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GD32F20x User Manual
673
Bits
Fields
Descriptions
31:12
Reserved
Must be kept at reset value
11
IOEN
SD I/O specific function enable(SD I/O only)
0: Not SD I/O specific function
1: SD I/O specific function
10
RWTYPE
Read wait type(SD I/O only)
0: Read Wait control using SDIO_DAT[2]
1: Read Wait control by stopping SDIO_CLK
9
RWSTOP
Read wait stop(SD I/O only)
0: No effect
1: Stop the read wait process if RWEN bit is set
8
RWEN
Read wait mode enabled(SD I/O only)
0: Read wait mode is disabled
1: Read wait mode is enabled
7:4
BLKSZ[3:0]
Data block size
These bits defined the block size when data transfer is block transfer.
0000: block size = 2
0
= 1 byte
0001: block size = 2
1
= 2 bytes
0010: block size = 2
2
= 4 bytes
0011: block size = 2
3
= 8 bytes
0100: block size = 2
4
= 16 bytes
0101: block size = 2
5
= 32 bytes
0110: block size = 2
6
= 64 bytes
0111: block size = 2
7
= 128 bytes
1000: block size = 2
8
= 256 bytes
1001: block size = 2
9
= 512 bytes
1010: block size = 2
10
= 1024 bytes
1011: block size = 2
11
= 2048 bytes
1100: block size = 2
12
= 4096 bytes
1101: block size = 2
13
= 8192 bytes
1110: block size = 2
14
= 16384 bytes
1111: reserved
3
DMAEN
DMA enable bit
0: DMA is disabled.
1: DMA is enabled.
2
TRANSMOD
Data transfer mode
0: Block transfer
1: Stream transfer or SDIO multibyte transfer
1
DATADIR
Data transfer direction
0: Write data to card.
Summary of Contents for GD32F20 Series
Page 191: ...GD32F20x User Manual 191 Bits Fields Descriptions 31 0 TRNDATA 31 0 32 Bit Random data ...
Page 290: ...GD32F20x User Manual 290 conversion is ongoing ...
Page 325: ...GD32F20x User Manual 325 15 0 ALRM 15 0 RTC alarm value low ...
Page 385: ...GD32F20x User Manual 385 ...
Page 523: ...GD32F20x User Manual 523 clears AERR bit by writing 0 to it ...