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STW5093

Latch output control

Bit DO controls directly logical status of latch output LO: ie, a "ZERO" written in bit DO puts the output LO at

logical 1, while a "ONE" written in bit DO sets the output LO to zero.

Microwire access to B channel on receive path (1)

Bit MR (4) selects access from MICROWIRE Register CR2 to Receive path. When bit MR is set high, data writ-

ten to register CR2 is decoded each frame, sent to the receive path and data input at DR is ignored.

In the other direction, current PCM data input received at DR can be read from register CR2 each frame.

Microwire access to B channel on transmit path (1)

Bit MX (3) selects access from MICROWIRE write only Register CR3 to DX output. When bit MX is set high,

data written to CR3 is output at DX every frame and the output of PCM encoder is ignored.

MSB is always the first PCM bit shifted in or out of: STw5093.

Transmit/Receive enabling/disabling

Bit 'EN' (2) enables or disables voice data transfer on DX and DR pins. When disabled, PCM data from DR is

not decoded and PCM time-slots are high impedance on DX. Default value is disabled.

B-channel selection (1)

Bit TS(1) permits selection between B1 or B2 channels. Default value is B1 channel.

Clock Selection

Bit SLC(0) allows the selection between MCLK and AUXCLK. Default value is MCLK.

CONTROL REGISTER CR2(1)

Data sent to receive path or data received from DR input. Refer to bit MR(4) in "Control Register CR1" para-

graph.

CONTROL REGISTER CR3 (1)

DX data transmitted. Refer to bit MX(3) in "Control Register CR1" paragraph.

CONTROL REGISTER CR4

First byte of a READ or a WRITE instruction to Control Register CR4 is as shown in TABLE 1. Second byte is

as shown in TABLE 6.

(1) Significant in companded mode only

Mu 255 law

True A law even bit

inversion

A law without even bit

inversion

msb

lsb

msb

lsb

msb

lsb

Vin = + full scale

1000

000

01

01010101

1111111

Vin = 0V

1

0

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

0

1

1

1

0

1

1

1

0

1

1

1

0

1

1

1

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Vin = - full scale

0000

000

00

01010100

1111111