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Table 15-11. mmc_resto register, 7 mmc_rdto register, Table 15-12. mmc_rdto register – Intel PXA26X User Manual

Page 539

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Intel® PXA26x Processor Family Developer’s Manual

15-27

MultiMediaCard Controller

15.5.7

MMC_RDTO Register

The MMC_RDTO register determines the length of time that the controller waits after a command
before it turns on the time-out error if data has not been received (see

Table 15-12

). The length of

time before a time-out occurs is measured in increments of 256 20-MHz periods and can be
calculated as follows:

It is the software’s responsibility to calculate the value for READ_TO. The default value is 0xffff,
which corresponds to 838.848 ms.

Table 15-11. MMC_RESTO Register

Physical Address

4110_0014

MMC_RESTO Register

MMC

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

RES_TO

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

1

0

0

0

0

0

0

Bits

Name

Description

31:7

Reserved

6:0

RES_TO

RESPONSE TIME-OUT:

Number of MMC clocks before a response time-out

Time-out Delay

MMC_RDTO[READ_TO]

(

)

256

(

)

×

20MHz

------------------------------------------------------------------------------------------

MMC_RDTO[READ_TO]

(

)

128

(

)

×

10

7

------------------------------------------------------------------------------------------sec

=

=

Table 15-12. MMC_RDTO Register

Physical Address

4110_0018

MMC_RDTO Register

MMC

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_TO

Reset

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

Bits

Name

Description

31:16

Reserved

15:0

READ_TO

READ TIME-OUT:

Specifies the length of time before a data read time-out