Samsung S3P80C5, User Manual

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S3P80C5/C80C5/C80C8 BASIC TIMER AND TIMER 0
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BASIC TIMER and TIMER 0
MODULE OVERVIEW
The S3P80C5/C80C5/C80C8 has two default timers: an 8-bit basic timer and one 8-bit general-purpose
timer/counter. The 8-bit timer/counter is called timer 0.
Basic Timer (BT)
You can use the basic timer (BT) in two different ways:
— As a watchdog timer to provide an automatic reset mechanism in the event of a system malfunction, or
— To signal the end of the required oscillation stabilization interval after a reset or a Stop mode release.
BASIC TIMER CONTROL REGISTER (BTCON)
The basic timer control register, BTCON, is used to select the input clock frequency, to clear the basic timer
counter and frequency dividers, and to enable or disable the watchdog timer function. It is located in set 1,
address D3H, and is read/write addressable using Register addressing mode.
A system reset clears BTCON. This enables the watchdog function and selects a basic timer clock frequency of
f
OSC
/4096. To disable the watchdog function, you must write the signature code '1010B' to the basic timer
register control bits BTCON.7–BTCON.4. For more reliability, we recommend to use the Watch-dog timer
function in remote controller and hand-held product application.