Wavetronix Click 500 (programmable controller) (CLK-500) - Developer Guide - Manual (Page 58)

In this chapter
˽ The OS and Timer Interrupt
˽ Cooperative Multitasking
˽ Watchdog Timer
˽ Real Time Clock
˽ Example Code 6.1
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TThis chapter gives an overview of the operating system that powers the Click 500 proces-
sor. It explains how to leverage the full processing power of the platform when you have a
demanding application. The chapter also contains information on how a watchdog timer is
used to limit the amount of time that the device is in an unknown or unresponsive state and
how the real-time clock can be used to schedule long term events.
The OS and Timer Interrupt
The basic input/output system (BIOS) initializes the Click 500 platform and puts it in a
known state before the Dynamic C main function executes. The main function then ex-
ecutes the current operating mode in a continuous loop unless interrupted by some mecha-
nism. For example, if the push button is held, then the current operating mode or task is
suspended until a new one is selected. Another interrupt mechanism is an interrupt timer
that by default fires about 90 times a second.
Timers and Clocks
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