Integrated Circuits Inc.

aP89341/170/085

Ver 3.1

4

Oct 09, 2008

VOICE SECTION COMBINATIONS

Voice files created by the PC base developing system are stored in the built-in EPROM of the

aP89341/170/085 chip as a number of fixed length Voice Blocks. Voice Blocks are then selected and

grouped into Voice Groups for playback. Up to 254 Voice Groups are allowed. A Voice Block Table

is used to store the information of combinations of Voice Blocks and then group them together to form

Voice Group.

Chip

aP89341

aP89170

aP89085

Memory size

8M bits

4M bits

2M bits

Max no. of Voice Block

2016

992

480

Max. no. of Voice Group

254

254

254

No of Voice Table entries

7680

7680

7680

Voice Length

(@ 6KHz 4-bit ADPCM)

341 sec

170 sec

85 sec

Example of Voice Block Combination

Assume here we have three voice files, they are “How are You?”, Sound Effect and Music. Each of

the voice file is divided into a number of fixed length Voice Block and stored into the memory.

Voice File 1 - “How are You?” is stored in Voice Block B0 to B12.

Voice File 2 - Sound Effect is stored in Voice Block B13 to B15.

Voice File 3 - Music is Voice Block B16 to B40.

Voice Blocks are grouped together using Voice Table to form Voice Group for playback:

Group no.

Voice Group contents

Voice Table Entries

Group 1

“How are You?”

B0 … B12

Group 2

Sound Effect + “How are You?”

B13 … B15 + B0 … B12

Group 3

“How are You?” + Music

B0 … B12 + B16 … B40

Group 4

Music

B16 … B40

Voice Data Compression

Voice File data is stored in the on-chip EPROM as either 4-bit ADPCM or 8-bit PCM format. Voice

data stored as 4-bit ADPCM provides 2:1 data compression which can save 50% of memory space.

On the other hand, voice data are stored as 8-bit PCM format means no data compression is employed

but voice playback quality will be better.