Micro SD card insertion techniques

[emcniece]

That micro SD can be a bit of a pain to get in there with tight clearance from the header pins! Out of curiosity, do you guys have any special/hot moves for getting that sucker to bed?


http://www.youtube.com/watch?v=8JRUGL3j0dQ - I hold the board at a 45 degree angle (to the desk), ease the card in with my fat fingers, and if it lands in the right vicinity I just shake it once or twice to get it to sit. Apologies for the terrible video.


Is anyone else doing something different?

[digistump]

That's about what I do - a pair of needle nose pliers or tweezers works well if handy - with no shield on I usually put the card down to the side of the slot and then scoot it over with my finger. For removal - once it is out of the slot I use tweezers or shake it out.


To explain the choice of socket a bit:


Location: The only places it could go were all like that spot - otherwise we would have had to expand the board alot to put it outside the headers or put it on the back - the first we were set against, the later we couldn't afford.


Socket choice: So why not a hinged socket - to be blunt - they were all junk, because they are made for very low insertion count all the ones we tested were delicate, didn't hold a card well, or didn't work at all - if we had found a good affordable hinged socket we would have gone for it in a second.




Its not the perfect slot and if we do a second run I'll likely revise it - but it does keep the card well protected!

[emcniece]

Haha it definitely protects it well! No complaints here to be honest... it's a fun post for a Friday! 


I'm almost a little surprised that you guys didn't mount anything on the bottom of the board. Do you think the team could have done more in terms of hardware if the DigiX was a 4-layer board?

[digistump]

Running assembly on the backside would have added about 25% to the cost of production, 4 layer another 25% - so if we wanted to say make the smallest DigiX possible and break arduino layout compatibility we probably could have made it half the size (or perhaps a third more stuff) - but while I think the DigiX is a really good deal for what you get, it still is more than I think a development board should ideally cost (blame it on the Digispark). So making a board that was say $99 (production) and $200 (beta) wasn't really something I was interested in.


The other motivator is I like to keep things easy enough to copy/remix/make for everyday makers - double layer boards with single sided assembly goes with that nicely.


An interesting fact on the DigiX - I spent well over a week trying to get it routed (at all, not just well) on double layer layout (Arduino uses a 4 layer for the due with less on it) - it made me finally try topographical routing (no corners, all flowing lines) and that is the only way I was able to route it, it took several months to clean up the routing (with a few prototypes in there) to get it where it is. That is why if you look at the traces they look crazy and unlike almost any other board.



I'm working on a 4 layer project but it is more in the multiple Ghz range of power.


I think it would be fun, for the sake of fun, to do a double sided assembly Digispark on four layer with a micro usb connector and edge connections for the outputs - I bet I could get it under 1/2" square with the same features - but I haven't had time for projects like that in awhile (baby+day job+business) which is a good thing (success!) but I still hope to retire some day and pursue the fine art of building the small simple USB boards and the like.