Forums Microcontroller Boards ARM ARM7 with SD card

ARM7 with SD card

Link to this post 01 Dec 14

I am working on interfacing SD card with ARM7 (LPC2148) via SPI port.<= 2GB cards are detected, but not >= 4GB.
Any idea?
Any suggestions?

Link to this post 03 Dec 14

Dear Natarajan,

Could you tell me the File system used ie the fat16, fat32 and the library that you are following (the firmware).

The block size may vary depends on the capacity.

A small hint is mentioned in he following link,

Link to this post 04 Dec 14

I am not speaking about file system. It is regarding basic initialization of SD/MMC card. CMD0, CMD8, ACMD41, CMD58 (OCR), etc. The routines work for <= 2GB cards and not beyond that.

Link to this post 04 Dec 14

Dear Natarajan,

Can you tell me the hardware and firmware details, ie the processor, the board name etc.
And are you sure the hardware and firmware supports greater than 2gb?

Whats your application, simple read write or copying large files?
Everything matters, so put some additional details...

What type of card inserted SD card or SDHC card. If card is SD card then tell me it is version1 or 2.
There are many classes in SD card Class4, Class6, class10. Some cards wont support spi mode.
Is the new card formatted to your file system?

Link to this post 11 Dec 14

LPC2148, boot loader V.2.1 (taken from
The firmware consists of initialize SPI, CMD0, CMD8, CMD58, ACMD41 etc.
All cards I tested formatted as FAT32.
Tested on 512 MB, 1 GB, 2 GB, 4 GB, 16 GB cards.
Whether it is simple read or write or file handling, the card has o be INITIALIZED. But > 2 GB card is not getting initialised.

Link to this post 12 Dec 14

Hello sir,
i'm using lpc2148 arm7.
i also want to do some task like knowing/ reading card size or vendor name from SD card or reading or writing some files from SD card and display on uart.
i have one code that simply for detection of card that tells on uart card fail or card pass.
i have attached one code please find and tell me something so that i can do thing other than simply card detection.
UART0 is used.
help me if any one can do..

Link to this post 15 Dec 14

I went thru ur code. What exactly is ur query?

Link to this post 19 Dec 14

Sir,i want to know the card size and vendor name or id.
if possible i want to write and read the one single text file and want to send that data on serial.
please help me how to modify above attached code to know this.

Link to this post 19 Dec 14

Hello Natrajan sir,if you have any other code which will help me for this tell me..

Link to this post 02 Jan 15

Hi Embedded Developer,
Sorry for late reply.What exactly is your requirement?