KS57C2308/P2308/C2316/P2316 TIMERS and TIMER/COUNTERS
11-23
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.