Sd memory interface in assembly language

[jawaidarshad]

HI ALL EDA ENGINEERS,

i use 8052 based microcontrollers in my projects and use assembly language with m-ide studio
i need some sample code that write or read data from a sd memory card in assembly language
or if any one knows any site where i find sd card interface stuff ...

thanks

 

[doraemon]

Hello!

Is there any reason to do it in assembly language?
You can find a lot of code in C. on the net.

Dora.

 

[jawaidarshad]

Hello!

Is there any reason to do it in assembly language?
You can find a lot of code in C. on the net.

Dora.

Yes My Dear Friend,
Actually I start programming in assembly, and it is very easy for me,
and for C i don't know that at all.
i need some basics of how to communicate with sd memory

 

[jayanth.devarayanadurga]

You have to use SPI communication. You also need FAT16/32 routines for SD/MMC card.

 

[doraemon]

Hello!

You have to use SPI communication. You also need FAT16/32 routines for SD/MMC card.

As far as SD memory interface is concerned, you don't need a file system.
The subject line says "sd memory interface" not "write a file on SD".
Now if you want to write data readable by anybody, yes, you need a file system.

Actually I start programming in assembly, and it is very easy for me,
and for C i don't know that at all.

Well, I don't know if "I start programming in assembly" means that you are a beginner
or that you have started the current project in assembly, but anyway you should also
consider learning C. Of course, knowing basics in assembler doesn't hurt.
But you can use C with any processor. If you have written C code for PIC, then you
can use most of the same code in on AVR or any other processor.
And you can probably find code that mostly fits the processor you are using now.

Dora.

 

[jawaidarshad]

Dear jayanth,
Yes i am looking for some fat16/32 routines of how to read and write files from a sd memory.


Dear Dora,
I like to work in assembly, and i did many projects in assembly.
I feel very comfortable with it. and this is the main reason why i am looking in assembly.

OK if you think it is better to learn C then please tell me some beginner book for C language but it will take some time,
or if you provide me some example .hex file and i make an .asm of it.
so i understand the process.

 

[designer_003]

i wished to help you, but i dont have an experience in 8052 ... but it is very easy to interface sd card using PIC microcontroller using SPI protocol , however i think it is better to use mikroc compiler if you want to learn C for microcontroller or Flowcode if you are not interested in programming language ...

 

[jayanth.devarayanadurga]

Hi! jawaidarshad

For learning C good books are "Teach yourself C Programming in 24 Hours" and "C How to Program"
It is better if you learn C Programming. If you use mikroC Compiler there are libraries for SD/MMC Card and FAT16/32. You can easily write the code in C. I don't know much about PIC assembly language so I can't help you in assembly coding.

 

[jawaidarshad]

Dear designer_003,
MCU's i use in my projects is Winbond's W77E51640DL @ 40MHz, that is similar to ATMEL's AT89S52 but with a big code memory and i interface a Goldenpalm's 180X60 GLCD with it and i have designed a double sided board with some push button,s and memory slots and other stuff, fabricated in china, and that cost me big amount and time.
I have to redesign every thing if i change MCU or start C language, i have to make every thing for The LCD or all that will be wasted.......
AND i don't think it is important to learn C if you want to interface a memory card.

Dear jayanth,
i checked "C How to Program" that book contains more then 1000 pages and it will take long but i will give that a try
if you tell me the book or site that defines sd memory interface protocol i think i will find some thing.

 

[jayanth.devarayanadurga]

@jawaidarshad

Is your Winbond's W77E51640DL assembly language same as that of AT89S52? I haven't come across SD Card memory interface protocol. If I find one I will let you know.
https://www.edaboard.com/threads/24537/

 

[jawaidarshad]

Dear Jayanth,

Yes W77E516A40DL is same as AT89S52 with 64kb code memory, and some enhanced processes, speed, and things like that. It is 3 times faster MCU then AT89S52
well thanks for you help i will check above link hope i will find something usefull

 

[jayanth.devarayanadurga]

Check this link. It has a link for SD Card code in assembly

http://www.dharmanitech.com/2009/01/sd-card-interfacing-with-atmega8-fat32.html