core/homeassistant/components/modbus/sensor.py

238 lines
7.2 KiB
Python

"""Support for Modbus Register sensors."""
import logging
import struct
from typing import Any, Union
import voluptuous as vol
from homeassistant.components.sensor import PLATFORM_SCHEMA
from homeassistant.const import (
CONF_NAME,
CONF_OFFSET,
CONF_SLAVE,
CONF_STRUCTURE,
CONF_UNIT_OF_MEASUREMENT,
)
from homeassistant.helpers import config_validation as cv
from homeassistant.helpers.restore_state import RestoreEntity
from . import CONF_HUB, DEFAULT_HUB, DOMAIN as MODBUS_DOMAIN
_LOGGER = logging.getLogger(__name__)
CONF_COUNT = "count"
CONF_DATA_TYPE = "data_type"
CONF_PRECISION = "precision"
CONF_REGISTER = "register"
CONF_REGISTER_TYPE = "register_type"
CONF_REGISTERS = "registers"
CONF_REVERSE_ORDER = "reverse_order"
CONF_SCALE = "scale"
DATA_TYPE_CUSTOM = "custom"
DATA_TYPE_FLOAT = "float"
DATA_TYPE_INT = "int"
DATA_TYPE_UINT = "uint"
REGISTER_TYPE_HOLDING = "holding"
REGISTER_TYPE_INPUT = "input"
def number(value: Any) -> Union[int, float]:
"""Coerce a value to number without losing precision."""
if isinstance(value, int):
return value
if isinstance(value, str):
try:
value = int(value)
return value
except (TypeError, ValueError):
pass
try:
value = float(value)
return value
except (TypeError, ValueError):
raise vol.Invalid(f"invalid number {value}")
PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend(
{
vol.Required(CONF_REGISTERS): [
{
vol.Required(CONF_NAME): cv.string,
vol.Required(CONF_REGISTER): cv.positive_int,
vol.Optional(CONF_COUNT, default=1): cv.positive_int,
vol.Optional(CONF_DATA_TYPE, default=DATA_TYPE_INT): vol.In(
[DATA_TYPE_INT, DATA_TYPE_UINT, DATA_TYPE_FLOAT, DATA_TYPE_CUSTOM]
),
vol.Optional(CONF_HUB, default=DEFAULT_HUB): cv.string,
vol.Optional(CONF_OFFSET, default=0): number,
vol.Optional(CONF_PRECISION, default=0): cv.positive_int,
vol.Optional(CONF_REGISTER_TYPE, default=REGISTER_TYPE_HOLDING): vol.In(
[REGISTER_TYPE_HOLDING, REGISTER_TYPE_INPUT]
),
vol.Optional(CONF_REVERSE_ORDER, default=False): cv.boolean,
vol.Optional(CONF_SCALE, default=1): number,
vol.Optional(CONF_SLAVE): cv.positive_int,
vol.Optional(CONF_STRUCTURE): cv.string,
vol.Optional(CONF_UNIT_OF_MEASUREMENT): cv.string,
}
]
}
)
def setup_platform(hass, config, add_entities, discovery_info=None):
"""Set up the Modbus sensors."""
sensors = []
data_types = {DATA_TYPE_INT: {1: "h", 2: "i", 4: "q"}}
data_types[DATA_TYPE_UINT] = {1: "H", 2: "I", 4: "Q"}
data_types[DATA_TYPE_FLOAT] = {1: "e", 2: "f", 4: "d"}
for register in config.get(CONF_REGISTERS):
structure = ">i"
if register.get(CONF_DATA_TYPE) != DATA_TYPE_CUSTOM:
try:
structure = ">{}".format(
data_types[register.get(CONF_DATA_TYPE)][register.get(CONF_COUNT)]
)
except KeyError:
_LOGGER.error(
"Unable to detect data type for %s sensor, " "try a custom type",
register.get(CONF_NAME),
)
continue
else:
structure = register.get(CONF_STRUCTURE)
try:
size = struct.calcsize(structure)
except struct.error as err:
_LOGGER.error(
"Error in sensor %s structure: %s", register.get(CONF_NAME), err
)
continue
if register.get(CONF_COUNT) * 2 != size:
_LOGGER.error(
"Structure size (%d bytes) mismatch registers count " "(%d words)",
size,
register.get(CONF_COUNT),
)
continue
hub_name = register.get(CONF_HUB)
hub = hass.data[MODBUS_DOMAIN][hub_name]
sensors.append(
ModbusRegisterSensor(
hub,
register.get(CONF_NAME),
register.get(CONF_SLAVE),
register.get(CONF_REGISTER),
register.get(CONF_REGISTER_TYPE),
register.get(CONF_UNIT_OF_MEASUREMENT),
register.get(CONF_COUNT),
register.get(CONF_REVERSE_ORDER),
register.get(CONF_SCALE),
register.get(CONF_OFFSET),
structure,
register.get(CONF_PRECISION),
)
)
if not sensors:
return False
add_entities(sensors)
class ModbusRegisterSensor(RestoreEntity):
"""Modbus register sensor."""
def __init__(
self,
hub,
name,
slave,
register,
register_type,
unit_of_measurement,
count,
reverse_order,
scale,
offset,
structure,
precision,
):
"""Initialize the modbus register sensor."""
self._hub = hub
self._name = name
self._slave = int(slave) if slave else None
self._register = int(register)
self._register_type = register_type
self._unit_of_measurement = unit_of_measurement
self._count = int(count)
self._reverse_order = reverse_order
self._scale = scale
self._offset = offset
self._precision = precision
self._structure = structure
self._value = None
async def async_added_to_hass(self):
"""Handle entity which will be added."""
state = await self.async_get_last_state()
if not state:
return
self._value = state.state
@property
def state(self):
"""Return the state of the sensor."""
return self._value
@property
def name(self):
"""Return the name of the sensor."""
return self._name
@property
def unit_of_measurement(self):
"""Return the unit of measurement."""
return self._unit_of_measurement
def update(self):
"""Update the state of the sensor."""
if self._register_type == REGISTER_TYPE_INPUT:
result = self._hub.read_input_registers(
self._slave, self._register, self._count
)
else:
result = self._hub.read_holding_registers(
self._slave, self._register, self._count
)
val = 0
try:
registers = result.registers
if self._reverse_order:
registers.reverse()
except AttributeError:
_LOGGER.error(
"No response from hub %s, slave %s, register %s",
self._hub.name,
self._slave,
self._register,
)
return
byte_string = b"".join([x.to_bytes(2, byteorder="big") for x in registers])
val = struct.unpack(self._structure, byte_string)[0]
val = self._scale * val + self._offset
if isinstance(val, int):
self._value = str(val)
if self._precision > 0:
self._value += "." + "0" * self._precision
else:
self._value = f"{val:.{self._precision}f}"