16 modem data register (modr), Misr bit definitions -31, Modr bit definitions -31 – Intel PXA255 User Manual

Page 481: Table 13-21

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Intel® PXA255 Processor Developer’s Manual

13-31

AC’97 Controller Unit

13.8.3.16

Modem Data Register (MODR)

This is a read/write register. Ignore reads from reserved bits. Write zeros to reserved bits.

A 32-bit sample write to this register updates the data into the Modem Transmit FIFO. A read to
this register gets a 32-bit sample from the Modem Receive FIFO.

Table 13-21. MISR Bit Definitions

Physical Address

4050_0118

MISR Register

AC’97 Controller Unit

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

FI

FO

E

re

s

e

rved

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

0

Bits

Name

Description

31:5

reserved

4

FIFOE

FIFO error (FIFOE)

0 = No Receive FIFO error has occurred.
1 = A receive FIFO error occurred. This bit is set if a receive FIFO overrun occurs. In this

case, the FIFO pointers don't increment, the incoming data from the AC-link is not
written into the FIFO and will be lost. This could happen due to DMA controller having
excessive bandwidth requirements and hence not being able to flush out the Receive
FIFO in time.

Bit is cleared by writing a 1 to this bit position.

3:0

reserved

Table 13-22. MODR Bit Definitions

Physical Address

4050_0140

MODR Register

AC’97 Controller Unit

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

MODEM_DAT

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

0

Bits

Name

Description

31:16

reserved

15:0

MODEM_DAT Modem data

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