For more information about packed commands, refer to JEDEC Standard No. 84-A441, available on the
JEDEC website.
Related Information
For more information about packed commands, refer to JEDEC Standard No. 84-A441, available on the
JEDEC website.
Transfer Stop and Abort Commands
This section describes stop and abort commands. The SD/SDIO STOP_TRANSMISSION command can
terminate a data transfer between a memory card and the controller. The ABORT command can terminate
an I/O data transfer for only an SDIO card.
†
STOP_TRANSMISSION (CMD12)
The host can send the STOP_TRANSMISSION (CMD12) command on the CMD pin at any time while a
data transfer is in progress. Perform the following steps to send the STOP_TRANSMISSION command to
the SD/SDIO card device:
†
1. Set the
wait_prvdata_complete
bit of the
cmd
register to 0.
†
2. Set the
stop_abort_cmd
in the
cmd
register to 1, which ensures that the CIU stops.
†
The STOP_TRANSMISSION command is a non-data transfer command. For more information, refer to
Non-Data Transfer Commands
.
†
Related Information
on page 11-35
Refer to this section for information on the STOP_TRANSMISSION command.
ABORT
The ABORT command can only be used with SDIO cards. To abort the function that is transferring data,
program the ABORT function number in the ASx[2:0] bits at address 0x06 of the card common control
register (CCCR) in the card device, using the IO_RW_DIRECT (CMD52) command. The CCCR is located
at the base of the card space 0x00 – 0xFF.
†
The ABORT command is a non-data transfer command. For more information, refer to
Non-Data Transfer
Commands
.
†
Related Information
on page 11-35
Refer to this section for information on the ABORT command.
Sending the ABORT Command
Perform the following steps to send the ABORT command to the SDIO card device:
†
1. Set the
cmdarg
register to include the appropriate command argument parameters listed in
cmdarg
Register Settings for SD/SDIO ABORT Command
.
†
2. Send the IO_RW_DIRECT command by setting the following fields of the
cmd
register:
†
SD/MMC Controller
Altera Corporation
cv_54011
Transfer Stop and Abort Commands
11-44
2013.12.30