compucolor

The compucolor also another failure mode; it is a rare example of how a software bug can cause physical damage. The compucolor logic is stuffed inside a normal TV case (there are even empty holes for tint/brightness/contrast along the bottom and a convenient carrying handle on the top) with the board driving baseband video to the normal TV logic. The CRT timing is generated by a chip that has timing registers loaded from an on-chip ROM. However, the CPU is free to write new values to the timing registers, and if the wrong value is entered, it causes something dire to happen in the TV section's logic (eg, if the horizontal frequency is too low then the flyback transformer's impedence drops and draws a lot of current and smokes).