15-28
Intel® PXA255 Processor
Developer’s Manual
MultiMediaCard Controller
15.5.7
MMC_RDTO Register (MMC_RDTO)
MMC_RDTO, shown in
Table 15-11
, 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. 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.
This is a read/write register. Ignore reads from reserved bits. Write zeros to reserved bits.
Time-out Delay
MMC_RDTO[READ_TO]
(
)
256
(
)
×
20
MHz
------------------------------------------------------------------------------------------
MMC_RDTO[READ_TO]
(
)
128
(
)
×
10
7
------------------------------------------------------------------------------------------sec
=
=
Table 15-11. MMC_RDTO Register
Physical Address
0x4110_0018
MMC_RDTO Register
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_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
Specifies the length of time before a data read time-out
Summary of Contents for PXA255
Page 1: ...Intel PXA255 Processor Developer s Manual January 2004 Order Number 278693 002 ...
Page 24: ...xxiv Intel PXA255 Processor Developer s Manual Contents ...
Page 30: ...1 6 Intel PXA255 Processor Developer s Manual Introduction ...
Page 310: ...7 46 Intel PXA255 Processor Developer s Manual LCD Controller ...
Page 330: ...8 20 Intel PXA255 Processor Developer s Manual Synchronous Serial Port Controller ...
Page 358: ...9 28 Intel PXA255 Processor Developer s Manual I2 C Bus Interface Unit ...
Page 488: ...13 36 Intel PXA255 Processor Developer s Manual AC 97 Controller Unit ...
Page 572: ...16 30 Intel PXA255 Processor Developer s Manual Network SSP Serial Port ...
Page 599: ...Intel PXA255 Processor Developer s Manual 17 27 Hardware UART ...
Page 600: ......