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Altera_Forum's avatar
Altera_Forum
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20 years ago

How to use

i m using alt_avalon_spi_command() now, and i did it according to Altera Embedded Peripherals Handbook chapter 7. I m looking using SPI to transfer some data to another board. And i can't figure out how to use this command line.

int alt_avalon_spi_command(alt_u32 base, alt_u32 slave,

alt_u32 write_length, const alt_u8* wdata, alt_u32 read_length,

alt_u8* read_data, alt_u32 flags)

1) Where can i find what value i should put for alt_u32 slave?

2) What value should i put for flag?

3) If i m going to just send the data, in MOSI mode, what value should i put for read_length and read_data?

4) do you have an example demostrating how to use this command ?

I just can't get it to work on Nios II cyclone board.

how is i wrote the code

_______________________________________________________

/*

alt_u8 sending[16] = {

0x81, 0xCF, 0x92, 0x86, 0xCC, 0xA4, 0xA0, 0x8F, 0x80, 0x84,

0x88, 0xE0, 0xF2, 0xC2, 0xB0, 0xB8 };

alt_u8 receiving[16];

download= alt_avalon_spi_command(0x00800000,1,16, sending,16, receiving,1);

_______________________________________________________

and the output has no signal coming out. I can't figure out anything goes wrong.

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    20 years ago

    --- Quote Start ---

    originally posted by wei_chen0428@Mar 14 2006, 05:06 AM

    int alt_avalon_spi_command(alt_u32 base, alt_u32 slave,

    alt_u32 write_length, const alt_u8* wdata, alt_u32 read_length,

    alt_u8* read_data, alt_u32 flags)

    1) where can i find what value i should put for alt_u32 slave?

    2) what value should i put for flag?

    3) if i m going to just send the data, in mosi mode, what value should i put for read_length and read_data?

    4) do you have an example demostrating how to use this command ?

    <div align='right'><{post_snapback}> (index.php?act=findpost&pid=13399)

    --- quote end ---

    --- Quote End ---

    May You see source code of "altera_avalon_spi.c" ?

    If you can do it you can find out function alt_avalon_spi_command.

    And see all information about this function and its variables.

    I recommend you read manual about SPI in SOPC builder
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    20 years ago

    --- Quote Start ---

    originally posted by wei_chen0428@Mar 14 2006, 05:06 AM

    int alt_avalon_spi_command(alt_u32 base, alt_u32 slave,

    alt_u32 write_length, const alt_u8* wdata, alt_u32 read_length,

    alt_u8* read_data, alt_u32 flags)

    1) where can i find what value i should put for alt_u32 slave?

    2) what value should i put for flag?

    3) if i m going to just send the data, in mosi mode, what value should i put for read_length and read_data?

    4) do you have an example demostrating how to use this command ?

    <div align='right'><{post_snapback}> (index.php?act=findpost&pid=13399)

    --- quote end ---

    --- Quote End ---

    1. alt_u32 slave is the number of slave connected to your master, with the first one starting from "0", as pointed out in the documentation.

    2. Flag = ALT_AVALON_SPI_COMMAND_MERGE, if you wish to use that function, else put 0.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    11 years ago

    --- Quote Start ---

    [/b]

    --- Quote End ---

    1. alt_u32 slave is the number of slave connected to your master, with the first one starting from "0", as pointed out in the documentation.

    So if I have 4 slaves connected to the SPI master, I should set slave =0x03? I think this argument is used to select which slave I want to write or read, e.g.: if I want to read or write slave 0, I should set slave = 0x00, correct?

    Thanks.