Multimedia Card Registers
18.5.1.23 SD_CAPA Register (offset = 240h) [reset = 0h]
SD_CAPA is shown in
and described in
.
This register lists the capabilities of the MMC/SD/SDIO host controller.
Figure 18-59. SD_CAPA Register
31
30
29
28
27
26
25
24
Reserved
BUS_64BIT
Reserved
VS18
VS30
VS33
R-0h
R/W-0h
R-0h
R/W-0h
R/W-0h
R/W-0h
23
22
21
20
19
18
17
16
SRS
DS
HSS
Reserved
AD2S
Reserved
MBL
R-0h
R-0h
R-0h
R-0h
R-0h
R-0h
R-0h
15
14
13
12
11
10
9
8
Reserved
BCF
R-0h
R-0h
7
6
5
4
3
2
1
0
TCU
Reserved
TCF
R-0h
R-0h
R-0h
LEGEND: R/W = Read/Write; R = Read only; W1toCl = Write 1 to clear bit; -n = value after reset
Table 18-42. SD_CAPA Register Field Descriptions
Bit
Field
Type
Reset
Description
31-29
Reserved
R
0h
28
BUS_64BIT
R/W
0h
64 Bit System Bus Support.
Setting 1 to this bit indicates that the Host Controller supports
64-bit address descriptor mode and is connected to
64-bit address system bus.
0x0(R) = 32-bit System bus address
0x1(R) = 64-bit System bus address
27
Reserved
R
0h
26
VS18
R/W
0h
Voltage support 1.8 V.
Initialization of this register (via a write access to this register)
depends on the system capabilities.
The host driver shall not modify this register after the initialization.
This register is only reinitialized by a hard reset (via mmc_RESET
signal).
0x0(W) = 1.8 V not supported
0x0(R) = 1.8 V not supported
0x1(W) = 1.8 V supported
0x1(R) = 1.8 V supported
25
VS30
R/W
0h
Voltage support 3.0V.
Initialization of this register (via a write access to this register)
depends on the system capabilities.
The host driver shall not modify this register after the initialization.
This register is only reinitialized by a hard reset (via mmc_RESET
signal).
0x0(W) = 3.0 V not supported
0x0(R) = 3.0 V not supported
0x1(W) = 3.0 V supported
0x1(R) = 3.0 V supported
3437
SPRUH73H – October 2011 – Revised April 2013
Multimedia Card (MMC)
Copyright © 2011–2013, Texas Instruments Incorporated