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thijstriemstrathijstriemstra
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add MCP23S17 expander
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‎MultiPlexer_MCP23S17/MultiPlexer_MCP23S17.cpp‎

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/*
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* Copyright (c) 2021 Collab
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* All rights reserved
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*/
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/*
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MultiPlexer_MCP23S17.cpp - Control MCP23S17 16-channel digital multiplexer over SPI.
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*/
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#include "MultiPlexer_MCP23S17.h"
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MultiPlexer_MCP23S17::MultiPlexer_MCP23S17(SPIClass *spi, int cs_pin, Method btn_callback, uint8_t addr) {
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address = addr;
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_btnCallback = btn_callback;
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_mcp = new MCP23S17(spi, cs_pin, addr);
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}
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void MultiPlexer_MCP23S17::begin() {
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_mcp->begin();
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}
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void MultiPlexer_MCP23S17::init() {
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// set MCP23S17 pin modes and interrupt configurations
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// to set one pin: chip.pinMode(0, INPUT_PULLUP);
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setPins();
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// clear the interrupt value variables
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_mcpAReading = 0;
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_mcpBReading = 0;
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_mcpReading = 0;
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}
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void MultiPlexer_MCP23S17::setupInterruptHandler(uint8_t irq_pin, void (*ISR)(void), int value) {
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pinMode(irq_pin, INPUT_PULLUP);
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attachInterrupt(digitalPinToInterrupt(irq_pin), ISR, value);
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}
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/**
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* Runs the MCP Interrupt processing from the Arduino ISR
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* and then takes action (prints) on the MCP pins that went LOW.
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*/
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void MultiPlexer_MCP23S17::loop() {
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if (_flagMCPA > 0) {
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//Log.info(F("loop flagMCPA" CR));
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// get the bit count and write the bits to byteBit[] array
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readByteBits(0);
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// do some processing of each interrupted pin
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processPins(0);
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_flagMCPA = 0;
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}
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if (_flagMCPB > 0) {
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//Log.info(F("loop flagMCPB" CR));
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readByteBits(1);
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// do some processing of each interrupted pin
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processPins(1);
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_flagMCPB = 0;
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}
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}
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/**
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* Set all port expander pins to desired mode INPUT_PULLUP.
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* Set all port expander input pins interrupts
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*/
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void MultiPlexer_MCP23S17::setPins() {
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for (uint8_t ind = 0; ind <= totalPorts - 1; ind++) {
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_mcp->pinMode(ind, INPUT_PULLUP);
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_mcp->enableInterrupt(ind, FALLING);
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}
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// set port expander interrupt configuratons
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_mcp->setMirror(false);
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_mcp->setInterruptOD(false);
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_mcp->setInterruptLevel(LOW);
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// clear all interrupts on this port expander
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_mcpReading = _mcp->getInterruptValue();
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}
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/**
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* Take action on new pin interrupt values
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*/
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void MultiPlexer_MCP23S17::interruptMCP(uint8_t port) {
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// read the Port Expander Interrupt pins
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readBankPortIntPins(port);
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// read the Port Expander Interrupt values
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readBankPortIntVal(port);
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// take action on new pin interrupt values
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if (port < 1) {
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// set flag that Port A interrupt occurred
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_flagMCPA = 1;
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} else {
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// set flag that Port B interrupt occurred
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_flagMCPB = 1;
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}
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}
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/**
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* Process the port byteBits array of interrupted MCP pins
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*/
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void MultiPlexer_MCP23S17::processPins(uint8_t port) {
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uint8_t pin;
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if (port < 1) {
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// Port A
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// _byteACount = number of pins to process
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for (uint8_t ind = 0; ind < _byteACount; ind++) {
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// recover the bit number from sequential array
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pin = _byteABits[ind];
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// notify listeners
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_btnCallback.callback3IntArg(address, port, pin);
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}
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} else {
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// Port B
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// _byteBCount = number of pins to process
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for (uint8_t ind = 0; ind < _byteBCount; ind++) {
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// recover the bit number from sequential array
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pin = _byteBBits[ind];
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// notify listeners
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_btnCallback.callback3IntArg(address, port, pin);
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}
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}
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}
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/**
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* Read all Port Expander port interrupt pins.
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* save set bit to byteBits arrays
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* byteBits array can be sequentially processed later
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*/
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void MultiPlexer_MCP23S17::readByteBits(uint8_t port) {
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if (port < 1) {
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// Port A
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_byteACount = 0;
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for (uint8_t ind = 0; ind < 8; ind++) {
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// ~ inverts bit values
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if (bitRead(~_mcpAReading, ind)) {
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// save the bit number to sequential array
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_byteABits[_byteACount] = ind;
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_byteACount = _byteACount + 1;
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//Log.info(F("Port A whichBit: %d" CR), ind);
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}
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}
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//Log.info(F("_byteACount: %d" CR), _byteACount);
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} else {
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// Port B
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_byteBCount = 0;
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for (uint8_t ind = 0; ind < 8; ind++) {
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// ~ inverts bit values
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if (bitRead(~_mcpBReading, ind)) {
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// save the bit number to sequential array
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_byteBBits[_byteBCount] = ind;
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_byteBCount = _byteBCount + 1;
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//Log.info(F("Port B whichBit: %d" CR), ind);
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}
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}
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//Log.info(F("_byteBCount: %d" CR, _byteBCount);
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}
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}
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/**
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* Read all Port Expander port interrupt values
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*/
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void MultiPlexer_MCP23S17::readBankPortIntVal(uint8_t port) {
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if (port < 1) {
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// Port A
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_mcpAReading = _mcp->getInterruptAValue();
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//Log.info(F("Port A Interrupt Values: ")); print8Bits(_mcpAReading);
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} else {
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// Port B
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_mcpBReading = _mcp->getInterruptBValue();
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//Log.info(F("Port B Interrupt Values: ")); print8Bits(_mcpBReading);
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}
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}
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/**
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* Read all Port Expander port interrupt pins
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*/
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void MultiPlexer_MCP23S17::readBankPortIntPins(uint8_t port) {
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if (port < 1) {
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// Port A
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_mcpAReading = _mcp->getInterruptAPins();
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} else {
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// Port B
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_mcpBReading = _mcp->getInterruptBPins();
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}
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}
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void MultiPlexer_MCP23S17::print8Bits(uint8_t myByte) {
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for (uint8_t mask = 0x80; mask; mask >>= 1) {
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if (mask & myByte)
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Log.info(F("1"));
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else
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Log.info(F("0"));
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}
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}

‎MultiPlexer_MCP23S17/MultiPlexer_MCP23S17.h‎

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/*
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* Copyright (c) 2021 Collab
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* All rights reserved
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*/
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/*
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MultiPlexer_MCP23S17.h - Control MCP23S17 16-channel digital multiplexer over SPI.
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*/
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#ifndef MultiPlexer_MCP23S17_h
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#define MultiPlexer_MCP23S17_h
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#include <Arduino.h>
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#include <SPI.h>
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#include <Method.h>
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#include <MCP23S17.h>
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#include <ArduinoLog.h>
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class MultiPlexer_MCP23S17
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{
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public:
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MultiPlexer_MCP23S17(
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SPIClass *spi,
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int cs_pin,
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Method btn_callback,
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uint8_t addr = 0
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);
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void begin();
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void init();
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void loop();
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void interruptMCP(uint8_t port);
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void setupInterruptHandler(uint8_t irq_pin, void (*ISR)(void), int value);
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uint8_t address;
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const int totalPorts = 16;
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private:
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MCP23S17* _mcp;
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uint8_t _address;
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Method _btnCallback;
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/* 16-bit interrupt reading */
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volatile uint16_t _mcpReading = 0;
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/* 8-bit Port-A interrupt reading */
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volatile uint8_t _mcpAReading = 0;
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/* 8-bit Port-B interrupt reading */
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volatile uint8_t _mcpBReading = 0;
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/* number of bits set in byte */
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uint8_t _byteACount = 0;
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/* number of bits set in byte */
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uint8_t _byteBCount = 0;
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/* set bit array */
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uint8_t _byteABits[8] = {0};
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/* set bit array */
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uint8_t _byteBBits[8] = {0};
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volatile uint8_t _flagMCPA = 0;
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volatile uint8_t _flagINTA = 0;
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volatile uint8_t _flagMCPB = 0;
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volatile uint8_t _flagINTB = 0;
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void setPins();
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void processPins(uint8_t port);
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void print8Bits(uint8_t myByte);
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void readByteBits(uint8_t port);
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void readBankPortIntVal(uint8_t port);
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void readBankPortIntPins(uint8_t port);
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};
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#endif

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