Reply To: Portable Data storage memory cards

[deleted]

Does your SSD really need 12V ?
-Remember that the “12V” you supply to the board will go directly into the LP4 connector, so make sure it doesn’t exceed 12V (some harddisks tend to break at only 5% overvoltage – see the specifications for the particular device).

-If your SSD only needs 5V, you can run the EspressoBIN on 5.2V (I use a 5.9V / 3.8A supply).
This also reduces the heat coming from the board.

I assume you’ve already downloaded the EspressoBIN schematics. 😉
If you search for “12V” in that PDF, then you’ll quickly find everything that’s connected to the barrel DC-input jack, including the over-voltage protection Zeners.

To drive the EspressoBIN, the DC-input is fed into the RT6220. The datasheet for RT6220 is easily found on the net.
Looking at the minimum and maximum voltage for the input voltage, it states that it must be between 5.2V and 23V (see the application circuit similar to the circuit used on the EspressoBIN; that would be the top circuit delivering 5V).

Now, since the only other device using the DC-input is the harddisk via Molex, then if you’re using a non-12V drive, you do not need that high a voltage. 😉

… Shipping – yes, that’s usually expensive.
I tried looking at Kenable.co.uk; I usually purchase my Cat6a and USB cables from them, since they’re high quality (pure copper, very low resistance). I found one USB3.0 card reader.
Their shipping price is usually very low for small packages: £2.99, so a total value would be £15.
(Do yourself a favour if you’re purchasing the card-reader from them; throw in a few USB cables that Kenable makes themselves, then you won’t have to worry about poor cables. Those USB-A to Micro-USB cables that come with the EspressoBIN are not of a good quality).

… I understand that you’re going to use a SSD drive. I do not know if it’s wise to use a journaling file system on SSD; this likely depends on the SSD itself, but I believe newer SSD drives are more reliable than older ones.
If you change your mind to use a 2.5″ harddisk, then I’d recommend using the journaling file system (eg. ext4 with journaling enabled), so that in the event of a power failure, your data won’t be easily corrupted.

You may wish to …
1: Install your Linux on the SSD itself (or even better: eMMC if you get an EspressoBIN with eMMC), so it boots from the SSD or eMMC. This will free up the micro-SD slot. As a bonus, this makes your box much more stable.
2: Use the MicroSD card slot whenever you want to backup a microSD card, because this will likely be faster than the one on the USB3 card reader (the CPU has a built-in high-speed hardware SDIO interface).

(as for myself, I’m booting the “official” 4.4.52 ubuntu from SATA and have no micro-SD card inserted in the EspressoBIN, so I can say that this is ‘doable’ without too much effort).

I don’t know if I can provide you with much additional input – I hope that you can use at least one of the suggestions. 😉