16 mmc_res fifo, 17 mmc_rxfifo fifo, 16 mmc_res fifo -36 15.5.17 mmc_rxfifo fifo -36 – Intel PXA255 User Manual

Page 538: Mmc_res, fifo entry -36, Mmc_rxfifo, fifo entry -36

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15-36

Intel® PXA255 Processor Developer’s Manual

MultiMediaCard Controller

15.5.16

MMC_RES FIFO

MMC_RES FIFO, shown in

Table 15-21

, contains the response after a command. It is 16 bits wide

by eight entries.The RES FIFO does not contain the 7-bit CRC for the response. The status for
CRC checking and response time-out status is in the status register, MMC_STAT.

The first half-word read from the response FIFO is the most significant half-word of the received
response.

This is a read-only register. Ignore reads from reserved bits.

15.5.17

MMC_RXFIFO FIFO

MMC_RXFIFO, shown in

Table 15-22

, consists of two dual FIFOs, where each FIFO is eight bits

wide by 32 entries deep. This FIFO holds the data read from a card. It is a read only FIFO to the
software, and is read on 8-bit boundaries. The eight bits of data are read on a 32-bit boundary and
occupying the least significant byte lane (7:0).

This is a read-only register. Ignore reads from reserved bits.

Table 15-21. MMC_RES, FIFO Entry

Physical Address

0x4110_003c

MMC_RES FIFO Entry

MultiMediaCard 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

RESPONSE_DATA

Reset

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

Bits

Name

Description

31:16

reserved

15:0

RESPONSE_

DATA

Two bytes of response data

Table 15-22. MMC_RXFIFO, FIFO Entry

Physical Address

0x4110_0040

MMC_RXFIFO Entry

MultiMediaCard 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

READ_DATA

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

x

x

x

x

x

x

x

x

Bits

Name

Description

31:8

reserved

7:0

READ_DATA One byte of read data

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