SD Card breakout board

[juliuscaesar]

Posted on May 21, 2017 at 22:05

hey guys,

i'm interested in a SD breakout board for my STM32F427 disco board.

I'd like to use the MCUs SDIO Pins for the communication with the SD breakout board.

Of course when you search for 'sd breakoutboard' there are millions of different boards, however i was hoping if someone could recommend my a specific sd breakout board

I have read the manual how to access an SD card using FatFS. If i got the manual correct, there are 2 ways of accessing an SD card, first way is to use SPI, the second is to use SDIO Pins. If have decided to use the SDIO.

http://entesla.com/micro-sd-breakout-board

 

The typical SD breakout boards have typical SPI pins (CS, MOSI,MISO,CLK). Since I'd like to access the SD Card not via SPI but via SDIO i was wondering if i could use these boards anyway?

For my (1 wire) SDIO solution i need 1 data in/out pin,  1 clk pin and 1 cmd pin.

Thx for your support

[Tesla DeLorean]

Posted on May 22, 2017 at 14:14

F427??

The board you've shown is not suitable. You don't need a regulator and level translation. The SDIO data pins need to be bidirectional.

Get a simple socket-to-pins adapter, add pull up resistors.  Run from 3V 

[Tesla DeLorean]

Posted on May 22, 2017 at 17:04

http://www.ebay.com/itm/1pcs-NEW-Micro-SD-Card-Module-Slot-Socket-Reader-/282123611334

 

http://www.ebay.com/itm/Micro-SD-Card-Breakout-Transfer-Board-Converter-For-TF-Card-Memory-Module-2mm-/381920586431

 

[juliuscaesar]

Posted on May 22, 2017 at 19:20

sorry my fault: little typo :o

I'm using the STM32F429I-DISC1 board.

In my current configuration i can only use 1 Datapin (the other possible SDIO data pins are used by the touch controller

:(

)

So you are recommending to get a pullup resitor for the 1 data pin. What about the Clk and CMD pin, should i get a pull up resistor for those 2 as well?

Thx for your help so far

[Tesla DeLorean]

Posted on May 22, 2017 at 19:55

The F429I-DISCO has a clash with LCD R2 as I recall.

Haven't tried 1-bit SDIO on it. Even if you don't connect them to the STM32 I'd recommend pull-ups at the card end for Dx and CMD pins

Consider the F469-DISCO?

[juliuscaesar]

Posted on May 23, 2017 at 18:54

'The F429I-DISCO has a clash with LCD R2 as I recall. Consider the F469-DISCO?'

I already got the F429I Disco Board However i bought revision 1 aka 'F429I-DISC1' maybe that issue is fixed there. The display i working fine at the moment, however i'm not using the HAL LTDC routine for the display. I'm contacting the Display via SPI. Seems to work fine

Back to topic though. I bought an SD card expansion without level shifter. I will use 5    47kOhm Pullups resisitors then´, and hope that this works out for me

Thx for your help so far!

[juliuscaesar]

Posted on September 27, 2017 at 22:41

Hey

i finnaly got my sd breakout board.

I connected as shown in your picture, however it does not work somehow

:(

I'm using 1bit bus width, therefore i'm only using D0, D1-D3 are not connected to the MCU but they are connected to 47k pull up resistors.

I generated a sample project with cube MX. I did not make any adjustments to the generated code yet.

At startup BSP_SD_Init() is getting called, and within that SD_PowerON().

As far as i can tell SD_PowerON() sends serveral cmds to the sd card.

1st: CMD0 go to idle

SDMMC_CmdGoIdleState() =>OK

2nd CMD8 SEND_IF_COND

SDMMC_CmdOperCond() =>Returns with SDMMC_ERROR_CMD_RSP_TIMEOUT

Do you guys have any ideas? Connection seams to be working if SDMMC_CmdGoIdleState() returns with OK right?

[Marco1]

Posted on October 19, 2017 at 11:32

Have you solved ? I have same problem !!

[LMI2]

Posted on October 19, 2017 at 19:19

I have a SDIO adapter or breakout board what ever you call them from Waveshare. I have not used it because I needed only the STM32f407 from the package. But it probably works because there is demo code for it from Waveshare.

So in case of big problems that is an option.

[juliuscaesar]

Posted on October 19, 2017 at 22:20

hey

nope no luck yet. The problem still exists.

I'll have a look at the waveshare code. Looks like they are using regular SPI instead of SDIO. Maybe that works better