====== eMMC Module ======

<WRAP left round important 60%>

  * Check the eMMC module compatibility.
  * If your eMMC is corrupted or have a wrong boot loader, reinstall the proper boot loader in the eMMC via [[emmc_recovery|eMMC Recovery]].
  * <color #ed1c24>**The Black eMMC modules work with only ODROID-C0/C1/C1+/C2**</color>. Other Blue/Red eMMC modules work with all ODROID boards.

</WRAP>



====== How to distinguish the Sandisk eMMC ver 5.1 from the 5.0 ======
The eMMCs from Sandisk will be version up to 5.1 with faster data transfer speed starting from 20th of July 2017.  

As shown in the figure below, the QR code is on the left side of the ver5.1 chipset while eMMC ver 5.0 has it on the right side.

|  **eMMC 5.0  **                                        |  **eMMC 5.1**  |
| {{:en:odroid-xu3_4:sandisk_emmc_v5.0.png?150&direct}}  | {{ :en:odroid-xu3_4:sandisk_emmc_v5.1.png?150&direct }}  |




====== eMMC modules for current running products 2016~ ======
{{:en:emmcreference2.jpg?350|}}



====== eMMC modules for old products ======
{{:en:others:emmc_ref_chart.png?600}}

Note: XU4 and XU3 have software compatibility each other.
===== Reference =====
=== eMMC Module & eMMC Reader Schematics ===

[[http://forum.odroid.com/download/file.php?id=433|Download eMMC module schematics]]\\
[[http://forum.odroid.com/download/file.php?id=1036&mode=view|eMMC reader board schematics]]\\
eMMC board dimensions : 18.5mm x 13.5mm\\
Gap between the PCBs : 1.1mm (Height of assembled B2B connectors\\

=== eMMC connector specification ===

The connector is made by LS-Mtron Korea.\\
On the eMMC module, we've used the GB042-34S-H10 (Socket-34pin). \\
On the host board, we've used the GB042-34P-H10 (Plug-34pin). \\

[[http://www.lsmtron.com/pdf/Connector&Antenna_catalog.PDF|The connector specification is here]]


=== Information about Sandisk eMMC (iDisk Extreme) ===
[[http://www.sandisk.com/products/embedded/inand/inand-extreme]]

=== Information about Samsung eMMC ===
[[http://www.samsung.com/semiconductor/products/flash-storage/emmc/]]

=== Information about Essencore eMMC (8GB eMMC is used for XU4) ===
[[http://www.the-aio.com/emmcfeature]]

=== Information about Toshiba eMMC ===
[[https://toshiba.semicon-storage.com/us/product/memory/nand-flash/mlc-nand/emmc.html]]


===== eMMC Read/Write test on ODROID-C2 HS400 mode =====
Unit : MByte/sec
|       |         |  Samsung  |  Toshiba  |  Sandisk  |
|   8G  |  Write  |    45.4   |    21.9   |    N/A    |
|   8G  |  Read   |    113    |    148    |    N/A    |
|  16G  |  Write  |    80.1   |    N/A    |    25.6   |
|  16G  |  Read   |    126    |    N/A    |    153    |
|  32G  |  Write  |    124    |    N/A    |    98.7   |
|  32G  |  Read   |    125    |    N/A    |    153    |
|  64G  |  Write  |    124    |    83.7   |    107    |
|  64G  |  Read   |    124    |    153    |    153    |

Note 1: Write/Read command for the eMMC benchmark.\\
$ dd if=/dev/zero of=test.tmp oflag=direct bs=1M count=1024 \\
$ dd if=test.tmp of=/dev/null iflag=direct bs=1M \\

Note 2: \\
Black eMMC module is made with Samsung eMMC chipset.\\
Red/Blue(normal) eMMC module is made with Sandisk or Toshiba or AIO chipset.\\
C1/C0/C1+/C2 works with Black and Red eMMC modules.\\
<color #ed1c24>**XU4/XU3/U3/X2/U2 do NOT work with Black eMMC module.**</color>\\

===== New 8GB eMMC test on XU4 Ubuntu =====

New 8GB eMMC Red PCB for XU4 model is based on AIO's eMMC 5.0 technology. \\

Sequential speed with "dd" test \\
dd write : 15.1 MB/s \\
dd read : 104 MB/s \\

Random access(IOPS) speed test with 4k block.\\
Random write : io=993228KB, bw=9928.2KB/s, iops=2482 \\
Random read : io=1479.1MB, bw=15149KB/s, iops=3787 \\


===== eMMC vs SD card performance comparison on C2 Android =====

16GB eMMC Black PCB\\
16GB UHS-1 SDHC Card (Sandisk SDSDQAD-016G UHS-I 50 OEM model)

Cleanly flashed Android 5.1 V2.8 image and installed GApps Pico package.\\
eMMC booting time from power on event : 18~20 seconds \\
SDHC booting time from power on event : 32~35 seconds \\


===== Check points for system software developers =====

* Do not overwrite the hidden eMMC boot partition.  If you have, go here to recover: [[en:emmc_recovery|How to recover the eMMC boot loader.]] \\

* eMMC must be partitioned like so; \\
---FAT16 partition with UUID 6E35-5356 (boot)\\
---EXT4 partition with UUID e139ce78-9841-40fe-8823-96a304a09859 (linux)\\

* Copy contents from Ubuntu image partitions to the boot and linux partitions using "cp -afpv source destination"\\

* Insert eMMC and boot normally.\\