Ideas for a next usb3.1 emmc reader update

I have been using the new 3.1 reader and it’s working fine as it should, however I kinda miss two things which I think are necessary, maybe some people will also find it handy.

1 - Status LED - so you can see when the pc is completely done with reading or writing
2 - EMMC position instruction - the board does not have a print indicating which is the right position of the EMMC memory. It could be done something similar to the emmc to sdcard reader.


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For (1): I’d suggest that you should NOT rely on LED’s to judge whether it is “finished”. An LED can stop blinking while a data transfer is incomplete, because the CPU is busy doing something else. The only safe way to determine if a device is safe to disconnect, is to ask the thing that is doing the writing.

When you use the “dd” command, it will not return until the write is completely synchronized;

# dd if=gpt.img of=/dev/mmcblk0 bs=1M
<output of dd command... blah blah blah>
# <-- when you see that, it is synchronized and safe to remove

Similarly, when you unmount partitions, the umount command will not return until the filesystem is synchronized;

# umount /dev/mmcblk0p20
<pauses for as long as it takes to sync the FS>
# <-- it is now synchronized and safe to remove, PROVIDING that ALL filesystems are unmounted.

For (2), I don’t know if you realize this, but the connectors on either end of the eMMC module and adapter board are actually different sized. You CAN’T plug it in backwards.

We obviously don’t have to rely only on the led status when is writing, but at least with an LED I can know if my emmc memory is damaged or if the reader is damaged in case it does not show anything in my PC.

And it’s quite obvious that there is a difference in the size of the connectors of the emmc, however if there are people that are starting right now, and learning how to use these things they might not realize it. Or even us during the rush times.

Those are pretty simple things, that we see in other adapters and external cases. And also can be very hand for some people.

The current usb3 emmc reader is full of components, i am not sure if it’s possible to add led. The indicating label is good, something we forgot to add.