Checks polarity of VMN

dev/test_2_mux_2024.py

@@ -52,7 +52,7 @@ if within_ohmpi:
     k._hw.switch_mux([1, 4, 2, 3], state='on')
     k._hw.vab_square_wave(12,1)
     k._hw.switch_mux([1, 4, 2, 3], state='off')
-    print(f'Resistance: {k._hw.last_rho :.2f} ohm, dev. {k._hw.last_dev:.2f} %, rx bias: {k._hw.rx._bias:.2f} ohm')
+    print(f'Resistance: {k._hw.last_rho :.2f} ohm, dev. {k._hw.last_dev:.2f} %, rx bias: {k._hw.rx._bias:.2f} mV')
     k._hw._plot_readings()
     plot_exec_log('ohmpi/logs/exec.log')
 change_config('../configs/config_default.py', verbose=False)
\ No newline at end of file

ohmpi/hardware_components/ohmpi_card_3_15.py

@@ -254,6 +254,6 @@ class Rx(RxAbstract):
         """ Gets the voltage VMN in Volts
         """
         self.exec_logger.event(f'{self.board_name}\trx_voltage\tbegin\t{datetime.datetime.utcnow()}')
-        u = AnalogIn(self._ads_voltage, ads.P0, ads.P1).voltage * self._coef_p2 * 1000. - self._bias  # TODO:  check if it should be negated
+        u = -AnalogIn(self._ads_voltage, ads.P0, ads.P1).voltage * self._coef_p2 * 1000. - self._bias  # TODO:  check if it should be negated
         self.exec_logger.event(f'{self.board_name}\trx_voltage\tend\t{datetime.datetime.utcnow()}')
         return u

ohmpi/hardware_system.py

@@ -202,7 +202,7 @@ class OhmPiHardware:
     @property
     def last_rho(self):
         if len(self.readings) > 1:
-            return np.mean(self.readings[:, 2] * self.readings[:, 4] / self.readings[:, 3])
+            return np.mean(np.abs(self.readings[:, 4]) / self.readings[:, 3])
         else:
             return np.nan