Hello, I am a software engineer at Rockwell Collins. I am currently trying to debug an interface between the OMAP-L138 Arm9 Core and a Micron eMMC on-board device. I am running into some problems getting the Micron eMMC to respond to the OMAP MMC Controller.
The eMMC is a Micron MTFC16GBJDEC-4M IT. I have been following the instructions in the JEDEC Standards and the OMAP-L138 spruh77a Reference Manual.
For the initialization and card identification process I have the MMC clock selected for 300 KHz. With the Command Line in open-drain mode, the software issues the CMD0, GO_IDLE_STATE, command with Argument 0x00000000. Next the software issues the CMD1, SEND_OP_COND, command with Argument 0x00000000. We get back from the eMMC the following response: bits 47-40 = 0x3F (should be 0x01?), bits 39-24 = 0x00FF (device not ready), bits 23-8 = 0x8080, and bits 7-0 = 0x00.
After waiting for the Response Ready bit to be asserted in MMCSTAT0, the software issues CMD2, ALL_SEND_CID. Unfortunately, the eMMC does not respond to this command. There is only a single eMMC device on the board. We have connected an o'scope to the Command Line and it and the command signals look good.
What should I look at next?
Thanks.
Rick Demers
Rockwell Collins
Melbourne, FL