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8 years, 6 months ago.
Where is pin declarations to associate SDFileSystem library to SDCard interface present on F746NG?
Where is pin declarations to associate SDFileSystem library to SDCard interface present on DISCO-F746NG?
Any example?
Question relating to:
![](/media/cache/platforms/DISCO_F746NG.jpg.50x50_q85.jpg)
4 Answers
8 years, 6 months ago.
https://developer.mbed.org/users/mimi3/code/SDFileSystem-neil/file/246743d68d90/main.cpp
SDFileSystem sd( MOSI, MISO, SCLK, CS, "sd",NC,CD_TYPE,12*1000000); //SDFileSystem sd(p5, p6, p7, p8, "sd"); // the pinout on the mbed Cool Components workshop board
The SDCARD interface is SPI so standard SPI definitions should apply: MOSI, MISO, SCLK, CS :
https://learn.adafruit.com/adafruit-micro-sd-breakout-board-card-tutorial
https://en.wikipedia.org/wiki/Serial_Peripheral_Interface_Bus
NSS = Negative (active low) slave select
Thanks for your answer Sanjiv ... but your response refer to use external SDCard adapter on arduino interface on card ...
To clarify my question, i am not able to access the internal SDCard interface present in the board and has no easily documentation on this topic.
I am triyng to use maping present on ST documentation ... described bellow:
// From Example ... // SDFileSystem sd(p5, p6, p7, p12, "sd"); // MOSI, MISO, SCLK, SSEL // // From STM32F746NG DISCO Board (look at http://www.st.com/st-web-ui/static/active/en/resource/technical/document/user_manual/DM00190424.pdf page 24) // DI = MOSI = PD_2 // DO = MISO = PC_8 // SCLK = CLK = PC_12 // D3 = CS = PC_11 SDFileSystem sd( PD_2, PC_8, PC_12 ,PC_11 , "sd");
But the simple execution of this constructor freeze the board and turn of the screen ...
The problem persists ... :-(
posted by 20 Jan 20168 years, 6 months ago.
Maybe, Disco-F746NG does not have a SDIO and its SPI mode, but there is a SD/MMC interface. So , It needs to implement a bridge interface of SD/MMC driver in the SDFileSystem class if you want to use it.
8 years, 6 months ago.
I agree with takuya m, it appears that the on-board SD card interface only is wired through the SD/MMC interface. You can see that from the schematics link here: http://www.st.com/web/catalog/tools/FM116/SC959/SS1532/LN1848/PF261641?s_searchtype=partnumber
From the datasheet for the part here: http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/DM00166116.pdf
The pins used do not have a SPI alternate function. The basic operation is similar for SPI vs SD but you need to set up the registers for SD/MMC. There might be some example code out there for this... take a look at some other vendors who have implemented this function on their boards (hint: Embedded Artists for LPC4088).