Suggestions on MicroSD Breakout Boards

varnon

Hi guys, I'm shopping for some micro SD breakout boards. I'm really looking to make some suggestions for some colleagues.


I developed a library of code for common functions that my colleagues and I all need (I'll post it when it is well tested), and now I am looking to suggest some hardware. I think I will likely continue to use the gadget gangster USB/Martin Hodge's DNA platform. http://mghdesigns.com/propeller/mgh-designs.html However, for my colleagues that are not as experience with these things, I think the quickstart might actually be better. Part of me kind of hates the quickstart for things like not having a barrel jack and not having real buttons, but it really is useful as an intro to programming with the propeller. The touch pads and the LEDs are really good for learning demonstrations and for debugging code. However, it lacks one thing I need, an SD card slot.


I have seen quite a few SD card breakout boards. The one I really liked was the gadget gangster board. http://gadgetgangster.com/find-a-project/56?projectnum=230 I liked it primarily because it included the pull-up resistors. I actually don't completely understand what the resistors are for, and I've never used an SD card without them. But I do really appreciate that the inclusion of the resistors on the board means less components to attach to the propeller. Of course I'm not afraid of a few resistors, but I would really prefer to suggest something for my colleagues that will require as little effort as possible. My colleagues are not programmers or electrical engineers, I want to make it as simple as possible. The gadget gangster module has been in and out of stock frequently, and now just seems to be out of stock. I have also seen one of the recent gadget gangster protoboards that has a slot to solder on an SD card slot. It looks really great, but it has been in and out of stock as well. I love the gadget gangster stuff for myself, but honestly I want to be able to recommend something that is more consistently available for my colleagues, or at least recommend several options.


Has anyone seen something similar to the gadget gangster SD card board that includes the pull-ups? Are there any break out boards that I should avoid? Do the pull-ups really matter? Parallax's data sheet for their breakout board http://www.parallax.com/tabid/768/ProductID/597/Default.aspx just shows a direct connection to the pins, and doesn't seem to include any pull-ups on the board. Any other thoughts?


As always, any thoughts are greatly appreciated.

cavelamb

http://www.ladyada.net/products/microsd/
https://www.sparkfun.com/products/204
https://www.sparkfun.com/products/544

n_ermosh

Parallax's SD adapters work perfectly with direct connections to pins (I wonder why :P). I have used it and if you look at the last page of the documentation, there is a schematic of the board, where you can see the pins all pulled up. It looks to be exactly what you are looking for. The standard SD adapter comes as a board and parts that require it to be soldered and assembled (not a good choice if you aren't good at SMT soldering). The microSD adapter comes preassembled and ready to use.

WBA Consulting

I don't make them to sell, but have a few boards to make my version of a "Micro-Micro SD adapter"

http://forums.parallax.com/entry.php?239-Now-that-s-a-Micro-Micro-SD-card-adapter!!!

MacTuxLin

Same here, I have made one that's meant for my robotic controller ...

varnon

I appreciate the suggestions.


I saw the adafruit board before. I understand the purpose of the level shifters if you were using an Arduino, (and I got that the level shifters while useless for the propeller wouldn't interfere with anything) but it still wasn't really clear to me if it had the necessary pull up resistors.
Unless I am mistaken, the sparkfun boards do not have the pull ups. From what I understand, the pull ups aren't needed 99% of the time, but I would just rather have them anyway. (And I'd rather have them built in.)


Of course I completely ignored the schematic on the parallax board. Oops! That one seems to be a good fit for me. It is a little bit more expensive than the sparkfun board, but it balances out in shipping if I am ordering other stuff from parallax.


I love the custom boards. I can't believe how tiny that one is. My eyes and hands just aren't good enough to put something together like that, but it sure is cool.


Anyway, thanks for the suggestions.

Leon

I made my own PCB for a MicroSD in a MiniSD adapter:

http://www.leonheller.com/Propeller/miniSD%20BO/miniSD.jpg

I only used one resistor, a pull-up on nCS. It plugs into a socket on my Proto board.

PiXEL8

To save time and money I usually solder directly onto a microsd to standardsd adapter. This is what I did for the DC20 badge.

-PiXEL8

max72

Check also the pictures here..
You have plenty of options :-)
Massimo

http://forums.parallax.com/showthread.php?141959-sd-card-and-quickstart-board

Dave Hein

PiXEL8 wrote: »

To save time and money I usually solder directly onto a microsd to standardsd adapter. This is what I did for the DC20 badge.

I have done that as well, except that I only use 7 pins instead of 8. Also, there is a small amount of raised plastic at the end of the connector that I file down so the pins lay flat on the connector.

PiXEL8

Dave Hein wrote: »

I have done that as well, except that I only use 7 pins instead of 8. Also, there is a small amount of raised plastic at the end of the connector that I file down so the pins lay flat on the connector.

I used 8 pins for extra support and it does lay flat on a pcb. I'm waiting on a perf board and few other items to complete my badge upgrade. Once it's done I'll post some pics in the project section or on the DC20 badge thread.


-PiXEL8