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Altera_Forum's avatar
Altera_Forum
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15 years ago

Including own logic to sopc system

Hi,

I'm an altera-beginner working on a project to correct pixel-data on an FPGA (ep3c120 development board with cyclone3). Im sending 8-bit pixel-values from my pc with tcpip-packets which are received by a modified version of the simple socket server example, and the placed in SDRAM using the IOWR-function. So far so good! The board is configured with the standard hardware example from the CD.

Now I want to add some custom HDL logic to this system. The input to the logic is several 8-bit values, which will be used in some calculations and result in an output of one 8 bit value.

What is the easiest way to include my logic to the standard hardware example? I'm looking into the component editor in the sopc builder, but I'm finding it hard to understand which interfaces and signals I need to make it work.

I would like to be able to write data (IOWR) to my component from a C-program running on Nios, and read (IORD) the result back.

Any thought, hints or ideas are greatly appreciated.

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    If you want to use IOWR and IORD, the simpliest way to add Microcontroller peripherial to you NIOS system in SOPC editor. I think you better to use unidirectional ports, so input or output only. Good idea to utilize the interrupt system of NIOS at IORD.

    Another way is to create your own components using Avalon MM slave and master interfaces. Templates are available in the menu of Component Editor. In this case you will need to apply conduits too, so after you added your Avalon MM interfaces, add a CONDUIT too, and create the signals for this interface too. A simple example.

    You have one Avalon MM slave interface with 32 bit wide data signal input, then create a conduit interface too, then a conduit signal same wide as your data, but as output. After you succesfully built your NIOS you will see the pins of this conduit in the schematic diagram.

    Do not forget to always add the handshaking signals too, like ready, dataavailable, waitrequest, etc. Anyway, Component Editor will make noise to you if any HS signal is missing.
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    There should be some free WEB training on the altera site for learning this process. adding SoPC components.

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Thanks for the replies guys. I will probably be back with some more questions soon, but first I need to do some more reading on the Avalon interfaces etc to get a better understanding. I've checked out the web-training before, but I will do it again, more closely.