SNC745
16-bit Voice Processor
IREN
P0.15
I/O Pad
Overflow
Timer2
2
P0.15 Modulated with a carry signal
8. TIMER/COUNTER
SNC745 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.
TnC (8-bit)
Enable
If equal, Time out
(system clock)/2*
8-bit Up
Counter
comparator
clear
Pre-scalar
Auto-reload
9. DAC & PWM
To play out voices, SNC745 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 SNC745. 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.
6
Ver. 1.3
October 23, 2002
SONIX [ SONIX TECHNOLOGY COMPANY ]
