s2k_device.cpp

#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/select.h>
#include <fcntl.h>
#include <stdio.h>
#include <termios.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <iostream>

#include "s2k_device.h"

namespace
{
    const int PAUSE_US = 100000;
}

REGISTER_BASIC_INT_PROTOCOL("s2k", TS2KDevice, TRegisterTypes(
        {
            { TS2KDevice::REG_RELAY, "relay", "switch", U8 },
            { TS2KDevice::REG_RELAY_MODE, "relay_mode", "value", U8, true },
            { TS2KDevice::REG_RELAY_DEFAULT, "relay_default", "value", U8, true },
            { TS2KDevice::REG_RELAY_DELAY, "relay_delay", "value", U8, true }
        }));

TS2KDevice::TS2KDevice(PDeviceConfig config, PPort port, PProtocol protocol)
    : TBasicProtocolSerialDevice<TBasicProtocol<TS2KDevice>>(config, port, protocol)
{
    RelayState[1] = 2;
    RelayState[2] = 2;
    RelayState[3] = 2;
    RelayState[4] = 2;
}

uint8_t TS2KDevice::CrcTable[] = {
        0x00,0x5E,0xBC,0xE2,0x61,0x3F,0xDD,0x83,0xC2,0x9C,0x7E,0x20,0xA3,0xFD,
        0x1F,0x41,0x9D,0xC3,0x21,0x7F,0xFC,0xA2,0x40,0x1E,0x5F,0x01,0xE3,0xBD,
        0x3E,0x60,0x82,0xDC,0x23,0x7D,0x9F,0xC1,0x42,0x1C,0xFE,0xA0,0xE1,0xBF,
        0x5D,0x03,0x80,0xDE,0x3C,0x62,0xBE,0xE0,0x02,0x5C,0xDF,0x81,0x63,0x3D,
        0x7C,0x22,0xC0,0x9E,0x1D,0x43,0xA1,0xFF,0x46,0x18,0xFA,0xA4,0x27,0x79,
        0x9B,0xC5,0x84,0xDA,0x38,0x66,0xE5,0xBB,0x59,0x07,0xDB,0x85,0x67,0x39,
        0xBA,0xE4,0x06,0x58,0x19,0x47,0xA5,0xFB,0x78,0x26,0xC4,0x9A,0x65,0x3B,
        0xD9,0x87,0x04,0x5A,0xB8,0xE6,0xA7,0xF9,0x1B,0x45,0xC6,0x98,0x7A,0x24,
        0xF8,0xA6,0x44,0x1A,0x99,0xC7,0x25,0x7B,0x3A,0x64,0x86,0xD8,0x5B,0x05,
        0xE7,0xB9,0x8C,0xD2,0x30,0x6E,0xED,0xB3,0x51,0x0F,0x4E,0x10,0xF2,0xAC,
        0x2F,0x71,0x93,0xCD,0x11,0x4F,0xAD,0xF3,0x70,0x2E,0xCC,0x92,0xD3,0x8D,
        0x6F,0x31,0xB2,0xEC,0x0E,0x50,0xAF,0xF1,0x13,0x4D,0xCE,0x90,0x72,0x2C,
        0x6D,0x33,0xD1,0x8F,0x0C,0x52,0xB0,0xEE,0x32,0x6C,0x8E,0xD0,0x53,0x0D,
        0xEF,0xB1,0xF0,0xAE,0x4C,0x12,0x91,0xCF,0x2D,0x73,0xCA,0x94,0x76,0x28,
        0xAB,0xF5,0x17,0x49,0x08,0x56,0xB4,0xEA,0x69,0x37,0xD5,0x8B,0x57,0x09,
        0xEB,0xB5,0x36,0x68,0x8A,0xD4,0x95,0xCB,0x29,0x77,0xF4,0xAA,0x48,0x16,
        0xE9,0xB7,0x55,0x0B,0x88,0xD6,0x34,0x6A,0x2B,0x75,0x97,0xC9,0x4A,0x14,
        0xF6,0xA8,0x74,0x2A,0xC8,0x96,0x15,0x4B,0xA9,0xF6,0xB6,0xFC,0x0A,0x54,
        0xD7,0x89,0x6B,0x35
};

uint8_t TS2KDevice::CrcS2K(const uint8_t *array, int size)
{
    uint8_t crc = 0;
    for (int i = 0; i < size; i++) {
        crc = CrcTable[crc ^ array[i]];
    }
    return crc;
}

// TODO: refactor this when more registers are writable, move writing
// and error handling into separate function
void TS2KDevice::WriteRegister(PRegister reg, uint64_t value)
{
    if (reg->Type != REG_RELAY) {
        throw TSerialDeviceException("S2K protocol: invalid register for writing");
    }

    if (reg->Address < 1 || reg->Address > 4) {
        throw TSerialDeviceException("S2K protocol: invalid register address");
    }

    Port()->CheckPortOpen();
    uint8_t command[7] = {
            /* Address = */(uint8_t)SlaveId,
            /* Command length = */0x06,
            /* Key = */0x00,
            /* Command = */0x15,/* Relay control */
            /* Relay No = */(uint8_t)reg->Address,
            /* Relay program = */(uint8_t)(value ? 0x1/* ON */ : 0x2/* OFF */),
            /* CRC placeholder */0x0
        };
    command[6] = CrcS2K(command, 6);
    Port()->WriteBytes(command, 7);
    uint8_t response[256];
    int size = Port()->ReadFrame(response, 256, std::chrono::microseconds(PAUSE_US));
    if (size != 6 ||
       response[0] != (uint8_t)SlaveId ||
       response[1] != 5 ||
       response[2]!= 0x16)
    {
        throw TSerialDeviceTransientErrorException("incorrect response for 0x15 command");
    }
    if (response[5] != CrcS2K(response, 5)) {
        throw TSerialDeviceTransientErrorException("bad CRC for 0x15 command");
    }
    RelayState[response[3]] = response[4];
}

// TODO: refactor this when more registers are actually readable, move reading
// and error handling into separate function
uint64_t TS2KDevice::ReadRegister(PRegister reg)
{
    /* We have no way to get current relay state from device. Thats why we save last
       successful write to relay register and return it when regiter is read */
    switch (reg->Type) {
    case REG_RELAY:
        return RelayState[reg->Address] != 0 && RelayState[reg->Address] != 2;
    case REG_RELAY_MODE:
        return RelayState[reg->Address];
    case REG_RELAY_DEFAULT:
    case REG_RELAY_DELAY:
    {
        Port()->CheckPortOpen();
        /* Default state of relays is stored in configs 1-4,
           Default delay for relays - in configs 5-8 */
        uint8_t command[7] = {
                /* Address = */(uint8_t)SlaveId,
                /* Command length = */0x06,
                /* Key = */0x00,
                /* Command = */0x05,/* Read configutation */
                /* Config No = */(uint8_t)(reg->Address +
                                     (reg->Type == REG_RELAY_DELAY ? 4 : 0)),
                /* Unused */0x0,
                /* CRC placeholder */0x0
            };
        command[6] = CrcS2K(command, 6);
        Port()->WriteBytes(command, 7);
        uint8_t response[256];
        int size = Port()->ReadFrame(response, 256, std::chrono::microseconds(PAUSE_US));
        if (size != 6 ||
           response[0] != (uint8_t)SlaveId ||
           response[1] != 0x5 ||
           response[2] != 0x6)
        {
            throw TSerialDeviceTransientErrorException("incorrect response for 0x5 command");
        }
        if (response[5] != CrcS2K(response, 5)){
            throw TSerialDeviceTransientErrorException("bad CRC for 0x5 command");
        }
        return response[4];
    }
    default:
        throw TSerialDeviceException("S2K protocol: invalid register for reading");
    }
}