Samsung S3C84E5 user manual Watch Timer, 14-1

S3C84E5/C84E9/P84E9 WATCH TIMER

14 WATCH TIMER

OVERVIEW

Watch timer functions include real-time and watch-time measurement and interval timing for the system clock. To start watch timer operation, set bit1 and bit 6 of the watch timer mode register, WTCON.1and 6, to “1”. After the watch timer starts and elapses a time, the watch timer interrupt is automatically set to “1”, and interrupt requests commence in 1.955 ms or 0.125, 0.25 and 0.5-second intervals.

The watch timer can generate a steady 0.5 kHz, 1 kHz, 2 kHz, or 4 kHz signal to the BUZZER output (BZOUT pin). By setting WTCON.3 and WTCON.2 to “11b”, the watch timer will function in high-speed mode, generating an interrupt every 1.955 ms. High-speed mode is useful for timing events for program debugging sequences.

—Real-time and Watch-time measurement

—Using a main system or subsystem clock source

—Buzzer output frequency generator

—Timing tests in high-speed mode

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