copy machine (SD to SSD hard disk)

bastler59

Member
Hi,

during holidays I'm taking a lot of photos. Before corona I used a notebook with card reader and connected my SSD via USB. In the evening I made copy action in hotel room. But I want to take less equipment with me.

A smartphone (Android) with TotalCommander and an USB hub with additonal power input is possible. Sometimes I have to remove card reader or SSD from USB host and attach again, because smartphone doesn't recognize them at once.

So my idea: take a microcontroller for that.
I see there is USBHost_t36 library for mass storage and a Teensy 4.1 has card reader.

A few pictures are on microSD, most are on normal SD cards. So I need card slots for both sizes.
On Teensy 4.1 board the 8 connectors from card slot are going directly to processor? No pins at the edge of the board?
Can you please tell me manufactor and type of card slot you use?
So easiest way is to use/make a "microSD Sniffer"? PCB should have same thickness like a microSD 0.7± 0.1 mm?

Bye
Jürgen
 
Thanks.
Never seen such an adapter before.
Not sure, if it is a good idea to stick in and pull out such an adapter several times. A pcb material of 1.5mm and 35µm cooper is much thicker than a microSD.

My suggestion for a next version: "half pins" at the right side of the teensy boards (don't know the exactly term ... such pins the ESP32 modules have). So with a short pin header it would be possible to make connection without blocking the microSD slot.

Bye
Jürgen
 
Perhaps 'castellated' is the term for the half holes?

Giving a look at the T_4.1 PCB top and bottom the PCB would have to grow from the 2.4"/24 pin length adopted since T_3.5/3.6 to expose the SD cards SDIO pins any better.

Not sure about the thickness of that adapter board - but indeed the PCB material selected is usually thinner to match the expected size of the SD card socket so it shouldn't stress it.
 
Perhaps 'castellated' is the term for the half holes?
That's the term, thanks.

At the manufactor, where I order prototypes from time to time, castellated holes are extremly expensive. Even for 1000er batch it doubles the price. And yes, they would make board larger.


microSD Sniffer: I looked at several products, none of them has information about pcb thickness.
I can order boards with 0.6, 0.8, 1.0, 1.2 and 1.6 mm for the same price. So it should be no problem. But it is not my favourite.

Bye
Jürgen
 
For what it is worth, when I was playing with my own, I believe my last order OSHPARK was:
Screenshot.png

I believe this was used mostly on T3.5/6, I know I played with them on T4.1 as well. Don't remember how well they worked.
If they felt a little too thick I would simply sand the one side of it that had no traces... Only the part that inserted into the slot.

If their etch wore out, would simply use a new one.

I went with the .8 version as it appears to be very close to the thickness I measured of a couple of MicroSD cards.
 
Sparkfun sells this board. The design is open source, and the Eagle files are available, so you should be able to get your own version made:

Before the Teensy 4.1 came out, there was a lot of interest in adapting the Teensy 4.0 solder pads for bringing out the micro SD card. Since the 4.1 came out, my personal interest in doing that any more has dropped down to nil (but I still have a few Teensy 4.0s soldered up from those days, and I have a bunch of PCBs I had made, that I can send out if desired, but I'm not sure if I have ones with USB host coming out):

Of course, unless you have a stock of Teensy 4.0's, it probably isn't useful to do those boards.

However, it occurs to me, that the simplest approach is to just get a USB hub with at least USB A output ports and a USB card reader. I would suggest getting a USB hub with a separate A/C plug just in case the SSD needs more power than the Teensy can provide. And several of the USB hubs meant for travel already have card readers built-in.
 
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Sorry, I missed notifications about new answers.
Thanks to @KurtE and @MichaelMeissner for your suggestions.

I'm living in Germany. So it is useless to order something from a dealer in USA. A small parcel cost between 15 and 20 €, for the sum I have to pay 19% VAT and UPS charge a minimum of 15 € handling fee too. One exception is Digikey, where I can pay in Euro and they will add VAT, so an order above 50 € will be free from additional charges.

At the moment I have to get familiar with my Teensy 4.1 boards.
 
I'm living in Germany. So it is useless to order something from a dealer in USA. A small parcel cost between 15 and 20 €, for the sum I have to pay 19% VAT and UPS charge a minimum of 15 € handling fee too. One exception is Digikey, where I can pay in Euro and they will add VAT, so an order above 50 € will be free from additional charges.
If you are buying from oshpark, they just put the item into an envelope and charge something like $1 postage/carriage. Usually doesn't get picked up for VAT or Customs duties (at least in the UK).
 
An order takes 2-3 weeks from OSH Park to Germany. Don't be too shocked at the outrageous price for PCBs that don't even have acceptable milling outside and take >1 week to get produced. Was Platinen angeht, ist OSH zumindest für europäische Kunden keine akzeptable Lösung. Es ist halt amerikanische nicht-qualität zum frech überhöhten Preis. Aber es gibt günstige Teensys dort!
 
An order takes 2-3 weeks from OSH Park to Germany. Don't be too shocked at the outrageous price for PCBs that don't even have acceptable milling outside and take >1 week to get produced. Was Platinen angeht, ist OSH zumindest für europäische Kunden keine akzeptable Lösung. Es ist halt amerikanische nicht-qualität zum frech überhöhten Preis. Aber es gibt günstige Teensys dort!

As far as boards are concerned, OSH is not an acceptable solution, at least for European customers. It's just American non-quality at a cheekily inflated price. But there are cheap teens there!

Note: I have not had any major problems with OSHPark, but I mainly now only use them for small boards. The adapters I showed earlier in this thread cost < $2.00 for 3 of them with free shipping (in USA)

For larger boards I have used a few different places. The most recent PCBWay (https://www.pcbway.com/)
For most smaller boards it costs something like $5 for 10 boards plus shipping. I typically have used DHL with them (again USA) and I believe again for smaller boards shipping is about $15

Not sure about their shipping options to Germany, but that might be an option.
 
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The last boards I ordered @OSH had "mousebites". Each. They were obviously broken out of a larger circuit board by hand.
What is the price for a 100mm x 100mm board? ;-)
 
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Like KurtE and others, I have used OSH Park for a variety of PC boards (both for work and for my hobby projects), the smallest at 25mm x 25mm, & the largest at 250mm x 120mm. In my experience, OSH Park's PCB quality has been consistently high, & I just spin up my wife's Dremel tool to quickly smooth out the minimal break-apart spots around the outside edges. I have been very pleased with the quality of their products & the speed of their production/delivery (to the USA). For me personally, I am willing to pay the very slight premium price (vs. that available from non-US vendors) for the assurance that I am not getting potentially poisonous PCBs laced with toxic heavy metals, etc.

Mark J Culross
KD5RXT
 
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