main.cpp

00001 /*
00002   Hotboards eeprom Library - write_byte
00003  Demonstrates the use a spi eeprom. The Hotboards_eeprom
00004  library works with all Microchip 25xxx serial memory series 
00005  like the one presented eeprom board (http://www.hotboards.org).
00006  This sketch read a single byte into a variable, then, the variable is added by two,
00007  the result is written into memory. Finally, byte is readed again.
00008  the values are printed to serial port too.
00009  
00010  The circuit:
00011  *  VDD   -->  3.3v
00012  *  SO    -->  PB_14
00013  *  SI    -->  PB_15
00014  *  SCK   -->  PB_13
00015  *  CS    -->  PC_4
00016  *  GND   -->  GND
00017  
00018  Library  created by Diego from Hotboards
00019  example added by Pedro from Hotboards
00020  */
00021  
00022 #include "mbed.h"
00023 #include "Hotboards_eeprom.h"
00024 
00025 /*Open an instance of serial port*/
00026 Serial pc(USBTX,USBRX);
00027 /* initialize an instance of SPI bus,setting the SPI pins*/
00028 SPI device(PB_15,PB_14,PB_13); /* SO, SI, SCK*/  
00029 /*initialize the library with the numbers of the interface pins*/
00030 Hotboards_eeprom eeprom(device,PC_4,HT_EEPROM25xx_32Kb); /* (spi,Cs,Density) */
00031 
00032 int main() 
00033 {
00034     /*SPI transfer at 8 bits, MODE = 3*/
00035     device.format(8,3);
00036     /* set the spi frequency to 5MHz  */
00037     device.frequency(5000000);
00038     /*initialize CS pin*/
00039     eeprom.init();
00040     
00041     /* variable to read data*/
00042     char Data;
00043     
00044     /* read firts byte*/
00045     Data=eeprom.read(0);
00046     /* send to serial port*/
00047     printf("%X \n",Data); 
00048     
00049     /* readed data is added by two */
00050     Data+= 2;
00051     /* write the result*/
00052     eeprom.write(0,Data);
00053     
00054     /* read firts byte again*/
00055     Data=eeprom.read(0);
00056     /* send to serial port */
00057     printf("%X \n",Data); 
00058     
00059     while(1)
00060     {
00061         /*loop*/
00062     }
00063     
00064 }