming an EPROM is a laboratory-like process involving chip removal, UV-light erasure, and chip ‘burning.’ In other words, dealership reprogramming was out of the question; service or updated programming meant chip replacement. When the flash memory technology reached commercialization, it was a sure bet to replace the EPROM. Flash-based memory was comparatively inexpensive, and reprogramming was a rudimentary process that could now be done through the assembly line diagnostic link (ALDL) connector.