Atmel Xplained Evaluation Board AT32UC3A3-XPLD AT32UC3A3-XPLD 데이터 시트
제품 코드
AT32UC3A3-XPLD
829
32072H–AVR32–10/2012
AT32UC3A3
Figure 31-9. Command/Response Functional Flow Diagram
Note:
1. If the command is SEND_OP_COND, the CRC error bit is always present (refer to R3
response in the MultiMedia Card specification).
31.6.3
Data Transfer Operation
The MultiMedia Card allows several read/write operations (single block, multiple blocks, stream,
etc.). These kind of transfers can be selected setting the Transfer Type field in the CMDR regis-
ter (CMDR.TRTYP).
etc.). These kind of transfers can be selected setting the Transfer Type field in the CMDR regis-
ter (CMDR.TRTYP).
These operations can be done using the features of the DMA Controller.
In all cases, the Data Block Length must be defined either in the Data Block Length field in the
MR register (MR.BLKLEN)), or in the Block Register (BLKR). This field determines the size of
the data block.
MR register (MR.BLKLEN)), or in the Block Register (BLKR). This field determines the size of
the data block.
Set the command argument
ARGR = Argument
(1)
Set the command
CMD = Command
Read the SR register
0
Yes
1
SR.CMDRDY
Wait for SR.CMDRY bit set
to one
Check error bits in the
SR register
(1)
Status error bits?
RETURN OK
RETURN ERROR
(1)
Read response if required