Marine Electricals
16-Bit I/O Expander with Serial Interface (SPI)
Fork of
MCP23S17
by 
Steen Jørgensen
Diff: MCP23S17.h
- Revision:
- 2:b74bf9a31168
- Child:
- 4:029e24cc2b68
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/MCP23S17.h Tue Apr 21 16:20:23 2015 +0000
@@ -0,0 +1,513 @@
+/* mbed MCP23S17 Library, for driving the MCP23S17 16-Bit I/O Expander with Serial Interface (SPI)
+ * Copyright (c) 2015, Created by Steen Joergensen (stjo2809) inspired by Romilly Cocking MCP23S17 library
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "mbed.h"
+
+#ifndef MBED_MCP23S17_H
+#define MBED_MCP23S17_H
+
+//=============================================================================
+// All Registers and there Address if BANK = 0
+//=============================================================================
+
+#define IODIRA_ADDR 0x00 // Controls the direction of the data I/O on Port A
+#define IODIRB_ADDR 0x01 // Controls the direction of the data I/O on Port B
+#define IPOLA_ADDR 0x02 // Configure the polarity on the corresponding GPIO (Port A)
+#define IPOLB_ADDR 0x03 // Configure the polarity on the corresponding GPIO (Port B)
+#define GPINTENA_ADDR 0x04 // Controls the interrupt-on change feature for each pin for Port A
+#define GPINTENB_ADDR 0x05 // Controls the interrupt-on change feature for each pin for Port B
+#define DEFVALA_ADDR 0x06 // The default comparison value if the INTCONA is set to "1" for Port A
+#define DEFVALB_ADDR 0x07 // The default comparison value if the INTCONA is set to "1" for Port B
+#define INTCONA_ADDR 0x08 // Controls how the associated pin value is compared for the interrupt-on-change feature for Port A
+#define INTCONB_ADDR 0x09 // Controls how the associated pin value is compared for the interrupt-on-change feature for Port B
+#define IOCON_ADDR 0x0A // Contains several bits for configuring the device
+#define GPPUA_ADDR 0x0C // Controls the pull-up resistors for the port pins for port A
+#define GPPUB_ADDR 0x0D // Controls the pull-up resistors for the port pins for port B
+#define INTFA_ADDR 0x0E // READ ONLY // reflects the interrupt condition on port A pins of any pin that is enabled for interrupts via the GPINTEN register.
+#define INTFB_ADDR 0x0F // READ ONLY // reflects the interrupt condition on port B pins of any pin that is enabled for interrupts via the GPINTEN register.
+#define INTCAPA_ADDR 0x10 // READ ONLY // captures the GPIO port A value at the time the interrupt occurred
+#define INTCAPB_ADDR 0x11 // READ ONLY // captures the GPIO port B value at the time the interrupt occurred
+#define GPIOA_ADDR 0x12 // Reflects the value on the port A (doing write function it only read input)
+#define GPIOB_ADDR 0x13 // Reflects the value on the port B (doing write function it only read input)
+#define OLATA_ADDR 0x14 // A write to this register modifies the output latches that modifies the pins configured as outputs for Port A
+#define OLATB_ADDR 0x15 // A write to this register modifies the output latches that modifies the pins configured as outputs for Port B
+
+//=============================================================================
+// Declaration of variables & custom #defines
+//=============================================================================
+
+#define INTERRUPT_MIRROR_BIT 0x40
+#define INTERRUPT_POLARITY_BIT 0x02
+
+
+//=============================================================================
+// Functions Declaration
+//=============================================================================
+
+/** Interface to the MCP23S17 16-Bit I/O Expander with Serial Interface (SPI)
+ *
+ * Using the driver:
+ * - remenber to setup SPI in main routine.
+ * - remenber to setup interrupt pin or pins in main routine (if you are using interrupts).
+ *
+ * Defaults in this driver:
+ * - as default is hardware adressing "On" and if disable use "0" in hardwareaddress when creating the instance.
+ * - as default is interrupt pins "Active High".
+ * - as default is INTA is associated with PortA and INTB is associated with PortB.
+ *
+ * Limitations of using this driver:
+ * - can't use Open-Drain output.
+ * - can't use Sequential Operation mode bit.
+ * - can't use BANK 1 addressing.
+ *
+ */
+class MCP23S17 {
+public:
+ /** Create an instance of the MCP23S17 connected via specfied SPI instance, with the specified address.
+ *
+ * @param hardwareaddress The SPI hardware address 0-7 for this MCP23S17.
+ * @param spi The mbed SPI instance (make in main routine)
+ * @param nCs The SPI chip select pin.
+ * @param nReset The Hardware reset pin.
+ */
+ MCP23S17(int hardwareaddress, SPI& spi, PinName nCs, PinName nReset);
+
+ /** Create an instance of the MCP23S17 connected via specfied SPI instance, with the specified address, and Global reset only.
+ *
+ * @param hardwareaddress The SPI hardware address 0-7 for this MCP23S17.
+ * @param spi The mbed SPI instance (make in main routine)
+ * @param nCs The SPI chip select pin.
+ */
+ MCP23S17(int hardwareaddress, SPI& spi, PinName nCs);
+
+
+ /** Read an Register address.
+ *
+ * @param reg_address The selected register to read from.
+ * @return The 8 bits read, but if GPIO register only the value of the inputs (outputs is read as "0").
+ */
+ char read(char reg_address);
+
+ /** Write to Register address.
+ *
+ * @param reg_adress The selected register to write to.
+ * @param data The 8 bits to write to the register, but if GPIO only the output will change.
+ */
+ void write(char reg_address, char data);
+
+ /** Write to Bit in a register.
+ *
+ * @param reg_adress The selected register to write to.
+ * @param bit The bit with to write in, values from 1 to 8
+ * @param high_low The value to write the bit True = '1' and False = '0'.
+ */
+ void bit(char reg_address, int bitnumber, bool high_low);
+
+ /** Resetting the MCP23S17.
+ *
+ * Reset has to be pull down for min. 1uS to insure correct reset.
+ * This function pull down the reset pin for 5uS.
+ */
+ void reset();
+
+ /** Read IODIRA.
+ *
+ * I/O DIRECTION REGISTER
+ * Controls the direction of the data I/O.
+ *
+ * @return The 8 bits read.
+ */
+ char iodira();
+
+ /** Write to IODIRA.
+ *
+ * I/O DIRECTION REGISTER
+ * Controls the direction of the data I/O.
+ *
+ * @param data The 8 bits to write to IODIRA register.
+ */
+ void iodira(char data);
+
+ /** Read IODIRB.
+ *
+ * I/O DIRECTION REGISTER
+ * Controls the direction of the data I/O.
+ *
+ * @return The 8 bits read.
+ */
+ char iodirb();
+
+ /** Write to IODIRB.
+ *
+ * I/O DIRECTION REGISTER
+ * Controls the direction of the data I/O.
+ *
+ * @param data The 8 bits to write to IODIRB register.
+ */
+ void iodirb(char data);
+
+ /** Read IPOLA.
+ *
+ * INPUT POLARITY REGISTER
+ * This register allows the user to configure the polarity on the corresponding GPIO port bits.
+ *
+ * @return The 8 bits read.
+ */
+ char ipola();
+
+ /** Write to IPOLA.
+ *
+ * INPUT POLARITY REGISTER
+ * This register allows the user to configure the polarity on the corresponding GPIO port bits.
+ *
+ * @param data The 8 bits to write to IPOLA register.
+ */
+ void ipola(char data);
+
+ /** Read IPOLB.
+ *
+ * INPUT POLARITY REGISTER
+ * This register allows the user to configure the polarity on the corresponding GPIO port bits.
+ *
+ * @return The 8 bits read.
+ */
+ char ipolb();
+
+ /** Write to IPOLB.
+ *
+ * INPUT POLARITY REGISTER
+ * This register allows the user to configure the polarity on the corresponding GPIO port bits.
+ *
+ * @param data The 8 bits to write to IPOLB register.
+ */
+ void ipolb(char data);
+
+ /** Read GPINTENA.
+ *
+ * INTERRUPT-ON-CHANGE CONTROL REGISTER
+ * The GPINTEN register controls the interrupt-onchange feature for each pin.
+ *
+ * @return The 8 bits read.
+ */
+ char gpintena();
+
+ /** Write to GPINTENA.
+ *
+ * INTERRUPT-ON-CHANGE CONTROL REGISTER
+ * The GPINTEN register controls the interrupt-onchange feature for each pin.
+ *
+ * @param data The 8 bits to write to GPINTENA register.
+ */
+ void gpintena(char data);
+
+ /** Read GPINTENB.
+ *
+ * INTERRUPT-ON-CHANGE CONTROL REGISTER
+ * The GPINTEN register controls the interrupt-onchange feature for each pin.
+ *
+ * @return The 8 bits read.
+ */
+ char gpintenb();
+
+ /** Write to GPINTENB.
+ *
+ * INTERRUPT-ON-CHANGE CONTROL REGISTER
+ * The GPINTEN register controls the interrupt-onchange feature for each pin.
+ *
+ * @param data The 8 bits to write to GPINTENB register.
+ */
+ void gpintenb(char data);
+
+ /** Read DEFVALA.
+ *
+ * DEFAULT COMPARE REGISTER FOR INTERRUPT-ON-CHANGE
+ * The default comparison value is configured in the DEFVAL register, If enabled (via GPINTEN and INTCON).
+ *
+ * @return The 8 bits read.
+ */
+ char defvala();
+
+ /** Write to DEFVALA.
+ *
+ * DEFAULT COMPARE REGISTER FOR INTERRUPT-ON-CHANGE
+ * The default comparison value is configured in the DEFVAL register, If enabled (via GPINTEN and INTCON).
+ *
+ * @param data The 8 bits to write to DEVALA register.
+ */
+ void defvala(char data);
+
+ /** Read DEFVALB.
+ *
+ * DEFAULT COMPARE REGISTER FOR INTERRUPT-ON-CHANGE
+ * The default comparison value is configured in the DEFVAL register, If enabled (via GPINTEN and INTCON).
+ *
+ * @return The 8 bits read.
+ */
+ char defvalb();
+
+ /** Write to DEFVALB.
+ *
+ * DEFAULT COMPARE REGISTER FOR INTERRUPT-ON-CHANGE
+ * The default comparison value is configured in the DEFVAL register, If enabled (via GPINTEN and INTCON).
+ *
+ * @param data The 8 bits to write to DEVALB register.
+ */
+ void defvalb(char data);
+
+ /** Read INTCONA.
+ *
+ * INTERRUPT CONTROL REGISTER
+ * The INTCON register controls how the associated pin value is compared for the interrupt-on-change feature.
+ *
+ * @return The 8 bits read.
+ */
+ char intcona();
+
+ /** Write to INTCONA.
+ *
+ * INTERRUPT CONTROL REGISTER
+ * The INTCON register controls how the associated pin value is compared for the interrupt-on-change feature.
+ *
+ * @param data The 8 bits to write to INTCONA register.
+ */
+ void intcona(char data);
+
+ /** Read INTCONB.
+ *
+ * INTERRUPT CONTROL REGISTER
+ * The INTCON register controls how the associated pin value is compared for the interrupt-on-change feature.
+ *
+ * @return The 8 bits read.
+ */
+ char intconb();
+
+ /** Write to INTCONB.
+ *
+ * INTERRUPT CONTROL REGISTER
+ * The INTCON register controls how the associated pin value is compared for the interrupt-on-change feature.
+ *
+ * @param data The 8 bits to write to INTCONB register.
+ */
+ void intconb(char data);
+
+ /** Read IOCON.
+ *
+ * CONFIGURATION REGISTER
+ * The IOCON register contains several bits for configuring the device.
+ *
+ * @return The 8 bits read.
+ */
+ char iocon();
+
+ /** Write to IOCON.
+ *
+ * CONFIGURATION REGISTER
+ * The IOCON register contains several bits for configuring the device.
+ *
+ * @param data The 8 bits to write to IOCON register.
+ */
+ void iocon(char data);
+
+ /** Read GPPUA.
+ *
+ * PULL-UP RESISTOR CONFIGURATION REGISTER
+ * The GPPU register controls the pull-up resistors for the port pins.
+ *
+ * @return The 8 bits read.
+ */
+ char gppua();
+
+ /** Write to GPPUA.
+ *
+ * PULL-UP RESISTOR CONFIGURATION REGISTER
+ * The GPPU register controls the pull-up resistors for the port pins.
+ *
+ * @param data The 8 bits to write to GPPUA register.
+ */
+ void gppua(char data);
+
+ /** Read GPPUB.
+ *
+ * PULL-UP RESISTOR CONFIGURATION REGISTER
+ * The GPPU register controls the pull-up resistors for the port pins.
+ *
+ * @return The 8 bits read.
+ */
+ char gppub();
+
+ /** Write to GPPUB.
+ *
+ * PULL-UP RESISTOR CONFIGURATION REGISTER
+ * The GPPU register controls the pull-up resistors for the port pins.
+ *
+ * @param data The 8 bits to write to GPPUB register.
+ */
+ void gppub(char data);
+
+ /** Read INTFA.
+ *
+ * INTERRUPT FLAG REGISTER - READ ONLY
+ * The INTF register reflects the interrupt condition on the port pins of any pin that is enabled for interrupts via the GPINTEN register.
+ *
+ * @return The 8 bits read.
+ */
+ char intfa();
+
+ /** Read INTFB.
+ *
+ * INTERRUPT FLAG REGISTER - READ ONLY
+ * The INTF register reflects the interrupt condition on the port pins of any pin that is enabled for interrupts via the GPINTEN register.
+ *
+ * @return The 8 bits read.
+ */
+ char intfb();
+
+ /** Read INTCAPA.
+ *
+ * INTERRUPT CAPTURE REGISTER - READ ONLY
+ * The INTCAP register captures the GPIO port value at the time the interrupt occurred. The register is ‘read only’ and is updated only when an interrupt occurs.
+ *
+ * @return The 8 bits read.
+ */
+ char intcapa();
+
+ /** Read INTCAPB.
+ *
+ * INTERRUPT CAPTURE REGISTER - READ ONLY
+ * The INTCAP register captures the GPIO port value at the time the interrupt occurred. The register is ‘read only’ and is updated only when an interrupt occurs.
+ *
+ * @return The 8 bits read.
+ */
+ char intcapb();
+
+ /** Read GPIOA.
+ *
+ * PORT REGISTER
+ * The GPIO register reflects the value on the port. Reading from this register reads the port. Writing to this register modifies the Output Latch (OLAT) register.
+ *
+ * @return The 8 bits read.
+ */
+ char gpioa();
+
+ /** Write to GPIOA.
+ *
+ * PORT REGISTER
+ * The GPIO register reflects the value on the port. Reading from this register reads the port. Writing to this register modifies the Output Latch (OLAT) register.
+ *
+ * @param data The 8 bits to write to GPIOA register.
+ */
+ void gpioa(char data);
+
+ /** Read GPIOB.
+ *
+ * PORT REGISTER
+ * The GPIO register reflects the value on the port. Reading from this register reads the port. Writing to this register modifies the Output Latch (OLAT) register.
+ *
+ * @return The 8 bits read.
+ */
+ char gpiob();
+
+ /** Write to GPIOB.
+ *
+ * PORT REGISTER
+ * The GPIO register reflects the value on the port. Reading from this register reads the port. Writing to this register modifies the Output Latch (OLAT) register.
+ *
+ * @param data The 8 bits to write to GPIOB register.
+ */
+ void gpiob(char data);
+
+ /** Read OLATA.
+ *
+ * OUTPUT LATCH REGISTER
+ * The OLAT register provides access to the output latches. A read from this register results in a read of the OLAT and not the port itself. A write to this register
+ * modifies the output latches that modifies the pins configured as outputs.
+ *
+ * @return The 8 bits read.
+ */
+ char olata();
+
+ /** Write to OLATA.
+ *
+ * OUTPUT LATCH REGISTER
+ * The OLAT register provides access to the output latches. A read from this register results in a read of the OLAT and not the port itself. A write to this register
+ * modifies the output latches that modifies the pins configured as outputs.
+ *
+ * @param data The 8 bits to write to OLATA register.
+ */
+ void olata(char data);
+
+ /** Read OLATB.
+ *
+ * OUTPUT LATCH REGISTER
+ * The OLAT register provides access to the output latches. A read from this register results in a read of the OLAT and not the port itself. A write to this register
+ * modifies the output latches that modifies the pins configured as outputs.
+ *
+ * @return The 8 bits read.
+ */
+ char olatb();
+
+ /** Write to OLATB.
+ *
+ * OUTPUT LATCH REGISTER
+ * The OLAT register provides access to the output latches. A read from this register results in a read of the OLAT and not the port itself. A write to this register
+ * modifies the output latches that modifies the pins configured as outputs.
+ *
+ * @param data The 8 bits to write to OLATB register.
+ */
+ void olatb(char data);
+
+ /** Write to IOCON.MIRROR
+ *
+ * IOCON REGISTER - INTERRUPT MIRROR BIT
+ * 1 = The INT pins are internally connected
+ * 0 = The INT pins are not connected. INTA is associated with PortA and INTB is associated with PortB
+ *
+ * @param mirror write true ('1') or false ('0').
+ */
+ void intmirror(bool mirror);
+
+ /** Write to IOCON.INTPOL
+ *
+ * IOCON REGISTER - INTERRUPT POLARITY BIT
+ * This bit sets the polarity of the INT output pin.
+ * 1 = Active-high.
+ * 0 = Active-low.
+ *
+ * @param polarity write true ('1') or false ('0').
+ */
+ void intpol(bool polarity);
+
+private:
+ int _hardwareaddress;
+ SPI& _spi;
+ DigitalOut _nCs;
+ DigitalOut _nReset;
+ char _writeopcode;
+ char _readopcode;
+ void _initialization();
+ void _make_opcode(int _hardwareaddress);
+ char _read(char address);
+ void _write(char address, char data);
+
+};
+
+#endif