mirror of
https://github.com/DCC-EX/CommandStation-EX.git
synced 2024-11-22 15:46:14 +01:00
102 lines
3.4 KiB
C++
102 lines
3.4 KiB
C++
/*
|
|
* © 2022 Paul M Antoine
|
|
* © 2021, Neil McKechnie. All rights reserved.
|
|
*
|
|
* This file is part of DCC++EX API
|
|
*
|
|
* This is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* It is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with CommandStation. If not, see <https://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#ifndef IO_MCP23008_H
|
|
#define IO_MCP23008_H
|
|
|
|
#include "IO_GPIOBase.h"
|
|
|
|
class MCP23008 : public GPIOBase<uint8_t> {
|
|
public:
|
|
static void create(VPIN firstVpin, uint8_t nPins, I2CAddress i2cAddress, int interruptPin=-1) {
|
|
if (checkNoOverlap(firstVpin, nPins,i2cAddress)) new MCP23008(firstVpin, nPins, i2cAddress, interruptPin);
|
|
}
|
|
|
|
private:
|
|
// Constructor
|
|
MCP23008(VPIN firstVpin, uint8_t nPins, I2CAddress i2cAddress, int interruptPin=-1)
|
|
: GPIOBase<uint8_t>((FSH *)F("MCP23008"), firstVpin, nPins, i2cAddress, interruptPin) {
|
|
|
|
requestBlock.setRequestParams(_I2CAddress, inputBuffer, sizeof(inputBuffer),
|
|
outputBuffer, sizeof(outputBuffer));
|
|
outputBuffer[0] = REG_GPIO;
|
|
}
|
|
|
|
void _writeGpioPort() override {
|
|
I2CManager.write(_I2CAddress, 2, REG_GPIO, _portOutputState);
|
|
}
|
|
void _writePullups() override {
|
|
// Set pullups only for in-use pins. This prevents pullup being set for a pin that
|
|
// is intended for use as an output but hasn't been written to yet.
|
|
I2CManager.write(_I2CAddress, 2, REG_GPPU, _portPullup & _portInUse);
|
|
}
|
|
void _writePortModes() override {
|
|
// Write 0 to IODIR for in-use pins that are outputs, 1 for others.
|
|
uint8_t temp = ~(_portMode & _portInUse);
|
|
I2CManager.write(_I2CAddress, 2, REG_IODIR, temp);
|
|
// Enable interrupt-on-change for in-use pins that are inputs (_portMode=0)
|
|
temp = ~_portMode & _portInUse;
|
|
I2CManager.write(_I2CAddress, 2, REG_INTCON, 0x00);
|
|
I2CManager.write(_I2CAddress, 2, REG_GPINTEN, temp);
|
|
}
|
|
void _readGpioPort(bool immediate) override {
|
|
if (immediate) {
|
|
uint8_t buffer;
|
|
I2CManager.read(_I2CAddress, &buffer, 1, 1, REG_GPIO);
|
|
_portInputState = buffer | _portMode;
|
|
} else {
|
|
// Queue new request
|
|
requestBlock.wait(); // Wait for preceding operation to complete
|
|
// Issue new request to read GPIO register
|
|
I2CManager.queueRequest(&requestBlock);
|
|
}
|
|
}
|
|
// This function is invoked when an I/O operation on the requestBlock completes.
|
|
void _processCompletion(uint8_t status) override {
|
|
if (status == I2C_STATUS_OK)
|
|
_portInputState = inputBuffer[0] | _portMode;
|
|
else
|
|
_portInputState = 0xff;
|
|
}
|
|
void _setupDevice() override {
|
|
// IOCON is set ODR=1 (open drain shared interrupt pin), INTPOL=0 (active-Low)
|
|
I2CManager.write(_I2CAddress, 2, REG_IOCON, 0x04);
|
|
_writePortModes();
|
|
_writePullups();
|
|
_writeGpioPort();
|
|
}
|
|
|
|
uint8_t inputBuffer[1];
|
|
uint8_t outputBuffer[1];
|
|
|
|
enum {
|
|
// Register definitions for MCP23008
|
|
REG_IODIR=0x00,
|
|
REG_GPINTEN=0x02,
|
|
REG_INTCON=0x04,
|
|
REG_IOCON=0x05,
|
|
REG_GPPU=0x06,
|
|
REG_GPIO=0x09,
|
|
};
|
|
|
|
};
|
|
|
|
#endif
|