Samsung KS57C2308 manual Buzzer Output Frequency Generator, Timing Tests in High-Speed Mode

KS57C2308/P2308/C2316/P2316 TIMERS and TIMER/COUNTERS

Buzzer Output Frequency Generator

The watch timer can generate a steady 2 kHz, 4 kHz, 8 kHz, or 16 kHz signal to the BUZ pin. To select the desired BUZ frequency, load the appropriate value to the WMOD register. This output can then be used to actuate an external buzzer sound. To generate a BUZ signal, three conditions must be met:

—The WMOD.7 register bit is set to "1"

—The output latch for I/O port 2.3 is cleared to "0"

—The port 2.3 output mode flag (PM2) set to “output” mode

Timing Tests in High-Speed Mode

By setting WMOD.1 to "1", the watch timer will function in high-speed mode, generating an interrupt every 3.91 ms. At its normal speed (WMOD.1 = “0”), the watch timer generates an interrupt request every 0.5 seconds. High-speed mode is useful for timing events for program debugging sequences.

Check Subsystem Clock Level Feature

The watch timer can also check the input level of the subsystem clock by testing WMOD.3. If WMOD.3 is "1", the input level at the XTIN pin is high; if WMOD.3 is "0", the input level at the XTIN pin is low.

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