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SD/SDIO/MMC card host interface (SDMMC)
Bit 8 WAITINT: CPSM waits for interrupt request
Bits 7:6 WAITRESP: Wait for response bits
Bits 5:0 CMDINDEX: Command index
The command index is sent to the card as part of a command message.
Note:
1
After a data write, data cannot be written to this register for three SDMMCCLK clock periods
plus two PCLK2 clock periods.
2
MultiMediaCards can send two kinds of response: short responses, 48 bits long, or long
responses,136 bits long. SD card and SD I/O card can send only short responses, the
argument can vary according to the type of response: the software will distinguish the type
of response according to the sent command.
41.8.5
SDMMC command response register (SDMMC_RESPCMD)
Address offset: 0x10
Reset value: 0x0000 0000
The SDMMC_RESPCMD register contains the command index field of the last command
response received. If the command response transmission does not contain the command
index field (long or OCR response), the RESPCMD field is unknown, although it must
contain 111111b (the value of the reserved field from the response).
31
30
29
Res.
Res.
Res.
Res.
15
14
13
Res.
Res.
Res.
Res.
Bits 31:6 Reserved, must be kept at reset value.
Bits 5:0 RESPCMD: Response command index
Read-only bit field. Contains the command index of the last command response received.
41.8.6
SDMMC response 1..4 register (SDMMC_RESPx)
Address offset: (0x10 + (4 × x)); x = 1..4
Reset value: 0x0000 0000
The SDMMC_RESP1/2/3/4 registers contain the status of a card, which is part of the
received response.
1438/1693
If this bit is set, the CPSM disables command timeout and waits for an interrupt request.
They are used to configure whether the CPSM is to wait for a response, and if yes, which
kind of response.
00: No response, expect CMDSENT flag
01: Short response, expect CMDREND or CCRCFAIL flag
10: No response, expect CMDSENT flag
11: Long response, expect CMDREND or CCRCFAIL flag
28
27
26
25
Res.
Res.
Res.
12
11
10
9
Res.
Res.
Res.
24
23
22
Res.
Res.
Res.
8
7
6
Res.
Res.
Res.
DocID024597 Rev 3
21
20
19
18
Res.
Res.
Res.
Res.
5
4
3
2
RESPCMD
r
r
r
r
RM0351
17
16
Res.
Res.
1
0
r
r
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