diff --git a/ohmpi.py b/ohmpi.py
index ef69102311fc53437687d550b44813276dff2d68..038d13728c4176bba30a9b9b10a597d8c5af37c3 100644
--- a/ohmpi.py
+++ b/ohmpi.py
@@ -397,7 +397,7 @@ class OhmPi(object):
return gain
- def compute_tx_volt(self):
+ def compute_tx_volt(self, best_tx_injtime=1):
"""Compute best voltage to inject to be in our range of Vmn
(10 mV - 4500 mV) and current (2 - 45 mA)
"""
@@ -418,14 +418,14 @@ class OhmPi(object):
for volt in range(2, 10, 2):
print('trying with v:', volt)
self.DPS.write_register(0x0000,volt,2) # fixe la voltage pour la mesure à 5V
- time.sleep(1) # inject for 1 s at least on DPS5005
+ time.sleep(best_tx_injtime) # inject for 1 s at least on DPS5005
# autogain
self.ads_current = ads.ADS1115(self.i2c, gain=2/3, data_rate=128, address=0x49)
self.ads_voltage = ads.ADS1115(self.i2c, gain=2/3, data_rate=128, address=0x48)
- print(AnalogIn(self.ads_current, ads.P0).voltage)
- print(AnalogIn(self.ads_voltage, ads.P0).voltage)
- print(AnalogIn(self.ads_voltage, ads.P2).voltage)
+ print('current P0', AnalogIn(self.ads_current, ads.P0).voltage)
+ print('voltage P0', AnalogIn(self.ads_voltage, ads.P0).voltage)
+ print('voltage P2', AnalogIn(self.ads_voltage, ads.P2).voltage)
gain_current = self.gain_auto(AnalogIn(self.ads_current, ads.P0))
gain_voltage0 = self.gain_auto(AnalogIn(self.ads_voltage, ads.P0))
gain_voltage2 = self.gain_auto(AnalogIn(self.ads_voltage, ads.P2))
@@ -507,7 +507,7 @@ class OhmPi(object):
def run_measurement(self, quad=[1, 2, 3, 4], nb_stack=None, injection_duration=None,
- best_tx=True, tx_volt=0, autogain=True):
+ best_tx=True, tx_volt=0, autogain=True, best_tx_injtime=1):
"""Do a 4 electrode measurement and measure transfer resistance obtained.
Parameters
@@ -551,7 +551,7 @@ class OhmPi(object):
# get best voltage to inject
if self.idps and tx_volt == 0:
- tx_volt, polarity = self.compute_tx_volt()
+ tx_volt, polarity = self.compute_tx_volt(best_tx_injtime=best_tx_injtime)
print('tx volt V:', tx_volt)
else:
polarity = 1
@@ -713,6 +713,8 @@ class OhmPi(object):
# measure all quad of the RS sequence
for i in range(0, quads.shape[0]):
quad = quads[i, :] # quadrupole
+ self.switch_mux_on(quad) # put before raising the pins (otherwise conflict i2c)
+ d = self.run_measurement(quad=quad, nb_stack=1, injection_duration=0.5, tx_volt=5, autogain=True)
# NOTE (GB): I'd use the self.run_measurement() for all this middle part so we an make use of autogain and so ...
# call the switch_mux function to switch to the right electrodes
@@ -726,31 +728,33 @@ class OhmPi(object):
# save data and print in a text file
#self.append_and_save(export_path_rs, current_measurement)
- self.switch_mux_on(quad) # put before raising the pins (otherwise conflict i2c)
# current injection
- self.pin0 = self.mcp.get_pin(0)
- self.pin0.direction = Direction.OUTPUT
- self.pin1 = self.mcp.get_pin(1)
- self.pin1.direction = Direction.OUTPUT
- self.pin0.value = False
- self.pin1.value = False
-
- # call the switch_mux function to switch to the right electrodes
+ # self.pin0 = self.mcp.get_pin(0)
+ # self.pin0.direction = Direction.OUTPUT
+ # self.pin1 = self.mcp.get_pin(1)
+ # self.pin1.direction = Direction.OUTPUT
+ # self.pin0.value = False
+ # self.pin1.value = False
+
+ # # call the switch_mux function to switch to the right electrodes
- self.ads_current = ads.ADS1115(self.i2c, gain=2 / 3, data_rate=860, address=0x48)
- # ADS1115 for voltage measurement (MN)
- self.ads_voltage = ads.ADS1115(self.i2c, gain=2 / 3, data_rate=860, address=0x49)
- self.pin1.value = True # inject from pin1 to self.pin0
- self.pin0.value = False
- time.sleep(0.5)
+ # self.ads_current = ads.ADS1115(self.i2c, gain=2 / 3, data_rate=860, address=0x48)
+ # # ADS1115 for voltage measurement (MN)
+ # self.ads_voltage = ads.ADS1115(self.i2c, gain=2 / 3, data_rate=860, address=0x49)
+ # self.pin1.value = True # inject from pin1 to self.pin0
+ # self.pin0.value = False
+ # time.sleep(0.5)
- # measure current and voltage
- current = AnalogIn(self.ads_current, ads.P0).voltage / (50 * self.r_shunt)
- voltage = -AnalogIn(self.ads_voltage, ads.P0, ADS.P2).voltage * 2.5
- resistance = voltage / current
+ # # measure current and voltage
+ # current = AnalogIn(self.ads_current, ads.P0).voltage / (50 * self.r_shunt)
+ # voltage = -AnalogIn(self.ads_voltage, ads.P0, ADS.P2).voltage * 2.5
+ # resistance = voltage / current
+ current = d['R [ohm]']
+ voltage = d['Vmn [mV]']
+ current = d['I [mA]']
print(str(quad) + '> I: {:>10.3f} mA, V: {:>10.3f} mV, R: {:>10.3f} Ohm'.format(
- current*1000, voltage*1000, resistance))
+ current, voltage, resistance))
# compute resistance measured (= contact resistance)
resist = abs(resistance / 1000)
@@ -776,8 +780,8 @@ class OhmPi(object):
# close mux path and put pin back to GND
self.switch_mux_off(quad)
- self.pin0.value = False
- self.pin1.value = False
+ #self.pin0.value = False
+ #self.pin1.value = False
self.reset_mux()
self.status = 'idle'