Diff: MCP23S17.h

Revision:

0:574e155464d5

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MCP23S17.h	Wed Jan 28 04:08:50 2015 +0000
@@ -0,0 +1,59 @@
+/* MCP23S17 - drive the Microchip MCP23S17 16-bit Port Extender using SPI
+* Copyright (c) 2010 Romilly Cocking
+* Released under the MIT License: http://mbed.org/license/mit
+*
+* version 0.4
+*/
+#include "mbed.h"
+
+#ifndef  MCP23S17_H
+#define  MCP23S17_H
+
+#define INTERRUPT_POLARITY_BIT 0x02
+#define INTERRUPT_MIRROR_BIT   0x40
+
+// all register addresses assume IOCON.BANK = 0 (POR default)
+
+#define IODIRA   0x00
+#define GPINTENA 0x04
+#define DEFVALA  0x06
+#define INTCONA  0x08
+#define IOCON    0x0A
+#define GPPUA    0x0C
+#define GPIOA    0x12
+#define OLATA    0x14
+
+// Control settings
+
+#define IOCON_BANK  0x80 // Banked registers
+#define IOCON_BYTE_MODE 0x20 // Disables sequential operation. If bank = 0, operations toggle between A and B registers
+#define IOCON_HAEN  0x08 // Hardware address enable
+
+enum Polarity { ACTIVE_LOW , ACTIVE_HIGH };
+enum Port { PORT_A, PORT_B };
+
+class MCP23S17 {
+public:
+    MCP23S17(SPI& spi, PinName ncs, char writeOpcode);
+    void direction(Port port, char direction);
+    void configurePullUps(Port port, char offOrOn);
+    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 interruptContolBits);
+    char read(Port port);
+    void write(Port port, char byte);
+protected:
+    SPI& _spi;
+    DigitalOut _ncs;
+    void _init();
+    void _write(Port port, char address, char data);
+    void _write(char address, char data);
+    char _read(Port port, char address);
+    char _read(char address);
+    char _readOpcode;
+    char _writeOpcode;
+};
+
+#endif
\ No newline at end of file