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Altera_Forum's avatar
Altera_Forum
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16 years ago

rbf header?

Hello,

I want to configure Cyclone II device via USB.

I already have a PIC18F2550 acting as a USB to JTAG converter. I am using it to configure Xilinx Spartan 2 FPGA.

I want to do the same thing for Cyclone II devices. For this, I need to know internals of configuration file format either rbf or some other file jbc for e.g. I don’t want all the details but only information about where exactly the configuration data starts and where it ends. I will send this data to my PIC18 over USB and PIC18 will control JTAG pins accordingly to configure the cyclone II device.

I read somewhere that rbf file contains 44 bytes of header. So if I skip first 44 bytes and send rest of the data over JTAG to the FPGA, will it work?

Any clue will be of very much help to me.

Thanking you in advance.

Regards,

Gopal

6 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    Did you notice the Altera JRUNNER project? It performs JTAG programming of SRAM based devices from a *.rbf file.

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    FvM,

    Thanks for the reply.

    I had gone through JRunner and noticed that header is first 44 bytes in the rbf file.

    So, if I skip first 44 bytes and send rest of the stream to FPGA in JTAG Shift IR state, will it work?

    I don't have yet the FPGA hardware ready and I want to study whether this project is possible or not.

    Thanks and regards,
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    rbf format is slightly different between devices. I see, that the most recent Jrunner version 2.3 has explicite support for Cyclone II and Cyclone III.

    --- Quote Start ---

    So, if I skip first 44 bytes and send rest of the stream to FPGA in JTAG Shift IR state, will it work?

    --- Quote End ---

    Hm. You send a device specific PROGRAM instruction in ShiftIR state and the configuration stream in ShiftDR. Check the JRunner software.
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    Oh yes, I meant Shift-DR state. It was a typo error.

    I should give a try with the rbf file by skipping first 44 bytes.

    I should also know that after the device is configured, if there is any particular sequence to be followed to make the device operational. Do you know that?

    Regards,
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    I never used embedded JTAG configuration. But with other configuration schemes, e.g. passiv serial, the user mode ist entered automaticly after succesful configuration. I would expect the same with JTAG configuration.

    The 44 Byte skip is specific to Cyclone and Cyclone II, as you can see from the recent JRunner software source.
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    Ok. Thanks for information. I will do some trial and error when I get the hardware.

    Regards,