import importlib
from OhmPi.config import HARDWARE_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.hardware.raspberry_pi_3')
TX_CONFIG = HARDWARE_CONFIG['tx']
RX_CONFIG = HARDWARE_CONFIG['rx']
# hardware characteristics and limitations
# *** RX ***
# ADC for voltage
voltage_adc_voltage_min = 10. # mV
voltage_adc_voltage_max = 4500. # mV
RX_CONFIG['voltage_min'] = np.min([voltage_adc_voltage_min, RX_CONFIG.pop('voltage_min', np.inf)]) # mV
RX_CONFIG['voltage_max'] = np.min([voltage_adc_voltage_max, RX_CONFIG.pop('voltage_max', np.inf)]) # mV
# *** TX ***
# ADC for current
current_adc_voltage_min = 10. # mV
current_adc_voltage_max = 4500. # mV
tx_mcp_board_address = 0x20 #
dps_voltage_max = 12. # V
dps_default_voltage = 12. # V
dps_switch_on_warmup = 0. # seconds
TX_CONFIG['current_min'] = np.min([current_adc_voltage_min / (TX_CONFIG['r_shunt'] * 50), TX_CONFIG.pop('current_min', np.inf)]) # mA
TX_CONFIG['current_max'] = np.min([current_adc_voltage_max / (TX_CONFIG['r_shunt'] * 50), TX_CONFIG.pop('current_max', np.inf)]) # mA
TX_CONFIG['voltage_max'] = np.min([dps_voltage_max, TX_CONFIG.pop('voltage_max', np.inf)]) # V
TX_CONFIG['default_voltage'] = np.min([TX_CONFIG.pop('default_voltage', dps_default_voltage), TX_CONFIG['voltage_max']]) # V
TX_CONFIG['dps_switch_on_warm_up'] = TX_CONFIG.pop('dps_switch_on_warmup', dps_switch_on_warmup)
TX_CONFIG['mcp_board_address'] = TX_CONFIG.pop('mcp_board_address', tx_mcp_board_address)
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._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
self.adc_gain = 2 / 3
# DPH 5005 Digital Power Supply
self.turn_on()
time.sleep(TX_CONFIG['dps_switch_on_warm_up'])
self.DPS = None
# 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):
TxAbstract.current_pulse(self, **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'):
TxAbstract.inject(self, state=state)
# Add specifics here...
@property
def polarity(self):
return TxAbstract.polarity.gset(self)
@polarity.setter
def polarity(self, value):
TxAbstract.polarity.fset(self, 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):
self.exec_logger.warning(f'Voltage cannot be set on {self.board_name}...')
def turn_off(self):
pass
def turn_on(self):
pass
@property
def tx_bat(self):
self.soh_logger.warning(f'Cannot get battery voltage on {self.board_name}')
self.exec_logger.debug(f'{self.board_name} cannot read battery voltage. Returning default battery voltage.')
return TX_CONFIG['low_battery']
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