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Altera_Forum's avatar
Altera_Forum
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15 years ago

DE1 with SD-card reader

Hello,

I would like to use the SD-card reader on the DE1 development board in order to store pictures that I want to display on a screen, through the VGA connector.

I already create a VGA synchronisation module and I am able to display dummy pattern on a VGA screen. But to make my tests more interesting I would like to load a picture from the SD-card and display it on the screen.

I made some research about using this SD card connector and what is weird is that on the DE1 user manual, the pin assignment to this connector are not explained (there is only a small schematics on the DE1 schematics). It is only said that it can be used....for example to store music to do a karaoké machine!!!!

I understood that SD card are using 4-pin SPI communication protocol and then I just want to retrieve a picture data to display it.

Then I need help/advices/hints to understand how to interpret the data from the SD-Card and how to get the picture information and to convert it (I guess CODEC are needed somewhere) before sending it to the VGA in order to display it.

Thank you in advance,

Meach

5 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    This is one of the example test programs that comes with the DE1 kit.

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    For SD card connection picture you can simply Google with "SD card pinout".

    Implementing a simple SD card controller is not difficult.

    You need a SPI master port and a sofware driver which manages the SD protocol.

    Download the SD card specification from www.sdcard.org (the simplified specification is enough)

    Read it and implement the required commands in your driver.

    Good luck

    Regards
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    @eviltwinzzz: yes I know but with those examples, you do not have access to the design files so it's not useful for me.

    @Cris72: I also found the connection in the schematics on the development board but then once I retrieve the picture stored on this SD-card (if I succeed to do it :-) ), how can I display it on the screen? Do you know if there is a sort of IP to do that or should I just look at the characteristic of bmp image for ex to get the pixels informations?

    I guess I will have some reading to do today then :)
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    --- Quote Start ---

    ... once I retrieve the picture stored on this SD-card (if I succeed to do it :-) ), how can I display it on the screen? Do you know if there is a sort of IP to do that or should I just look at the characteristic of bmp image for ex to get the pixels informations?

    --- Quote End ---

    I think that the more difficult part is to build everything for reading the bmp file from SD card. Then the road is downhill.

    Infact, getting the pixel information from bmp file is rather simple (see for example http://en.wikipedia.org/wiki/bmp_file_format). I'm assuming you already have the VGA display driver, so you simply have to turn on the required image pixels.

    I'm also assuming you are planning to use Nios or other processor to handle all the stuff.

    Cris
  • Altera_Forum's avatar
    Altera_Forum
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    9 years ago

    i do project on sd card interface.but can't that thing.can u help me?

    can you explain how to interface and using qsys or anyway.

    please give me information step by step.

    send this email: dipakj.chavada@gmail.com