update for ci test shield
Fork of I2CEeprom by
I2CEeprom.h
- Committer:
- rhourahane
- Date:
- 2015-07-19
- Revision:
- 1:b23f5561266c
File content as of revision 1:b23f5561266c:
/* Simple access class for I2C EEPROM chips like Microchip 24LC * Copyright (c) 2015 Robin Hourahane * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef __I2CEEPROM_H__ #define __I2CEEPROM_H__ #include <mbed.h> /// Class to provide simple access to I2C EEPROM chiles like Microchip's 24LC range /// or AMTELS AT24C range. /// Chips up to 64Kb in size are directly supported. /// The class handles multiple page writes so any amount of data can be written in /// a single call to write. The writes are not buffered so additional memory use /// is kept to a minimum. /// /// Although not tested it should work with the MAC versions of Microchip range /// as well but the chipSize will need to be set to include the ROM area as well. class I2CEeprom { public: /// Constructor to create a new instance of the class. /// @param sda The pin name for the sda line of the I2C bus. /// @param scl The pin name for the scl line of the I2C bus. /// @param address The 8bit I2C address of the chip in the range 0xA0 - 0xAE. /// @param pageSize The size of the page used in writing to the chip. /// @param chipSize The size of the memory in the chip to allow range checkng. Set to /// 0 to disable checks. /// @param busSpeed The frequency of the I2C bus defaults to 400K. I2CEeprom(PinName sda, PinName scl, int address, size_t pageSize, size_t chipSize, int busSpeed = 400000); /// Read a single byte from the address in memory. /// @param address Memory address to read from. /// @param value Variable to receive value read. /// @returns Number of bytes read from memory. size_t read(size_t address, char &value); /// Read multiple bytes starting from the address in memory. /// @param address Memory address to start reading from. /// @param buffer Pointer to buffer to hold bytes read from memory. /// @param size Number of bytes to be read from memory. /// @returns Number of bytes read from memory. size_t read(size_t address, char *buffer, size_t size); /// Read either an instance or an array of a POD type from memory. /// Note the value of the type can't contain pointers. /// @param address Start address for reading memory. /// @param value Object to be read from memory. /// @returns Number of bytes read from memory. template<typename T> size_t read(size_t address, T &value) { return read(address, reinterpret_cast<char *>(&value), sizeof(T)); } /// Write a single byte to the address in memory. /// @param address Memory address to write to. /// @param value Value to be written to memory. /// @returns Number of bytes written to memory. size_t write(size_t address, char value); /// Write multiple bytes starting from the address in memory. /// @param address Memory address to start writting to. /// @param buffer Pointer to buffer holding the bytes to write to memory. /// @param size Number of bytes to be written to memory. /// @returns Number of bytes written to memory. size_t write(size_t address, const char *buffer, size_t size); /// Write either an instance or an array of a POD type to memory. /// Note the value of the type can't contain pointers. /// @param address Start address to write to memory. /// @returns Number of bytes written to memory. template<typename T> size_t write(size_t address, const T &value) { return write(address, reinterpret_cast<const char *>(&value), sizeof(T)); } /// Fill a range of memory with a single value. No memory is allocated /// so large areas can be filled with minimal memory usage. /// @param address Starting address to write to. /// @param value Value to be written to memory. /// @Param size Number of bytes to be written. /// @returns Number of bytes written to memory. size_t fill(size_t address, char value, size_t size); private: // Wait for a write cycle to complete using polling and small waits. void waitForWrite(); // Validate that the proposed opperation will fit in the size of // the chip. bool checkSpace(size_t address, size_t size); private: I2C m_i2c; int m_i2cAddress; size_t m_chipSize; size_t m_pageSize; }; #endif