mcp9808test.cpp

Outputs temperature data from a MCP9808 on stdout.

/*
 * This file is part of the DUDS project. It is subject to the BSD-style
 * license terms in the LICENSE file found in the top-level directory of this
 * distribution and at http://www.somewhere.org/somepath/license.html.
 * No part of DUDS, including this file, may be copied, modified, propagated,
 * or distributed except according to the terms contained in the LICENSE file.
 *
 * Copyright (C) 2020  Jeff Jackowski
 */
#include <duds/hardware/devices/instruments/MCP9808.hpp>
#include <duds/hardware/interface/linux/DevSmbus.hpp>
#include <duds/hardware/interface/SmbusErrors.hpp>
#include <iostream>
#include <thread>
#include <iomanip>
#include <assert.h>
#include <boost/exception/diagnostic_information.hpp>
#include <boost/program_options.hpp>

constexpr int valw = 8;
bool quit = false;

void runtest(duds::hardware::devices::instruments::MCP9808 &meter, int delay)
try {
    int succ = 0, fail = 0;
    std::cout << std::fixed << std::setprecision(3) << "Resolution: " <<
    meter.resolutionDegrees() << 'C' << std::endl;
    do {
        std::this_thread::sleep_for(std::chrono::seconds(delay));
        bool skip = true;
        try {
            meter.sample();
            ++succ;
            skip = false;
        } catch (duds::hardware::interface::SmbusErrorMessageLength &) {
            throw;
        } catch (duds::hardware::interface::SmbusErrorBusy &) {
            throw;
        } catch (duds::hardware::interface::SmbusErrorUnsupported &) {
            throw;
        } catch (...) {
            std::cerr << "Failed sample attempt " << ++fail << ":\n" <<
            boost::current_exception_diagnostic_information() << std::endl;
        }
        if (!skip) {
            duds::data::Quantity temp = meter.temperature();
            assert(temp.unit == duds::data::units::Kelvin);
            std::cout << "Temp: " << std::setw(6) <<
            temp.value << "K  " << std::setw(5) <<
            temp.value - 273.15 << "C  " << std::setw(5) <<
            temp.value * 1.8 - 459.67 << 'F' << std::endl;
        }
    } while (!quit);
    std::cout << "Read " << succ << " samples successfully, and failed to read "
    << fail << " samples.\n" << std::setprecision(2) <<
    100.0f * (float)fail / (float)(succ + fail) << "% failed." << std::endl;
} catch (...) {
    std::cerr << "Program failed in runtest(): " <<
    boost::current_exception_diagnostic_information() << std::endl;
}

int main(int argc, char *argv[])
try {
    std::string i2cpath;
    int addr;
    int delay;
    { // option parsing
        boost::program_options::options_description optdesc(
            "Options for MCP9808 test"
        );
        optdesc.add_options()
            ( // help info
                "help,h",
                "Show this help message"
            )
            ( // the I2C device file to use
                "i2cdev,i",
                boost::program_options::value<std::string>(&i2cpath)->
                    default_value("/dev/i2c-1"),
                "Specify I2C device file"
            ) // the time between samples
            (
                "address,a",
                boost::program_options::value<int>(&addr)->
                    default_value(0x18),
                "Device address"
            )
            (
                "delay,d",
                boost::program_options::value<int>(&delay)->
                    default_value(1),
                "Time in seconds bewteen samples"
            )
        ;
        boost::program_options::variables_map vm;
        boost::program_options::store(
            boost::program_options::parse_command_line(argc, argv, optdesc),
            vm
        );
        boost::program_options::notify(vm);
        if (vm.count("help")) {
            std::cout << "Test program for temperature sensor MCP9808\n"
            << argv[0] << " [options]\n" << optdesc << std::endl;
            return 0;
        }
    }
    std::unique_ptr<duds::hardware::interface::Smbus> smbus =
        std::make_unique<duds::hardware::interface::linux::DevSmbus>(
            i2cpath,
            addr,
            duds::hardware::interface::Smbus::NoPec()
        );
    duds::hardware::devices::instruments::MCP9808 meter(smbus);
    meter.start();
    std::thread doit(runtest, std::ref(meter), delay);
    std::cin.get();
    quit = true;
    doit.join();
} catch (...) {
    std::cerr << "Program failed in main(): " <<
    boost::current_exception_diagnostic_information() << std::endl;
    return 1;
}