Datasheet

AT89C5132

4173C–USB–07/04

Figure 44. Voice or Sound Mode Audio Flows

Note: 1. An under-run occurrence signifies that the C51 core did not respond to the previous sample request interrupt. It may never

occur for a correct voice/sound generation. It is the user’s responsibility to mask it or not.

Select Audio

SRC = 1

Voice/Song Mode

Configuration

Configure Interface

HLR = X

DSIZ = X

POL = X

JUST4:0 = XXXXXb

DUP1:0 = XX

Program Audio Clock

Enable DAC System

Clock

AUDEN = 1

Wait for DAC

Enable Time

Load 8 Samples in the

Audio Buffer

Enable Interrupt

Set MSREQ & MUDRN

EAUD = 1

Audio Interrupt

Service Routine

Under-run Condition

Load 4 Samples in the

Audio Buffer

Sample Request?

SREQ = 1?