![ARTERY AT32F435 Series Reference Manual Download Page 570](http://html1.mh-extra.com/html/artery/at32f435-series/at32f435-series_reference-manual_2977592570.webp)
AT32F435/437
Series Reference Manual
2022.11.11
Page 570
Rev 2.03
25.4.5 SDIO command response register (SDIO_RSPCMD)
The SDIO_RSPCMD register contains the command index of the last command response received. If
the command response transmission does not contain the command index (long or OCR response), the
SDIO_RSPCMD field is unknown, although it should have contained 111111b (the value of the reserved
field from a response)
Bit
Register
Reset value
Type
Description
Bit 31: 6
Reserved
0x0000000
resd
Kept at its default value.
Bit 5: 0
RSPCMD
0x00
ro
Response command index
This field contains the command index of the command
response received.
25.4.6 SDIO response 1..4 register (SDIO_RSPx)
The SDIO_RSPx (x=1..4) register contains the status of a card, which is part of the response received.
Bit
Register
Reset value
Type
Description
Bit 31: 0
CARDSTSx
0x0000 0000 ro
See Table 23-25
The card status size is 32 or 127 bits, depending on the response type.
Table 25-25
Response type and SDIO_RSPx register
Register
Short response
Long response
SDIO_RSP1
Card status [31: 0]
Card status [127: 96]
SDIO_RSP2
Unused
Card status [95: 64]
SDIO_RSP3
Unused
Card status [63: 32]
SDIO_RSP4
Unused
Card status [31: 1]
The most significant bit of the card status is always received first. The least significant bit of the
SDIO_RSP4 register is always 0.
25.4.7 SDIO data timer register (SDIO_DTTMR)
The SDIO_DTTMR register contains the data timeout period in the unit of card bus clock periods. A
counter loads the value from the SDIO_DTTMR register and starts decrementing when the DCSM enters
the Wait_R or busy state. If the counter reaches 0 while the DCSM is in either of these states, a timeout
status flag will be set.
Bit
Register
Reset value
Type
Description
Bit 31: 0
TIMEOUT
0x0000 0000 rw
Data timeout period
Data timeout period in card bus clock cycles.
Note: A data transfer must be written to the SDIO_DTCNTR and the SDIO_DTLEN register before being
written to the SDIO data control register (SDIO_DTCTRL).
25.4.8 SDIO data length register (SDIO_DTLEN)
The SDIO_DTLEN register contains the number of data bytes to be transferred. The value is loaded into
the data counter when data transfer starts.
Bit
Register
Reset value
Type
Description
Bit 31: 25 Reserved
0x00
resd
Kept at its default value.
Bit 24: 0
DTLEN
0x0000000
rw
Data length value
Number of data bytes to be transferred.
Note: For a block data transfer, the value in the SDIO_DTLEN must be a multiple of the block data size.
A data transfer must be written to the SDIO_DTCNTR and the SDIO_DTLEN register before being
written to the SDIO data control register (SDIO_DTCTRL).