APPOTECH CW6632B - SDC Operation Guide; 0 6 B C Ommand Operation

12 SD Card Host Controller (SDC) 97
CW6632B Bluetooth 3.0 Audio Player SOC Version 1.0.0
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Access
WO
WO
WO
WO
WO
WO
WO
WO
SDBAUD: Baud rate control
Baud rate = system clock / 2*(SDBAUD +1)
Register 12-5 SDCPTR – SD host Command DMA address
Position
7
6
5
4
3
2
1
0
Name
CPTR
Default
0
0
0
0
0
0
0
0
Access
WO
WO
WO
WO
WO
WO
WO
WO
Register 12-6 SDDPTR – SD host Data DMA address
Position
7
6
5
4
3
2
1
0
Name
DPTR
Default
0
0
0
0
0
0
0
0
Access
WO
WO
WO
WO
WO
WO
WO
WO
Register 12-7 SDDCNT – SD host Data Counter
Position
7
6
5
4
3
2
1
0
Name
DCNT
Default
0
0
0
0
0
0
0
0
Access
WO
WO
WO
WO
WO
WO
WO
WO
In order to get the correct DATA DMA counter, you should write this register twice. First write the higher byte, then
the low byte. The range is: 0x00~0x1ff.
Total number of bytes received / transferred is (DCNT + 1) x 2
12.4 SDC Operation Guide
12.4.1 206Bcommand Operation
When command is kick-started (by writing one of the following kick-start command to SDCFG[7：5]), SD module
sends out the pre-set command. After command has been sent, it will kick-start in one of the following options:
001 = Wait for 6-byte response. CPND is set to „1‟ by hardware after response is received.
011 = Wait for 17-byte response. CPND is set to „1‟ by hardware after response is received.
101 = Wait for 6-byte response. After response is received and DAT0 is „1‟, CPND is set to „1‟ by hardware.
111 = Wait for 17-byte response. After response is received and DAT0 is „1‟, CPND is set to „1‟ by hardware.
010 = Do not wait for response and set CPND to „1‟ by hardware immediately.
100 = Do not wait for response, if DAT0 is „1‟, set CPND to „1‟ by hardware immediately.
CPND (SDCFG [13]) will be set to 1 by hardware and it indicates that command and response operations are
complete. At this moment, if RCRCE (SDCFG2 [7]) is set to 1, the received response has CRC error. The previous
command should be resent.
Note: RCRCE bit is valid only when receiving R1 or R1b response. RCRCE bit can be ignored for other types of