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Altera_Forum
Honored Contributor
Honored ContributoruClinux MMC SPI Driver
Just to let everyone know, an MMC SPI Driver for Alteras SPI Core (modified) is in the works.. currently, cards can be recognized, read/write, and even partitioned.. but some bugs are being worked ou...
Altera_ForumHonored Contributor
Honored ContributorThanks hippo,
I forgot to add this; there is support for a status LED, configured via make menuconfig. I STRONGLY suggest those who want to use the driver to enable this feature. The reason why is currently, there is no DMAing of data. So if you are transferring any files that are reasonably large (>1 MB), your uClinux system will lock up whenever the IO Scheduler kicks in to actually do the transfer. With the LED enabled, you can see when the MMC Card is being accessed, so you know why it locks up periodically. Also, card insertion/removal is fine if it's not done in the middle of a transfer. Make sure you mount/unmount al filesystems properly before removing a card, or it will crash the kernel. Im' not sure if this is a uClinux bug or a bug in the driver. If you want to see what I mean, create/mount a filesystem on the MMC card, mount it and write a couple of files to it. Wait until it's done, and then eject the card. If you try and do an 'ls' while you are inside the filesystem, it will hang because the dev. node is no longer active. This is a relatively minor bug though. The overall speed is more of an issue if anything. Suggestions are welcomed.
