aaspi_eeprom.c

Aardvark Example Source Code Version: 4.00 Date: 2007-04-20 Source code which shows how to use the

/*=========================================================================
| (c) 2004-2007  Total Phase, Inc.
|--------------------------------------------------------------------------
| Project : Aardvark Sample Code
| File    : aaspi_eeprom.c
|--------------------------------------------------------------------------
| Perform simple read and write operations to an SPI EEPROM device.
|--------------------------------------------------------------------------
| Redistribution and use of this file in source and binary forms, with
| or without modification, are permitted.
|
| THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
| "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
| LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
| FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
| COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
| INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
| BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
| LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
| CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
| LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
| ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
| POSSIBILITY OF SUCH DAMAGE.
 ========================================================================*/

//=========================================================================
// INCLUDES
//=========================================================================
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "aardvark.h"


//=========================================================================
// CONSTANTS
//=========================================================================
#define PAGE_SIZE 32


//=========================================================================
// FUNCTIONS
//=========================================================================
static void _writeMemory (Aardvark handle, u16 addr, u16 length, int zero)
{
    u16 i, n;

    u08 data_out[3+PAGE_SIZE];
    u08 data_in[3+PAGE_SIZE];
    
    // Write to the SPI EEPROM
    // 
    // The AT25080A EEPROM has 32 byte pages.  Data can written
    // in pages, to reduce the number of overall SPI transactions
    // executed through the Aardvark adapter.
    n = 0;
    while (n < length) {
        // Send write enable command
        data_out[0] = 0x06;
        aa_spi_write(handle, 1, data_out, data_in);

        // Assemble write command and address
        data_out[0] = 0x02;
        data_out[1] = (addr >> 8) & 0xff;
        data_out[2] = (addr >> 0) & 0xff;
        
        // Assemble a page of data
        i = 3;
        do {
            data_out[i++] = zero ? 0 : (u08) n;
            ++addr; ++n;
        } while ( n < length && (addr & (PAGE_SIZE-1)) );

        // Write the transaction
        aa_spi_write(handle, i, data_out, data_in);
        aa_sleep_ms(10);
    }
}


static void _readMemory (Aardvark handle, u16 addr, u16 length)
{
    int count;
    int i;

    u08 *data_out  = (u08 *)malloc(length+3);
    u08 *data_in   = (u08 *)malloc(length+3);
    
    memset(data_out, 0, length+3);
    memset(data_in,  0, length+3);

    // Assemble read command and address
    data_out[0] = 0x03;
    data_out[1] = (addr >> 8) & 0xff;
    data_out[2] = (addr >> 0) & 0xff;

    // Write length+3 bytes for data plus command and 2 address bytes
    count = aa_spi_write(handle, (u16)(length+3), data_out, data_in);

    if (count < 0) {
        printf("error: %s\n", aa_status_string(count));
    }
    else if (count != length+3) {
        printf("error: read %d bytes (expected %d)\n", count-3, length);
    }

    // Dump the data to the screen
    printf("\nData read from device:");
    for (i=0; i < length; ++i) {
        if ((i&0x0f) == 0)      printf("\n%04x:  ", addr+i);
        printf("%02x ", data_in[i+3] & 0xff);
        if (((i+1)&0x07) == 0)  printf(" ");
    }
    printf("\n");

    // Free the packet
    free(data_out);
    free(data_in);
}


//=========================================================================
// MAIN PROGRAM
//=========================================================================
int main (int argc, char *argv[]) {
    Aardvark handle;
    int port    = 0;
    int bitrate = 100;
    int mode    = 0;
    u16 addr;
    u16 length;

    const char *command;

    if (argc < 7) {
        printf("usage: aaspi_eeprom PORT BITRATE read  MODE ADDR LENGTH\n");
        printf("usage: aaspi_eeprom PORT BITRATE write MODE ADDR LENGTH\n");
        printf("usage: aaspi_eeprom PORT BITRATE zero  MODE ADDR LENGTH\n");
        printf("  mode 0 : pol = 0, phase = 0\n");
        printf("  mode 3 : pol = 1, phase = 1\n");
        printf("  modes 1 and 2 are not supported\n");
        return 1;
    }

    port    = atoi(argv[1]);
    bitrate = atoi(argv[2]);
    command = argv[3];
    mode    = atoi(argv[4]);
    addr    = (unsigned short)strtol(argv[5], 0, 0);
    length  = atoi(argv[6]);
    
    if (mode == 1 || mode == 2) {
        printf("error: spi modes 1 and 2 are not supported by the AT25080A\n");
        return 1;
    }

    // Open the device
    handle = aa_open(port);
    if (handle <= 0) {
        printf("Unable to open Aardvark device on port %d\n", port);
        printf("Error code = %d\n", handle);
        return 1;
    }

    // Ensure that the SPI subsystem is enabled.
    aa_configure(handle, AA_CONFIG_SPI_I2C);
    
    // Power the EEPROM using the Aardvark adapter's power supply.
    // This command is only effective on v2.0 hardware or greater.
    // The power pins on the v1.02 hardware are not enabled by default.
    //aa_target_power(handle, AA_TARGET_POWER_BOTH);
    aa_target_power(handle, AA_TARGET_POWER_BOTH);
    
    // Setup the clock phase
    aa_spi_configure(handle, mode >> 1, mode & 1, AA_SPI_BITORDER_MSB);
    
    // Set the bitrate
    bitrate = aa_spi_bitrate(handle, bitrate);
    printf("Bitrate set to %d kHz\n", bitrate);

    // Perform the operation
    if (strcmp(command, "write") == 0) {
        _writeMemory(handle, addr, length, 0);
        printf("Wrote to EEPROM\n");
    }
    else if (strcmp(command, "read") == 0) {
        _readMemory(handle, addr, length);
    }
    else if (strcmp(command, "zero") == 0) {
        _writeMemory(handle, addr, length, 1);
        printf("Zeroed EEPROM\n");
    }
    else {
        printf("unknown command: %s\n", command);
    }

    // Close the device
    aa_close(handle);

    return 0;
}