QSPI communication with MMC : some problems.

Hi all,

I have problem reading an MMC card.

I have the MISO signal  coming from the MMC as follows.

http://www.geocities.com/qspimmc/miso_signal.jpg


Here are my questions:


1)
I am using QSPI ( SPI) and Im not sure how to interpret this signal
which is above. Is the MISO signal defective on the MPC555 side?

Im running the CLK at 143khz , Im using a level translator MAx3002E to
match different voltages of the MMC and my host controller 

The mmc is at 3.3 V  and my micrcontroller is at 5 V.

THe interface is achieved with the level translator.

Can anyone tell me if there is anything wrong in the MISO signal?

2)
I want to disable the queue and intialize the MMC . I read the QSMCM
manual but there is no explicit way of having only one instruction in
the Recieve ram or the transmit ram which can be used for SPI
communication.

Is it necessary that we have to intialize the queue, the transmit and
Recieve Ram to start using the QSPI module ? Can we use the queue
pointers to use limit the   number of entries in the Transmit buffer
which can be transmitted?

For example , we have 32 entries for Command ram , 64 each for
Transmit and recieve ram

I want to create functions which can send "one" byte over the SPI channel 

but with the queue, it seems necessary that I have to intialize all
entries before I start the QSPI . Is there any way of doing it without
intializing the queue  with a set of values , rather than  adding
entries to the QUEUE one at a time when we want to send/ receive
information?


3)
Is it possible that we can write entries in the Transmit RAM and
recieve bytes in the Recieve Ram at Runtime ? i.e when the QSPI is
running ( assuming WRAP around mode is used).



4) IS it necessary that we have to use pull up resistors on the MISO
and MOSI signals on the MMC side of the elctrical interface ? If so,
what are the ideal values of the pull up resistors?


Thanks in advance.







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