microSD on EMX

Hi,

I’m a bit unsure about how to connect a microSD to an EMX module.
I have read several related questions on the forum, but did not find an answer to mine.

The connector I want to use (Multicomp 460DE08C3) has the following pin layout:

1 DAT2
2 CD/DAT3
3 CMD
4 VDD
5 CLK
6 VSS
7 DAT0
8 DAT1

So, is this the correct way to connect it to EMX?

1 > IO40/SD_DAT2
2 > IO39/SD_DAT3
3 > IO44/SD_CMD
4 > SD_POWER
5 > IO42/SD_CLK
6 > GND
7 > IO43/SD_DAT0
8 > IO41/SD_DAT1

I’m a bit worried about pin2, which has to do with the CD part of that pin. Should there not be a seperate CD pin on the connector?

I’m a bit confused because the pins are diffrent compared to “standard” SD card, like beeing used on FEZ cobra for example.

Anybody who could help me understand?

Thanks!

DAT3 can optionally be used for detect but we do not support that. If you need detect, then you need a card with detect pin.

Wow, your fast!

Oh I see. No, I do not need card detect, because the card will always be in the holder. I will use it as storage for application settings and html files for the embedded webserver.

So this pin layout is correct then?

1 > IO40/SD_DAT2
2 > IO39/SD_DAT3
3 > IO44/SD_CMD
4 > SD_POWER
5 > IO42/SD_CLK
6 > GND
7 > IO43/SD_DAT0
8 > IO41/SD_DAT1

No one able to confirm the pin layout?

I have to order the boards by the end of the week and it would be nice if I would know for sure…

They look correct but obviously we do not give you a wrong answer. Please double check with one of the numerous open designs we provide.

Gus,

Thanks for your answer. I will check your designs and see if I can find one with microSD on it.

@ NickS: maybe this information can help you out: http://elasticsheep.com/2010/01/reading-an-sd-card-with-an-atmega168/

Your pin layout looks fine. But I would search a microSD slot with mechanical card detect switch, so you can detect insert/removal of the card. F.e. the DM3D-SF http://www.hirose.co.jp/cataloge_hp/e60900232.pdf

Wouter,

Thanks a lot! The link you send me in your first reply is very helpfull. I was a bit confused because the pin layout is diffrent compared to a “regular” SD card.

I I do not actually need CD for this project, but it’s likely that my next project requires it. I might as well do it right the first time…

I get started on drawing the Hirose connector in Eagle.

Prettige avond!