Ser25lcxxx.h

00001 /*
00002 * Ser25lcxxx library
00003 * Copyright (c) 2010 Hendrik Lipka
00004 * 
00005 * Permission is hereby granted, free of charge, to any person obtaining a copy
00006 * of this software and associated documentation files (the "Software"), to deal
00007 * in the Software without restriction, including without limitation the rights
00008 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00009 * copies of the Software, and to permit persons to whom the Software is
00010 * furnished to do so, subject to the following conditions:
00011 * 
00012 * The above copyright notice and this permission notice shall be included in
00013 * all copies or substantial portions of the Software.
00014 * 
00015 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00016 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00017 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00018 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00019 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00020 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00021 * THE SOFTWARE.
00022 */
00023 
00024 #ifndef __SER25LCXXX_H__
00025 #define __SER25LCXXX_H__
00026 
00027 #include "mbed.h"
00028 
00029 /**
00030 A class to read and write all 25* serial SPI eeprom devices from Microchip (from 25xx010 to 25xx1024).
00031 
00032 One needs to provide total size and page size, since this cannot be read from the devices,
00033 and the page size differs even by constant size (look up the data sheet for your part!)
00034 */
00035 class Ser25LCxxx
00036 {
00037     public:
00038         /**
00039             create the handler class
00040             @param spi the SPI port where the eeprom is connected. Must be set to format(8,3), and with a speed matching the one of your device (up to 5MHz should work)
00041             @param enable the pin name for the port where /CS is connected
00042             @param bytes the size of you eeprom in bytes (NOT bits, eg. a 25LC010 has 128 bytes)
00043             @param pagesize the size of a single page, to provide overruns
00044         */
00045         Ser25LCxxx(SPI *spi, PinName enable, uint32_t bytes, uint32_t pagesize);
00046         
00047         /**
00048             destroys the handler, and frees the /CS pin        
00049         */
00050         ~Ser25LCxxx();
00051         
00052         /**
00053             read a part of the eeproms memory. The buffer will be allocated here, and must be freed by the user
00054             @param startAdr the adress where to start reading. Doesn't need to match a page boundary
00055             @param len the number of bytes to read (must not exceed the end of memory)
00056             @return NULL if the adresses are out of range, the pointer to the data otherwise
00057         */
00058         uint8_t* read( uint32_t startAdr,  uint32_t len);
00059         
00060         /**
00061             writes the give buffer into the memory. This function handles dividing the write into 
00062             pages, and waites until the phyiscal write has finished
00063             @param startAdr the adress where to start writing. Doesn't need to match a page boundary
00064             @param len the number of bytes to read (must not exceed the end of memory)
00065             @return false if the adresses are out of range
00066         */
00067         bool write( uint32_t startAdr,  uint32_t len, const uint8_t* data);
00068         
00069         /**
00070             fills the given page with 0xFF
00071             @param pageNum the page number to clear
00072             @return if the pageNum is out of range        
00073         */
00074         bool clearPage( uint32_t pageNum);
00075         
00076         /**
00077             fills the while eeprom with 0xFF
00078         */
00079         void clearMem();
00080     private:
00081         bool writePage( uint32_t startAdr,  uint32_t len, const uint8_t* data);
00082         uint8_t readStatus();
00083         void waitForWrite();
00084         void enableWrite();
00085         
00086 
00087         SPI* _spi;
00088         DigitalOut* _enable;
00089         uint32_t _size,_pageSize;
00090         
00091 };
00092 
00093 
00094 
00095 #endif