Integrated Circuits Inc.

aP8821

4

Output Selections

There are three independent output pins OUT1, OUT2 and OUT3, available for four combinations of

LED1, LED2, STOP and BUSY signals for each voice group.

OUT1

OUT2

OUT3

1.

LED2

LED1

BUSY

2.

STOP

LED1

LED2

3.

LED1

BUSY

STOP

4.

LED1

BUSY

/BUSY

LED1 and LED2 are complemented outputs flashing at a fix interval. STOP pulse gives a long

enough positive pulse at the end of the playback for each group with option to enable or disable it.

BUSY is active high depends on voice Block setting. That means BUSY signal can be set to high

when some voice Blocks are being played but set to low for the others.

Software Support

All those Options and Output selections can be set with a dedicated OTP compiler and programmer

software supplied by APLUS.

Key trigger mode and CPU trigger mode

In Key trigger mode, S1 to S4 will trigger four voice groups. The rest of the voice groups can only be

triggered by SBT sequential trigger pin.

In CPU trigger mode, binary data is input to S4~S1. A high pulse is input to SBT pin with pulse

width equal to or longer than the debounce time to strobe the data to initial the playblack. Data

patterns “1110” and “1111” is not allowed.

Group-n

S4

S3

S2

S1

Group-n

S4

S3

S2

S1

Group1

0

0

0

0

Group9

1

0

0

0

Group2

0

0

0

1

Group10

1

0

0

1

Group3

0

0

1

0

Group11

1

0

1

0

Group4

0

0

1

1

Group12

1

0

1

1

Group5

0

1

0

0

Group13

1

1

0

0

Group6

0

1

0

1

Group14

1

1

0

1

Group7

0

1

1

0

X

1

1

1

0

Group8

0

1

1

1

X

1

1

1

1