import importlib
from OhmPi.config import OHMPI_CONFIG
import adafruit_ads1x15.ads1115 as ads # noqa
from adafruit_ads1x15.analog_in import AnalogIn # noqa
from adafruit_mcp230xx.mcp23008 import MCP23008 # noqa
from digitalio import Direction # noqa
import minimalmodbus # noqa
import time
import numpy as np
import os
from OhmPi.hardware import TxAbstract, RxAbstract
controller_module = importlib.import_module(f'{OHMPI_CONFIG["hardware"]["controller"]["model"]}')
TX_CONFIG = OHMPI_CONFIG['rx']
RX_CONFIG = OHMPI_CONFIG['tx']
# hardware limits
voltage_min = 10. # mV
voltage_max = 4500.
RX_CONFIG['voltage_min'] = voltage_min # mV
RX_CONFIG['voltage_max'] = voltage_max
TX_CONFIG['current_min'] = voltage_min / (TX_CONFIG['R_shunt'] * 50) # mA
TX_CONFIG['current_max'] = voltage_max / (TX_CONFIG['R_shunt'] * 50)
TX_CONFIG['default_voltage'] = 5. # V
TX_CONFIG['voltage_max'] = 50. # V
TX_CONFIG['dps_switch_on_warm_up'] = 4. # 4 seconds
def _gain_auto(channel):
"""Automatically sets the gain on a channel
Parameters
----------
channel : ads.ADS1x15
Instance of ADS where voltage is measured.
Returns
-------
gain : float
Gain to be applied on ADS1115.
"""
gain = 2 / 3
if (abs(channel.voltage) < 2.040) and (abs(channel.voltage) >= 1.0):
gain = 2
elif (abs(channel.voltage) < 1.0) and (abs(channel.voltage) >= 0.500):
gain = 4
elif (abs(channel.voltage) < 0.500) and (abs(channel.voltage) >= 0.250):
gain = 8
elif abs(channel.voltage) < 0.250:
gain = 16
return gain
class Tx(TxAbstract):
def __init__(self, **kwargs):
kwargs.update({'board_name': os.path.basename(__file__).rstrip('.py')})
super().__init__(**kwargs)
self._voltage = kwargs.pop('voltage', TX_CONFIG['default_voltage'])
self.controller = kwargs.pop('controller', controller_module.Controller())
# I2C connexion to MCP23008, for current injection
self.mcp_board = MCP23008(self.controller.bus, address=TX_CONFIG['mcp_board_address'])
# ADS1115 for current measurement (AB)
self._adc_gain = 2/3
self._ads_current_address = 0x48
self._ads_current = ads.ADS1115(self.controller.bus, gain=self.adc_gain, data_rate=860,
address=self._ads_current_address)
# Relays for pulse polarity
self.pin0 = self.mcp_board.get_pin(0)
self.pin0.direction = Direction.OUTPUT
self.pin1 = self.mcp_board.get_pin(1)
self.pin1.direction = Direction.OUTPUT
self.polarity = 0
# DPH 5005 Digital Power Supply
self.pin2 = self.mcp_board.get_pin(2) # dps +
self.pin2.direction = Direction.OUTPUT
self.pin3 = self.mcp_board.get_pin(3) # dps -
self.pin3.direction = Direction.OUTPUT
self.turn_on()
time.sleep(TX_CONFIG['dps_switch_on_warm_up'])
self.DPS = minimalmodbus.Instrument(port='/dev/ttyUSB0', slaveaddress=1) # port name, address (decimal)
self.DPS.serial.baudrate = 9600 # Baud rate 9600 as listed in doc
self.DPS.serial.bytesize = 8 #
self.DPS.serial.timeout = 1. # greater than 0.5 for it to work
self.DPS.debug = False #
self.DPS.serial.parity = 'N' # No parity
self.DPS.mode = minimalmodbus.MODE_RTU # RTU mode
self.DPS.write_register(0x0001, 1000, 0) # max current allowed (100 mA for relays) :
# (last number) 0 is for mA, 3 is for A
# I2C connexion to MCP23008, for current injection
self.pin4 = self.mcp_board.get_pin(4) # Ohmpi_run
self.pin4.direction = Direction.OUTPUT
self.pin4.value = True
self.exec_logger.info(f'TX battery: {self.tx_bat:.1f} V')
self.turn_off()
@property
def adc_gain(self):
return self._adc_gain
@adc_gain.setter
def adc_gain(self, value):
assert value in [2/3, 2, 4, 8, 16]
self._adc_gain = value
self._ads_current = ads.ADS1115(self.controller.bus, gain=self.adc_gain, data_rate=860,
address=self._ads_current_address)
self.exec_logger.debug(f'Setting TX ADC gain to {value}')
def adc_gain_auto(self):
gain = _gain_auto(AnalogIn(self._ads_current, ads.P0))
self.exec_logger.debug(f'Setting TX ADC gain automatically to {gain}')
self.adc_gain = gain
def current_pulse(self, **kwargs):
super().current_pulse(**kwargs)
self.exec_logger.warning(f'Current pulse is not implemented for the {TX_CONFIG["model"]} board')
@property
def current(self):
""" Gets the current IAB in Amps
"""
return AnalogIn(self._ads_current, ads.P0).voltage * 1000. / (50 * TX_CONFIG['R_shunt']) # noqa measure current
@ current.setter
def current(self, value):
assert TX_CONFIG['current_min'] <= value <= TX_CONFIG['current_max']
self.exec_logger.warning(f'Current pulse is not implemented for the {TX_CONFIG["model"]} board')
def inject(self, state='on'):
super().inject(state=state)
if state=='on':
self.DPS.write_register(0x09, 1) # DPS5005 on
else:
self.DPS.write_register(0x09, 0) # DPS5005 off
@property
def polarity(self):
return super().polarity
@polarity.setter
def polarity(self, value):
super().polarity(value)
if value==1:
self.pin0.value = True
self.pin1.value = False
elif value==-1:
self.pin0.value = False
self.pin1.value = True
else:
self.pin0.value = False
self.pin1.value = False
#time.sleep(0.001) # TODO: check max switching time of relays
@property
def voltage(self):
return self._voltage
@voltage.setter
def voltage(self, value):
if value > TX_CONFIG['voltage_max']:
self.exec_logger.warning(f'Sorry, cannot inject more than {TX_CONFIG["voltage_max"]} V, '
f'set it back to {TX_CONFIG["default_voltage"]} V (default value).')
value = TX_CONFIG['default_voltage']
if value < 0.:
self.exec_logger.warning(f'Voltage should be given as a positive number. '
f'Set polarity to -1 to reverse voltage...')
value = np.abs(value)
self.DPS.write_register(0x0000, value, 2)
def turn_off(self):
super().turn_off()
self.pin2.value = False
self.pin3.value = False
def turn_on(self):
super().turn_on()
self.pin2.value = True
self.pin3.value = True
@property
def tx_bat(self):
tx_bat = self.DPS.read_register(0x05, 2)
if tx_bat < 12.:
self.soh_logger.debug(f'Low TX Battery: {tx_bat:.1f} V')
return tx_bat
def voltage_pulse(self, voltage=TX_CONFIG['default_voltage'], length=None, polarity=None):
""" Generates a square voltage pulse
Parameters
----------
voltage: float, optional
Voltage to apply in volts, tx_v_def is applied if omitted.
length: float, optional
Length of the pulse in seconds
polarity: 1,0,-1
Polarity of the pulse
"""
if length is None:
length = self.inj_time
if polarity is None:
polarity = self.polarity
self.polarity = polarity
self.voltage(voltage)
self.exec_logger.debug(f'Voltage pulse of {polarity*voltage:.3f} V for {length:.3f} s')
self.inject(state='on')
time.sleep(length)
self.inject(state='off')
class Rx(RxAbstract):
def __init__(self, **kwargs):
kwargs.update({'board_name': os.path.basename(__file__).rstrip('.py')})
super().__init__(**kwargs)
self.controller = kwargs.pop('controller', controller_module.Controller())
# ADS1115 for voltage measurement (MN)
self._ads_voltage_address = 0x49
self._adc_gain = 2/3
self._ads_voltage = ads.ADS1115(self.controller.bus, gain=self._adc_gain, data_rate=860, address=self._ads_voltage_address)
@property
def adc_gain(self):
return self._adc_gain
@adc_gain.setter
def adc_gain(self, value):
assert value in [2/3, 2, 4, 8, 16]
self._adc_gain = value
self._ads_voltage = ads.ADS1115(self.controller.bus, gain=self.adc_gain, data_rate=860,
address=self._ads_voltage_address)
self.exec_logger.debug(f'Setting RX ADC gain to {value}')
def adc_gain_auto(self):
gain_0 = _gain_auto(AnalogIn(self._ads_voltage, ads.P0))
gain_2 = _gain_auto(AnalogIn(self._ads_voltage, ads.P2))
gain = np.min([gain_0, gain_2])[0]
self.exec_logger.debug(f'Setting TX ADC gain automatically to {gain}')
self.adc_gain = gain
@property
def voltage(self):
""" Gets the voltage VMN in Volts
"""
u0 = AnalogIn(self._ads_voltage, ads.P0).voltage * 1000.
u2 = AnalogIn(self._ads_voltage, ads.P2).voltage * 1000.
u = np.max([u0,u2]) * (np.heaviside(u0-u2, 1.) * 2 - 1.) # gets the max between u0 & u2 and set the sign
self.exec_logger.debug(f'Reading voltages {u0} V and {u2} V on RX. Returning {u} V')
return u