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Timer -9, 9 timer – Acrosser AR-B1320 User Manual

Page 17

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2-9

2.9 TIMER

The AR-B1320 provides three programmable timers, each with a timing frequency of 1.19 MHz.

Timer 0 The output of this timer is tied to interrupt request 0. (IRQ 0)
Timer 1 This timer is used to trigger memory refresh cycles.
Timer 2 This timer provides the speaker tone.

Application programs can load different counts into this timer to
generate various sound frequencies.