Storage.cpp

//
// Lucky Resistor's Deluxe Data Logger
// ---------------------------------------------------------------------------
// (c)2015 by Lucky Resistor. See LICENSE for details.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
//
#include "Storage.h"


#include <Wire.h>


namespace lr {
namespace Storage {


/// The address of the FRAM chip in the I2C bus.
///
/// The address is 1010AAA where AAA is the custom address which can
/// be set with the pins on the chip.
///
static const uint8_t cMb85RcAddress = B1010000;


bool begin()
{
    // Read the manufacturer ID and product ID to make sure the FRAM is available.
    Wire.beginTransmission(0xf8>>1);
    Wire.write(cMb85RcAddress<<1);
    Wire.endTransmission(false);
    Wire.requestFrom(0xf8>>1, 3);
    const uint8_t id0 = Wire.read();
    const uint8_t id1 = Wire.read();
    const uint8_t id2 = Wire.read();
    const uint16_t manufacturerID = (id0<<4)+(id1>>4);
    const uint16_t productID = ((id1&0x0f)<<8)+id2;
    // Check the both IDs
    if (manufacturerID != 0x00a || productID != 0x510) {
        return false;
    }
    return true;
}


uint32_t size()
{
    return 32768; // 32KB
}


void writeByte(uint32_t index, uint8_t data)
{
    Wire.beginTransmission(cMb85RcAddress);
    Wire.write(index>>8);
    Wire.write(index&0xff);
    Wire.write(data);
    Wire.endTransmission();
}


void writeBytes(uint32_t firstIndex, const uint8_t *data, uint32_t size)
{
    Wire.beginTransmission(cMb85RcAddress);
    Wire.write(static_cast<uint8_t>(firstIndex>>8));
    Wire.write(static_cast<uint8_t>(firstIndex&0xff));
    for (uint32_t i = 0; i < size; ++i) {
        Wire.write(data[i]);
    }
    Wire.endTransmission();
}


uint8_t readByte(uint32_t index)
{
    Wire.beginTransmission(cMb85RcAddress);
    Wire.write(static_cast<uint8_t>(index>>8));
    Wire.write(static_cast<uint8_t>(index&0xff));
    Wire.endTransmission();
    Wire.requestFrom(cMb85RcAddress, static_cast<uint8_t>(1));
    return Wire.read();
}


void readBytes(uint32_t firstIndex, uint8_t *data, uint32_t size)
{
    // reads >0xff will not work.
    Wire.beginTransmission(cMb85RcAddress);
    Wire.write(static_cast<uint8_t>(firstIndex>>8));
    Wire.write(static_cast<uint8_t>(firstIndex&0xff));
    Wire.endTransmission();
    Wire.requestFrom(cMb85RcAddress, static_cast<uint8_t>(size));
    for (uint32_t i = 0; i < size; ++i) {
        data[i] = Wire.read();
    }
}


}
}