Information

Enhanced Secure Digital Host Controller
MPC8308 PowerQUICC II Pro Processor Reference Manual, Rev. 1
11-64 Freescale Semiconductor
NOTE
• CMD3 differs for MMC and SD cards
For MMCs, CMD3 is referred to as SET_RELATIVE_ADDR and has a
response type R1
For SD cards, CMD3 is referred to as SEND_RELATIVE_ADDR and
has a response type R6, with RCA inside
• CMD6 differs completely between high-speed MMCs and high-speed
SD cards. Command SWITCH_FUNC is used for high speed SD cards.
• Command SWITCH is for high-speed MMCs. The index field can
contain any value from 0–255, but only values 0–191 are valid. If the
index value is in the 192–255 range, the card does not perform any
modification and the status bit EXT_CSD[SWITCH_ERROR] is set.
The access bits are shown in Table 11-27:
ACMD22 adtc [31–0] stuff bits R1 SEND_NUM_WR_
SECTORS
Send the number of the written
(without errors) sectors. Responds
with 32 bit + CRC data block.
ACMD23 ac [31–23] stuff bits
[22–0] number of
blocks
R1 SET_WR_BLK_ERASE_
COUNT
—
ACMD41 bcr [31–0] OCR R3 SD_APP_OP_COND Asks the accessed card to send its
operating condition register (OCR)
content in the response on the
SD_CMD line.
ACMD42 ac — R1 SET_CLR_CARD_DETECT —
ACMD51 adtc [31–0] stuff bits R1 SEND_SCR Reads the SD Configuration Register
(SCR)
1
Registers mentioned in this table are SD card registers.
Table 11-27. EXT_CSD Access Modes
Bits Access Name Operation
00 Command set The command set is changed according to the command set field of the argument
01 Set bits The bits in the pointed byte are set, according to the set bits in the value field.
10 Clear bits The bits in the pointed byte are cleared, according to the set bits in the value field.
11 Write byte The value field is written into the pointed byte.
Table 11-26. Commands for MMC/SD/SDIO (continued)
CMD
INDEX
Type Argument Resp Abbreviation Description
1