During this test, QuickTech Self Boot loads a count into each of the three timer channels and then verifies that each channel counts down at the correct pace (not too fast or too slow).
Timer Channel 0 is implemented as a general purpose timer providing a constant time base for the time-of-day clock. It is tied in directly to the Interrupt Controller’s Channel 0 and cycled 18.2 times a second (54.936 millisecond resolution). Timer Channel 1, which is the most important of the three, is cycled every 15.12 microseconds. It is used in the dynamic memory refreshing routing to ensure that a full refresh cycle is initiated at least once every two milliseconds. Timer Channel 2 is used to generate a sine wave, which is routed to the speaker. Unlike Channels 0 and 1, Channel 2 is not as critical to a system’s operation since it is used to produce audio signals.
Systems that speed up the timer to gain better performance may fail Timer Channel 1. This failure is a compatibility failure and can be ignored if the system is not having unusual hang-ups or intermittent failure.