SNC725

16-bit Voice Processor

Ver:1.2

October 23, 2002

6

P0.15 Modulated with a carry signal

8. TIMER/COUNTER

SNC725 provides three 8 -bit timer/event counters (T0/T1/T2). Each timer is 8-bit binary

up-count timer with pre-scalar and auto-reload function. Timer 0 (T0) is used when voice

playing, so user should avoid to use T0.

9. DAC & PWM

To play out voices, SNC725 contains two different solutions, DAC and PWM, for the

users’ applications. The user can choose one of these two solutions in his design. Only

one function can be activated at one time.

DAC: A 10-bit current type digital-to-analog converter is built-in SNC725. The

relationship between input digital data and output analog current is listed in the following

table. Also, the recommended application circuit is illustrated as follows.

Timer2

Overflow

P0.15

2

IREN

I/O Pad

Auto-reload

TnC (8-bit)

(system clock)/2*

Pre-scalar

Enable

8-bit Up

Counter

If equal, Time out

/2

/4

/8

/256

MU

comparator

clear