eMMC5.0 connection to iMX6's SD4 port

[kircpat]

Hello,

We are connecting eMMC 5.0 memory (64GB from Sandisk) to iMX6's SD4 port. The Sandisk part has RCLK (STROBE) output pin. I've couple of questions:

1. Can I configure/force the Sandisk part to run at eMMC4.41/SDR/HS200 speed? From another post someone confirmed that you can't run eMMC5.0 HS400 mode with iMX6

2. Seems like the STROBE output from eMMC5.0 memory is only used in HS400 mode. Can i make STROBE output as No Connect (ie float this pin on the Sandisk memory)

We've no intention to use all the bells and features of this eMMC 5.0 part. We just want it to work as a standard eMMC part in 8-bit mode

I've attached the eMMC5.0 datasheet from Sandisk

Thanks for your help in advance!

Chirag Patel

[igorpadykov · Accepted solution]

Hi Chirag

you are right, HS200/400 mode is not supported on i.MX6Q,

supported modes are described in sect.4.11.4 Ultra High Speed SD/SDIO/MMC

Host Interface (uSDHC) AC Timing i.MX6DQ Datasheet

http://cache.freescale.com/files/32bit/doc/data_sheet/IMX6DQCEC.pdf

eMMC 5.0 parts are backward compatible with older specs,

seems STROBE output can be left unconnected.

Best regards
igor
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[kircpat]

Hi Igor,

For clarification purpose, does SD4 port on iMX6 Quad also support emmc 4.41? The reference manual indicates only SD3 port supports 4.41 (see attached snapshot from ref manual).

What's mode does SD4 support? DDR, SDR?

Thanks
Chirag

[kircpat]

Igor, thanks for your prompt response!