Baseband Signal Processor

FX829

© 1997 Consumer Microcircuits Limited

14

D/829/4

AUDIO ATTENUATION Register (Hex Address $13)

The five least significant bits in this register are used to set the attenuation of the audio volume control

according to the table below:

4

3

2

1

0

Audio Attenuation

0

0

0

0

0

Off

0

0

0

0

1

48.0dB

0

0

0

1

0

46.4dB

0

0

0

1

1

44.8dB

0

0

1

0

0

43.2dB

0

0

1

0

1

41.6dB

0

0

1

1

0

40.0dB

0

0

1

1

1

38.4dB

0

1

0

0

0

36.8dB

0

1

0

0

1

35.2dB

0

1

0

1

0

33.6dB

0

1

0

1

1

32.0dB

0

1

1

0

0

30.4dB

0

1

1

0

1

28.8dB

0

1

1

1

0

27.2dB

0

1

1

1

1

25.6dB

1

0

0

0

0

24.0dB

1

0

0

0

1

22.4dB

1

0

0

1

0

20.8dB

1

0

0

1

1

19.2dB

1

0

1

0

0

17.6dB

1

0

1

0

1

16.0dB

1

0

1

1

0

14.4dB

1

0

1

1

1

12.8dB

1

1

0

0

0

11.2dB

1

1

0

0

1

9.6dB

1

1

0

1

0

8.0dB

1

1

0

1

1

6.4dB

1

1

1

0

0

4.8dB

1

1

1

0

1

3.2dB

1

1

1

1

0

1.6dB

1

1

1

1

1

0dB

Bits 5, 6 and 7 should always be set to "0".

CONTROL 3 / IRQ ENABLE Register (Hex address $40)

This register is a mixture of control bits and interrupt mask bits, as detailed below:

Bit 7

Not used, set to zero.

1200/2400

(Bit 6)

When this bit is "1", the FFSK Rx and Tx are set to operate at 1200 baud.

When this bit it "0", the FFSK Rx and Tx are set to operate at 2400 baud.