Diff: MCP23017.h

Revision:

0:6dd30d790eff

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MCP23017.h	Mon Jun 02 05:38:36 2014 +0000
@@ -0,0 +1,204 @@
+/* MCP23017 Library for mbed
+ * Copyright (c) 2014, Takuya Urakawa
+ * 
+ * This library is released under the MIT License
+ * See http://opensource.org/licenses/mit-license.php
+ */
+
+#ifndef _MCP23017_H_
+#define _MCP23017_H_
+
+#include "mbed.h"
+
+/** \def usefull defines */
+#define MCP23017_DEFAULT_ADDR 0x40
+#define MCP23017_PORTA 0x00
+#define MCP23017_PORTB 0x01
+
+namespace MCP23017 {	
+	
+/** MCP23017 class
+ *
+ *	Allow access MCP23017 I2C 16bit io expander IC
+ *  But this library can not controll interrupt functions
+ *
+ *  Example:
+ *  @code
+ *  #include "mbed.h"
+ *  #include "MCP23017.h"
+ *
+ *  I2C i2c(dp5, dp27); // LPC1114
+ *  MCP23017::MCP23017 io(&i2c,MCP23017_DEFAULT_ADDR);
+ *
+ *  int main(void)
+ *  {	
+ *	  i2c.frequency(400000);
+ *	
+ *	  // software reset
+ *	  io.init();
+ *	
+ *	  io.setDirrection(MCP23017_PORTA, 0xFF);    // set all of the PORTA pins to input
+ *	  io.setDirrection(MCP23017_PORTB, 0x00);    // set all of the PORTB pins to output
+ *	  io.setPullUp(MCP23017_PORTA, 0xFF);        // activate all of the PORTA pin pull-ups
+ *	  io.setInputPolarity(MCP23017_PORTA, 0xFF); // invert all of the PORTA pins input polarity
+ *
+ *    while(true){
+ *	  	// write PORTA to PORTB
+ *  	io.write(1,io.read(0));
+ *	  }
+ *
+ *	  return 0;
+ *  }
+ *  @endcode
+ */
+class MCP23017{
+public:
+	
+	/** Constructor
+	 *
+	 *  @param _i2c   pointer to I2C class
+	 *  @param _addr  i2c device address
+	 */
+    MCP23017(I2C &_i2c, char _addr);
+
+	/** Software Reset
+	 */
+	void init(void);
+
+	/** Configure MCP23017 
+	 *  Write IOCON register
+	 *  See MCP23017 datasheet p18
+	 *  http://ww1.microchip.com/downloads/jp/DeviceDoc/21952b.pdf
+	 *  
+	 *  @attention BANK bit must set 0
+	 *  
+	 *  @param _value  write byte  
+	 */
+	void setConfig(char _value);
+
+	/** Set I/O dirrection
+	 *  
+	 *  @param _port   port(MCP23017_PORTA or MCP23017_PORTB)
+	 *  @param _value  write byte(0=OUTPUT, 1=INPUT)
+	 */
+	void setDirrection(char _port, char _value);
+	
+	/** Set pullup
+	 *  
+	 *  @param _port   port (MCP23017_PORTA or MCP23017_PORTB)
+	 *  @param _value  write byte (0=Disable, 1=Enable)
+	 */
+	void setPullUp(char _port, char _value);
+	
+	/** Set Input Polarity
+	 *  
+	 *  @param _port   port(MCP23017_PORTA or MCP23017_PORTB)
+	 *  @param _value  write byte (0=normal, 1=inverted)
+	 */
+	void setInputPolarity(char _port, char _value);
+	
+	/** Write GPIO
+	 *
+	 *  @param _port   port(MCP23017_PORTA or MCP23017_PORTB)
+	 *  @param _value  write byte 
+	 */
+	void write(char _port, char _value);
+	
+	/** Read GPIO
+	 *
+	 *  @param _port   port(MCP23017_PORTA or MCP23017_PORTB)
+	 *  @return        byte
+	 */
+	char read(char _port);
+	
+	
+	// void setInterruptConfig(char _port, char _intcon, char _defval);
+	// void interrupt(char _port, char _value);
+	// char readIntcap(char _port);
+
+
+private:
+    I2C  &mI2c;
+	char mWriteAddr;
+	char mReadAddr;
+
+
+	inline void i2cSend(char _command, char _data1, char _data2){
+		char commands[3];
+		commands[0] = _command;
+		commands[1] = _data1;
+		commands[2] = _data2;
+
+		mI2c.write(mWriteAddr, commands, 3);
+	}
+	
+	inline void i2cSend(char _command, char _data1){
+		char commands[2];
+		commands[0] = _command;
+		commands[1] = _data1;
+		
+		mI2c.write(mWriteAddr, commands, 2);
+	}
+	
+	inline char i2cRead(char _command){
+		char commands[2];
+		commands[0] = _command;
+		mI2c.write(mWriteAddr, commands, 1);
+		//return (char)mI2c->read(0);
+		mI2c.read(mReadAddr,commands,1);
+		return commands[0];
+	}
+	
+	
+	// registors
+	enum MCP23017_REG {
+		// IO Dirrection
+		REG_IODIR = 0x00,
+
+		// Input polarity
+		REG_IPOL = 0x02,
+
+		// Interrupt-On-Change enable
+		REG_GPINTEN = 0x04,
+
+		// Default intterupt comparison value
+		// Refer to INTCON
+		REG_DEFVAL = 0x06,
+
+		// Intterupt compare value
+		// 1 = compare against DEFVAL value
+		// 0 = compare against the previous value
+		REG_INTCON = 0x08,
+
+		// IC setting
+		// bank/mirror/seqop/disslw/haen/odr/intpol/notimp
+		// must be set bank = 0 for using this library
+		// See MCP23017 datasheet
+		REG_IOCON = 0x0A,
+
+		// Pullup
+		REG_GPPU = 0x0C,
+
+		// Interrupt Flag
+		// 1 = pin caused interrupt
+		// 0 = no interrupt 
+		// Read-Only
+		REG_INTF = 0x0E,
+
+		// Interrupt capture
+		// value of GPIO at time of last interrupt
+		// Read-Only
+		REG_INTCAP = 0x10,
+
+		// GPIO
+		REG_GPIO = 0x12,
+
+		// Output Latch
+		REG_OLAT = 0x14
+	};
+	
+}; // end of class
+}; // end of namespace
+
+#endif
+