====== eMMC Commands ======

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===== Command Table =====

<datatables>
^ Command  ^ Data Line  ^ Response  ^ Description                                                                                                                                                                       ^ Version  ^ Addend                                ^
| CMD1     | -          | R3        | Ask device to send its <wrap reg>OCR</wrap>.                                                                                                                                      |          |                                       |
| CMD6     | b          | R1b       | Switches the mode of operation of the selected Device or modifies the <wrap reg>EXT_CSD</wrap> registers                                                                          |          | [[#cmd6|{{mdi>note-text}}]]           |
| CMD9     | -          | R2        | Obtain <wrap reg>CSD</wrap> on the CMD line.                                                                                                                                      |          |                                       |
| CMD7     | -          | R1/R1b    | Command toggles a device between the <wrap state>standby</wrap> and <wrap state>transfer</wrap> or between the <wrap state>programming</wrap> and <wrap state>disconnect</wrap>.  |          |                                       |
| CMD13    | -          | R1        | Addressed card sends its status register.                                                                                                                                         |          |                                       |
| CMD8     | R          | R1        | Device sends its <wrap reg>EXT_CSD</wrap> register as a block of data                                                                                                             |          |                                       |
| CMD18    | R          | R1        | Read multiple blocks.                                                                                                                                                             |          | [[#multiple-xfer|{{mdi>note-text}}]]  |
| CMD17    | R          | R1        | Read single bolck.                                                                                                                                                                |          |                                       |
| CMD24    | R          | R1        | Write single block.                                                                                                                                                               |          |                                       |
| CMD25    | R          | R1        | Write multiple blocks.                                                                                                                                                            |          | [[#multiple-xfer|{{mdi>note-text}}]]  |

</datatables>
==== CMD6 ====
  * Unlike SD, eMMC cards don't have a configuration register to notify supported __bus width__. 
  * The __speed mode__ supported by the card can be determined by the __''DEVICE_TYPE'' (196th byte) of <wrap reg>EXT_CSD</wrap>__.
  
<wrap #multiple-xfer />
==== Multiple Block Xfer Command ====
The following commands will __continuously__ write/read blocks of data until a __STOP_TRANSMISSION__ (''CMD12'') follows or the __requested number of block (Specified by ''CMD23'')__ received.
  * ''CMD18'' - Read multiple blocks.
  * ''CMD25'' - Write multiple blocks.