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AM335x 8-bit Data Bus eMMC Communications Problems

I have been trying to get the drivers from the Industrial SDK to work with a custom piece of hardware that has an MTFC4GLDEA-0M_WT eMMC chip attached to the MMC0 bus of the AM335x part.  It is set up to run on an 8-bit data bus, which is not directly supported by the MMCSD driver that comes with the SDK...and so I modified the code a bit to, what I thought, would make it work with an 8-bit data bus.  I have done about 16 solid hours worth of low level troubleshooting and think I narrowed it down to card detect (CD) being the problem.  According to the technical reference manual, SPRUH73K, the Bus power (SDBP of the SD_HCTL register) needs to properly detect a card...well...I can't 'properly detect' a card on the current hardware.  For one, the eMMC IC provides no CD line, and two I cannot just tie one of the two possible selections for CD pins high/low as both are being used for other circuits.  I tried forcing CD to true by means of setting the CDSS and CDTL bits in the SD_HCTL register, but the Bus power bit just won't set.  Also, when I try sending a command over the CMD/CLK lines, there is no activity (the first command is the INIT command prompted by setting the INIT bit of the SD_CON register).

Have have tested the hardware through the use of the SD_SYSTEST register and so I know that the connections between the AM335x part and the eMMC IC are good.  So it is strictly a driver configuration issue.  Also...I know that the registers can be set up properly because the bootstrap loader in AM335x boot ROM is playing with the CLK and CMD lines at sys boot (I threw an O-Scope on those two lines).

I am by no means an MMC expert, and so I expect the answer to this issue may be very simple...but I just do not know.  Any help is greatly appreciated!

Cheers!

- Trevor