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Altera_Forum's avatar
Altera_Forum
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17 years ago

Problem PIO

Hello to all,

I'm new in FPGA and I have a Cyclone II and I made a design with a Nios II.

I just want to drive a component (LM629) and I have to send et receive data.

I created a tri state PIO

# define LM629_DON_NAME "/dev/LM629_DON"

# define LM629_DON_TYPE "altera_avalon_pio"

# define LM629_DON_BASE 0x01000010

# define LM629_DON_SPAN 16

# define LM629_DON_DO_TEST_BENCH_WIRING 0

# define LM629_DON_DRIVEN_SIM_VALUE 0x0000

# define LM629_DON_HAS_TRI 1

# define LM629_DON_HAS_OUT 0

# define LM629_DON_HAS_IN 0

# define LM629_DON_CAPTURE 0

# define LM629_DON_EDGE_TYPE "NONE"

# define LM629_DON_IRQ_TYPE "NONE"

# define LM629_DON_FREQ 85000000

# define ALT_MODULE_CLASS_LM629_DON altera_avalon_pio

To send a data I just write IOWR_ALTERA_AVALON_PIO_DATA(LM629_DON_BASE , mydata).... and the problem that it doesn't work, I can't send the data...

I read I have to change the direction of my port and I use IOWR_ALTERA_AVALON_PIO_DIRECTION(base, data)

But finally it's the same thing. :(

Can you help me ??

Thanks

7 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    did you get nios with an altera dev board? Look in the Examples directory within the kit install path for examples that use PIO.

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    Did you check the header file altera_avalon_pio_regs.h? There are several defines there that can be of interest:

    # define IOADDR_ALTERA_AVALON_PIO_DIRECTION(base) __IO_CALC_ADDRESS_NATIVE(base, 1)

    # define IORD_ALTERA_AVALON_PIO_DIRECTION(base) IORD(base, 1)

    # define IOWR_ALTERA_AVALON_PIO_DIRECTION(base, data) IOWR(base, 1, data)

    # define ALTERA_AVALON_PIO_DIRECTION_INPUT 0

    # define ALTERA_AVALON_PIO_DIRECTION_OUTPUT 1
  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    I have almost the same problem.

    I created a component in Qsys with 3 differently Conduits (sd_clk, sd_cmd and sd_dat) and for this component I have just one Base.

    How can I use the function IOWR_ALTERA_AVALON_PIO_DIRECTION(component_base, _____) to write output and input for each of the conduits?

    Does anyone have an idea?

    Thank a lot in advance!!!
  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    Those functions are only for Avalon interfaces. Conduits, by their nature, are interfaces that don't conform to a standard supported in Qsys, like Avalon. If you want to use those functions, you have to implement Avalon interfaces on your custom component.

  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    --- Quote Start ---

    Those functions are only for Avalon interfaces. Conduits, by their nature, are interfaces that don't conform to a standard supported in Qsys, like Avalon. If you want to use those functions, you have to implement Avalon interfaces on your custom component.

    --- Quote End ---

    But I implemented Avalon interface for my component. When I created my component in Qsys, the Avalon interface actually appeared automatically and I just added the three conduits to it.
  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    I don't understand. What are those conduits connected to? They are single signals, not Avalon interfaces, so you can't use the functions you mention except for that slave interface.

  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    --- Quote Start ---

    I don't understand. What are those conduits connected to? They are single signals, not Avalon interfaces, so you can't use the functions you mention except for that slave interface.

    --- Quote End ---

    These conduits are connected to the PINs of my FPGA board.

    I followed this tutorial: http://scale.engin.brown.edu/classes/en2911xf14/qsys_comp.pdf

    and did the creation of a new component exactly as the reg16_avalon_interface, the only diference was the three conduits and not just one.

    This tutorial doesn't show how to use the functions IOWR_ALTERA_AVALON_PIO_DIRECTION and IOWR_ALTERA_AVALON_PIO_DATA, but I understood that I could do like this:

    IOWR_ALTERA_AVALON_PIO_DATA(reg16_avalon_interface_base, 0xFFFF) and IOWR_ALTERA_AVALON_PIO_DATA will not be needed since to_hex (conduit) is an output.

    I think it would be the same in my case, but I don't know how to write it in these functions, since I have three conduits (sd_clk : out, sd_cmd : inout, sd_dat : inout) and one of them (sd_dat) is a std_logic_vector of size 4. That means I have 6 signals altogether.

    The tutorial shows how to make an avalon interface slave and uses it. But does not show how to use these functions in a software (Nios II Eclipse, which I am using).

    Is it really not possible to use these functions for my case?