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Platform forum

tanbakoo , 12-21-2016, 12:04 PM

Hi,
I see in openrex it doesn’t have emmc on board and only have a micro SD card slot.
1-Is it reliable to boot OS from a micro SD card? Is there any risk during the time of device lifetime with micro SD instead of emmc?
2-In many device need an internal memory and a removable memory, so why you use only one micro SD slot? also in expansion connector you didn’t insert any micro SD pin (IMX6 have 4 micro SD interface) Do you have any solution for me?
Best Regards

robertferanec , 12-21-2016, 04:31 PM

1) For sensitive application I would recommend to use SATA. SD cards are not long-term reliable, but it may depend on how you use them (e.g. if you only read the SD card, they should be just fine). We didn't use eMMC, because it would increase price of the board.

2) If you need additional memory, you can use USB memory stick (USB is on the expansion connector) or SATA hardrive (SATA could be brought down to an addon board if needed).

I preferably use small SATA SSD drives - they are very quick, reliable and need only 5V for power.

tanbakoo , 12-27-2016, 12:02 AM

Hi Robert,
I want to use Tiny Rex with my own base board to have a emmc memory to have maximum speed of these type memories. Can you help me? each of 4 usdhc of IMX can work with emmc? Linux Driver of this board support each 4 usdhc interface? and also support emmc? what is the configuration of boot setting? what is the efuse setting?
Best Regards

robertferanec , 12-27-2016, 08:17 AM

@tanbakoo, you would need to test it.

- We have not done any eMMC testings (we do not have eMMC in our boards)
- We have not tested ALL uSHDC interfaces AT ONCE (we do not have any board with all the uSDHC connected)
- We have not done any special speed or performance tweaking, we use the standard settings delivered with the Freescale/NXP/Qulacolm Linux Kernel

We have done SD card stress testing (the interfaces which are connected on the Rex boards), these connections / interfaces pass all the tests.