Diff: MCP23017.h

Revision:

33:24ce12dec157

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MCP23017.h	Wed Jun 13 12:02:48 2018 +0000
@@ -0,0 +1,170 @@
+/* MCP23017 - drive the Microchip MCP23017 16-bit Port Extender using I2C
+* Copyright (c) 2010 Wim Huiskamp, Romilly Cocking (original version for SPI)
+*
+* Changed by Jacco van Splunter:
+* The _read and _write functions are moved from protected -> public
+*
+* Released under the MIT License: http://mbed.org/license/mit
+*
+* version 0.2 Initial Release
+* version 0.3 Cleaned up
+* version 0.4 Fixed problem with _read method
+* version 0.5 Added support for 'Banked' access to registers
+*/
+#include "mbed.h"
+
+#ifndef  MCP23017_H
+#define  MCP23017_H
+
+// All register addresses assume IOCON.BANK = 0 (POR default)
+#define IODIRA   0x00
+#define IODIRB   0x01
+#define IPOLA    0x02
+#define IPOLB    0x03
+#define GPINTENA 0x04
+#define GPINTENB 0x05
+#define DEFVALA  0x06
+#define DEFVALB  0x07
+#define INTCONA  0x08
+#define INTCONB  0x09
+#define IOCONA   0x0A
+#define IOCONB   0x0B
+#define GPPUA    0x0C
+#define GPPUB    0x0D
+#define INTFA    0x0E
+#define INTFB    0x0F
+#define INTCAPA  0x10
+#define INTCAPB  0x11
+#define GPIOA    0x12
+#define GPIOB    0x13
+#define OLATA    0x14
+#define OLATB    0x15
+
+// The following register addresses assume IOCON.BANK = 1 
+#define IODIRA_BNK   0x00
+#define IPOLA_BNK    0x01
+#define GPINTENA_BNK 0x02
+#define DEFVALA_BNK  0x03
+#define INTCONA_BNK  0x04
+#define IOCONA_BNK   0x05
+#define GPPUA_BNK    0x06
+#define INTFA_BNK    0x07
+#define INTCAPA_BNK  0x08
+#define GPIOA_BNK    0x09
+#define OLATA_BNK    0x0A
+
+#define IODIRB_BNK   0x10
+#define IPOLB_BNK    0x11
+#define GPINTENB_BNK 0x12
+#define DEFVALB_BNK  0x13
+#define INTCONB_BNK  0x14
+#define IOCONB_BNK   0x15
+#define GPPUB_BNK    0x16
+#define INTFB_BNK    0x17
+#define INTCAPB_BNK  0x18
+#define GPIOB_BNK    0x19
+#define OLATB_BNK    0x1A
+
+// This array allows structured access to Port_A and Port_B registers for both bankModes
+const int IODIR_AB[2][2]   = {{IODIRA, IODIRB},     {IODIRA_BNK, IODIRB_BNK}};
+const int IPOL_AB[2][2]    = {{IPOLA, IPOLB},       {IPOLA_BNK, IPOLB_BNK}};
+const int GPINTEN_AB[2][2] = {{GPINTENA, GPINTENB}, {GPINTENA_BNK, GPINTENB_BNK}};
+const int DEFVAL_AB[2][2]  = {{DEFVALA, DEFVALB},   {DEFVALA_BNK, DEFVALB_BNK}};
+const int INTCON_AB[2][2]  = {{INTCONA, INTCONB},   {INTCONA_BNK, INTCONB_BNK}};
+const int IOCON_AB[2][2]   = {{IOCONA, IOCONB},     {IOCONA_BNK, IOCONB_BNK}};
+const int GPPU_AB[2][2]    = {{GPPUA, GPPUB},       {GPPUA_BNK, GPPUB_BNK}};
+const int INTF_AB[2][2]    = {{INTFA, INTFB},       {INTFA_BNK, INTFB_BNK}};
+const int INTCAP_AB[2][2]  = {{INTCAPA, INTCAPB},   {INTCAPA_BNK, INTCAPB_BNK}};
+const int GPIO_AB[2][2]    = {{GPIOA, GPIOB},       {GPIOA_BNK, GPIOB_BNK}};
+const int OLAT_AB[2][2]    = {{OLATA, OLATB},       {OLATA_BNK, OLATB_BNK}};
+
+
+// Control settings
+#define IOCON_BANK      0x80 // Banked registers for Port A and B
+#define IOCON_BYTE_MODE 0x20 // Disables sequential operation, Address Ptr does not increment
+                             //   If Disabled and Bank = 0, operations toggle between Port A and B registers
+                             //   If Disabled and Bank = 1, operations do not increment registeraddress                             
+#define IOCON_HAEN      0x08 // Hardware address enable
+
+#define INTERRUPT_POLARITY_BIT 0x02
+#define INTERRUPT_MIRROR_BIT   0x40
+
+#define PORT_DIR_OUT   0x00
+#define PORT_DIR_IN    0xFF
+
+enum Polarity { ACTIVE_LOW , ACTIVE_HIGH };
+enum Port { PORT_A=0, PORT_B=1 };
+enum Bank { NOT_BNK=0, BNK=1 };
+
+class MCP23017 {
+public:
+    /** Create an MCP23017 object connected to the specified I2C object and using the specified deviceAddress
+    *
+    * @param I2C &i2c the I2C port to connect to 
+    * @param char deviceAddress the address of the MCP23017
+    */
+    MCP23017(I2C &i2c, char deviceAddress);
+
+    /** Set I/O direction of specified MCP23017 Port
+    *
+    * @param Port Port address (Port_A or Port_B)
+    * @param char direction pin direction (0 = output, 1 = input)
+    */
+    void direction(Port port, char direction);
+
+    /** Set Pull-Up Resistors on specified MCP23017 Port
+    *
+    * @param Port Port address (Port_A or Port_B)
+    * @param char offOrOn per pin (0 = off, 1 = on)
+    */    
+    void configurePullUps(Port port, char offOrOn);
+
+    void configureBanked(Bank bankmode);  
+    void interruptEnable(Port port, char interruptsEnabledMask);
+    void interruptPolarity(Polarity polarity);
+    void mirrorInterrupts(bool mirror);
+    void defaultValue(Port port, char valuesToCompare);
+    void interruptControl(Port port, char interruptControlBits);
+
+    /** Read from specified MCP23017 Port
+    *
+    * @param Port Port address (Port_A or Port_B)
+    * @returns data from Port 
+    */
+    char read(Port port);
+    
+    /** Write to specified MCP23017 Port
+    *
+    * @param Port Port address (Port_A or Port_B)
+    * @param char byte data to write
+    */    
+    void write(Port port, char byte);
+    
+    /** Write to specified MCP23017 register
+    *
+    * @param char address the internal registeraddress of the MCP23017
+    */
+    void _write(char address, char byte);
+
+    /** Read from specified MCP23017 register
+    *
+    * @param char address the internal registeraddress of the MCP23017
+    * @returns data from register 
+    */
+    char _read(char address);
+
+protected:
+    I2C &_i2c;
+    char _readOpcode;
+    char _writeOpcode;
+    Bank _bankMode; 
+    
+    /** Init MCP23017
+    *
+    * @param
+    * @returns 
+    */    
+    void _init();
+};
+
+#endif