Data Transfer Commands - Altera Cyclone V Device Handbook

cv_54011
2013.12.30
Parameter
card_number
cmd_index
send_initialization
stop_abort_cmd
response_length
response_expect
wait_prvdata_complete
check_response_crc

Data Transfer Commands

Data transfer commands transfer data between the memory card and the controller. To issue a data command,
the controller requires a command argument, total data size, and block size. Data transferred to or from the
memory card is buffered by the controller FIFO buffer.
Confirming Transfer State
Before issuing a data transfer command, software must confirm that the card is not busy and is in a transfer
state, by performing the following steps:
1. Issue an SD/SDIO SEND_STATUS (CMD13) command. The controller sends the status of the card as
the response to the command.
2. Check the card's busy status.
SD/MMC Controller
Send Feedback
Value
1 For one card
Command Set this parameter to the command number. For
Index example, set to 8 for the SD/SDIO SEND_IF_COND
(CMD8) command.
0 or 1 1 for card reset commands such as the SD/SDIO
GO_IDLE_STATE command
0 otherwise
0 or 1 1 for a command to stop data transfer, such as the
SD/SDIO STOP_TRANSMISSION command
0 otherwise
0 or 1 1 for R2 (long) response
0 for short response
0 or 1 0 for commands with no response, such as SD/SDIO
GO_IDLE_STATE, SET_DSR (CMD4), or GO_
INACTIVE_STATE (CMD15).
1 otherwise
User Selectable
1 Before sending a command on the command line,
the host must wait for completion of any data
command already in process. Altera recommends
that you set this bit to 1, unless the current
command is to query status or stop data transfer
when transfer is in progress.
1 or 0 1 if the response includes a valid CRC, and the
software is required to crosscheck the response CRC
bits.
0 otherwise
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Data Transfer Commands
Comment
Altera Corporation
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