Acrosser AR-B1320 - Manual (Page 17)

A A R R - - B B 1 1 3 3 2 2 0 0 U U s s e e r r ’ ’ s s G G u u i i d d e e
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.