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4 serial audio clock divider register (sadiv), 4 serial audio clock divider register (sadiv) -12, Sasr0 bit definitions -12 – Intel PXA255 User Manual

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14-12

Intel® PXA255 Processor Developer’s Manual

Inter-Integrated-Circuit Sound (I2S) Controller

14.6.4

Serial Audio Clock Divider Register (SADIV)

SADIV, shown in

Table 14-8

, is used for generating six different BITCLK frequencies and hence

six different sampling frequencies.

Table 14-7. SASR0 Bit Definitions

Physical Address

0x4040_000C

Serial Audio Controller I

2

S/MSB-

Justified Status Register

I

2

S Controller

Bit

31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9

8 7

6 5

4 3

2 1

0

reserved

RFL

TFL

re

se

rv

e

d

RO

R

TU

R

RF

S

TFS

BSY

RN

E

TN

F

Reset 0

0

0 0

0 0

0 0

0

0 0

0 0

0 0

0

0 0

0 0

0 0

0

0 0

0 0

0 0

0 0

1

Bits

Name

Description

31:16

reserved

15:12

RFL

Receive FIFO Level: number of entries in Receive FIFO

11:8

TFL

Transmit FIFO Level: number of entries in Transmit FIFO

7

reserved

6

ROR

Receive FIFO Overrun:
0 = Receive FIFO has not experienced an overrun

1 = I

2

S

attempted data write to full Receive FIFO (Interruptible)

Can interrupt processor if bit6 of Serial Audio Interrupt Mask Register is set.
Cleared by setting bit 6 of Serial Audio Interrupt Clear Register.

5

TUR

Transmit FIFO Under-run:
0 = Transmit FIFO has not experienced an under-run

1 = I

2

S

attempted data read from an empty Transmit FIFO

Can interrupt processor if bit 5 of Serial Audio Interrupt Mask Register is set.
Cleared by setting bit 5 of Serial Audio Interrupt Clear Register.

4

RFS

Receive FIFO Service Request:
0 = Receive FIFO level below RFL threshold, or I

2

S

disabled

1 = Receive FIFO level is at or above RFL threshold.
Can interrupt processor if bit 4 of Serial Audio Interrupt Mask Register is set.
Cleared automatically when # of Receive FIFO entries < (RFTH + 1).

3

TFS

Transmit FIFO Service Request:
0 = Transmit FIFO level exceeds TFL threshold, or I

2

S

disabled

1 = Transmit FIFO level is at or below TFL threshold
Can interrupt processor if bit 3 of Serial Audio Interrupt Mask Register is set.
Cleared automatically when # of Transmit FIFO entries >= (TFTH + 1).

2

BSY

I

2

S

Busy:

0 = I

2

S

is idle or disabled

1 = I

2

S

currently transmitting or receiving a frame

1

RNE

Receive FIFO not empty:
0 = Receive FIFO is empty

1 = Receive FIFO is not empty

0

TNF

Transmit FIFO not full:
0 = Transmit FIFO is full
1 = Transmit FIFO is not full