#34 - implemented channel input impedance and coupling

src/example_scripts/continuous_averaging_fifo_mode.py

@@ -13,6 +13,7 @@
     ExternalTriggerMode,
     TriggerSettings,
     AcquisitionSettings,
+    InputImpedance,
 )
 
 
@@ -56,6 +57,7 @@ def continuous_averaging_multi_fifo_example(
         enabled_channels=[0],
         vertical_ranges_in_mv=[200],
         vertical_offsets_in_percent=[0],
+        input_impedances=[InputImpedance.ONE_MEGA_OHM],
         timestamping_enabled=True,
         number_of_averages=num_averages,
     )

src/example_scripts/continuous_multi_fifo_mode.py

@@ -13,6 +13,7 @@
     ExternalTriggerMode,
     TriggerSettings,
     AcquisitionSettings,
+    InputImpedance,
 )
 
 
@@ -56,6 +57,7 @@ def continuous_multi_fifo_example(
         enabled_channels=[0],
         vertical_ranges_in_mv=[200],
         vertical_offsets_in_percent=[0],
+        input_impedances=[InputImpedance.ONE_MEGA_OHM],
         timestamping_enabled=True,
         batch_size=batch_size,
     )

src/example_scripts/finite_multi_fifo_mode.py

@@ -11,6 +11,7 @@
     ExternalTriggerMode,
     TriggerSettings,
     AcquisitionSettings,
+    InputImpedance,
 )
 
 
@@ -54,6 +55,7 @@ def finite_multi_fifo_example(
         enabled_channels=[0],
         vertical_ranges_in_mv=[200],
         vertical_offsets_in_percent=[0],
+        input_impedances=[InputImpedance.ONE_MEGA_OHM],
         timestamping_enabled=True,
         batch_size=batch_size,
     )

src/example_scripts/standard_single_mode.py

@@ -13,6 +13,7 @@
     ExternalTriggerMode,
     TriggerSettings,
     AcquisitionSettings,
+    InputImpedance,
 )
 
 
@@ -54,6 +55,7 @@ def standard_single_mode_example(
         enabled_channels=[0],
         vertical_ranges_in_mv=[200],
         vertical_offsets_in_percent=[0],
+        input_impedances=[InputImpedance.ONE_MEGA_OHM],
         timestamping_enabled=True,
     )
 

src/example_scripts/star_hub_example.py

@@ -8,6 +8,7 @@
     ExternalTriggerMode,
     AcquisitionMode,
     AcquisitionSettings,
+    InputImpedance,
 )
 
 
@@ -67,8 +68,9 @@ def connect_to_star_hub_example(
         pre_trigger_length_in_samples=0,
         timeout_in_ms=1000,
         enabled_channels=[0, 8],  # at least 1 channel from each child card must be enabled
-        vertical_ranges_in_mv=[200],
-        vertical_offsets_in_percent=[0],
+        vertical_ranges_in_mv=[200, 200],
+        vertical_offsets_in_percent=[0, 0],
+        input_impedances=[InputImpedance.ONE_MEGA_OHM, InputImpedance.ONE_MEGA_OHM],
         timestamping_enabled=True,
         batch_size=5,
     )

src/spectrumdevice/devices/digitiser/abstract_spectrum_digitiser.py

@@ -40,11 +40,22 @@ def configure_acquisition(self, settings: AcquisitionSettings) -> None:
         )
         self.set_timeout_in_ms(settings.timeout_in_ms)
         self.set_enabled_channels(settings.enabled_channels)
-        for channel, v_range, v_offset in zip(
-            self.channels, settings.vertical_ranges_in_mv, settings.vertical_offsets_in_percent
+
+        # Apply channel dependent settings
+        for channel, v_range, v_offset, impedance in zip(
+            self.channels,
+            settings.vertical_ranges_in_mv,
+            settings.vertical_offsets_in_percent,
+            settings.input_impedances,
         ):
             cast(SpectrumDigitiserChannel, channel).set_vertical_range_in_mv(v_range)
             cast(SpectrumDigitiserChannel, channel).set_vertical_offset_in_percent(v_offset)
+            cast(SpectrumDigitiserChannel, channel).set_input_impedance(impedance)
+
+        # Only some hardware has software programmable input coupling, so coupling can be None
+        if settings.input_couplings is not None:
+            for channel, coupling in zip(self.channels, settings.input_couplings):
+                cast(SpectrumDigitiserChannel, channel).set_input_coupling(coupling)
 
         # Write the configuration to the card
         self.write_to_spectrum_device_register(SPC_M2CMD, M2CMD_CARD_WRITESETUP)

src/spectrumdevice/devices/digitiser/digitiser_channel.py

@@ -13,8 +13,14 @@
 )
 from spectrumdevice.exceptions import SpectrumCardIsNotADigitiser
 from spectrumdevice.settings.card_dependent_properties import CardType
-from spectrumdevice.settings.channel import INPUT_IMPEDANCE_COMMANDS, InputImpedance, VERTICAL_OFFSET_COMMANDS, \
-    VERTICAL_RANGE_COMMANDS
+from spectrumdevice.settings.channel import (
+    INPUT_IMPEDANCE_COMMANDS,
+    InputImpedance,
+    VERTICAL_OFFSET_COMMANDS,
+    VERTICAL_RANGE_COMMANDS,
+    InputCoupling,
+    INPUT_COUPLING_COMMANDS,
+)
 
 
 class SpectrumDigitiserChannel(AbstractSpectrumChannel, SpectrumDigitiserChannelInterface):
@@ -90,5 +96,17 @@ def input_impedance(self) -> InputImpedance:
         return InputImpedance(impedance_binary_value)
 
     def set_input_impedance(self, input_impedance: InputImpedance) -> None:
-        self._parent_device.write_to_spectrum_device_register(INPUT_IMPEDANCE_COMMANDS[self._number],
-                                                              input_impedance.value)
+        self._parent_device.write_to_spectrum_device_register(
+            INPUT_IMPEDANCE_COMMANDS[self._number], input_impedance.value
+        )
+
+    @property
+    def input_coupling(self) -> InputCoupling:
+        """The current input impedance setting of the channel (50 Ohm or 1 MOhm)"""
+        coupling_binary_value = self._parent_device.read_spectrum_device_register(INPUT_COUPLING_COMMANDS[self._number])
+        return InputCoupling(coupling_binary_value)
+
+    def set_input_coupling(self, input_coupling: InputCoupling) -> None:
+        self._parent_device.write_to_spectrum_device_register(
+            INPUT_COUPLING_COMMANDS[self._number], input_coupling.value
+        )

src/spectrumdevice/devices/digitiser/digitiser_interface.py

@@ -14,7 +14,7 @@
 from spectrumdevice.devices.abstract_device import SpectrumChannelInterface, SpectrumDeviceInterface
 from spectrumdevice.settings import AcquisitionMode, AcquisitionSettings
 from spectrumdevice import Measurement
-from spectrumdevice.settings.channel import InputImpedance
+from spectrumdevice.settings.channel import InputImpedance, InputCoupling
 
 
 class SpectrumDigitiserChannelInterface(SpectrumChannelInterface, ABC):
@@ -52,6 +52,15 @@ def input_impedance(self) -> InputImpedance:
     def set_input_impedance(self, input_impedance: InputImpedance) -> None:
         raise NotImplementedError()
 
+    @property
+    @abstractmethod
+    def input_coupling(self) -> InputCoupling:
+        raise NotImplementedError()
+
+    @abstractmethod
+    def set_input_coupling(self, input_coupling: InputCoupling) -> None:
+        raise NotImplementedError()
+
 
 class SpectrumDigitiserInterface(SpectrumDeviceInterface, ABC):
     """Defines the public interface for control of all Spectrum digitiser devices, be they StarHub composite devices

src/spectrumdevice/settings/__init__.py

@@ -11,7 +11,7 @@
 
 from spectrumdevice.settings.card_dependent_properties import ModelNumber
 from spectrumdevice.settings.card_features import CardFeature, AdvancedCardFeature
-from spectrumdevice.settings.channel import InputImpedance
+from spectrumdevice.settings.channel import InputImpedance, InputCoupling
 from spectrumdevice.settings.device_modes import AcquisitionMode, ClockMode
 from spectrumdevice.settings.io_lines import IOLineMode, AvailableIOModes
 from spectrumdevice.settings.transfer_buffer import (
@@ -87,6 +87,8 @@ class AcquisitionSettings:
       SpectrumDigitiserCard.get_waveforms()."""
     number_of_averages: int = 1
     """If an averaging AcquisitionMode is selected, this defines the number of averages."""
+    input_couplings: Optional[List[InputCoupling]] = None
+    """The coupling (AC or DC) to apply to each channel. Only available on some hardware, so default is None."""
 
 
 class SpectrumRegisterLength(Enum):

src/spectrumdevice/settings/channel.py

@@ -13,7 +13,15 @@
     SPCM_STOPLVL_HOLDLAST,
     SPCM_STOPLVL_LOW,
     SPCM_STOPLVL_ZERO,
-    SPC_50OHM0, SPC_50OHM1, SPC_50OHM10, SPC_50OHM11, SPC_50OHM12, SPC_50OHM13, SPC_50OHM14, SPC_50OHM15, SPC_50OHM2,
+    SPC_50OHM0,
+    SPC_50OHM1,
+    SPC_50OHM10,
+    SPC_50OHM11,
+    SPC_50OHM12,
+    SPC_50OHM13,
+    SPC_50OHM14,
+    SPC_50OHM15,
+    SPC_50OHM2,
     SPC_50OHM3,
     SPC_50OHM4,
     SPC_50OHM5,
@@ -101,6 +109,22 @@
     CHANNEL13,
     CHANNEL14,
     CHANNEL15,
+    SPC_ACDC0,
+    SPC_ACDC1,
+    SPC_ACDC2,
+    SPC_ACDC3,
+    SPC_ACDC4,
+    SPC_ACDC5,
+    SPC_ACDC6,
+    SPC_ACDC7,
+    SPC_ACDC8,
+    SPC_ACDC9,
+    SPC_ACDC10,
+    SPC_ACDC11,
+    SPC_ACDC12,
+    SPC_ACDC13,
+    SPC_ACDC14,
+    SPC_ACDC15,
 )
 
 VERTICAL_RANGE_COMMANDS = (
@@ -251,4 +275,29 @@ class InputImpedance(Enum):
     SPC_50OHM13,
     SPC_50OHM14,
     SPC_50OHM15,
-)
+)
+
+
+class InputCoupling(Enum):
+    AC = 1
+    DC = 0
+
+
+INPUT_COUPLING_COMMANDS = (
+    SPC_ACDC0,
+    SPC_ACDC1,
+    SPC_ACDC2,
+    SPC_ACDC3,
+    SPC_ACDC4,
+    SPC_ACDC5,
+    SPC_ACDC6,
+    SPC_ACDC7,
+    SPC_ACDC8,
+    SPC_ACDC9,
+    SPC_ACDC10,
+    SPC_ACDC11,
+    SPC_ACDC12,
+    SPC_ACDC13,
+    SPC_ACDC14,
+    SPC_ACDC15,
+)

src/tests/configuration.py

@@ -12,8 +12,8 @@ class SpectrumTestMode(Enum):
 
 # Set to TestMode.MOCK_HARDWARE for software-only testing, even if Spectrum drivers are found on the system
 # Set to TestMode.REAL_HARDWARE to run tests on a real hardware device as configured below.
-SINGLE_CARD_TEST_MODE = SpectrumTestMode.MOCK_HARDWARE
-STAR_HUB_TEST_MODE = SpectrumTestMode.MOCK_HARDWARE
+SINGLE_CARD_TEST_MODE = SpectrumTestMode.REAL_HARDWARE
+STAR_HUB_TEST_MODE = SpectrumTestMode.REAL_HARDWARE
 
 # Set IP address of real spectrum device (for use if TestMode.REAL_HARDWARE is set above). Set to None to run tests on
 # a local (PCIe) card.
@@ -36,7 +36,7 @@ class SpectrumTestMode(Enum):
 MOCK_DEVICE_TEST_FRAME_RATE_HZ = 10.0
 
 # Trigger source to use for integration tests. Has no effect in SpectrumTestMode.MOCK_HARDWARE
-INTEGRATION_TEST_TRIGGER_SOURCE = TriggerSource.SPC_TMASK_EXT0
+INTEGRATION_TEST_TRIGGER_SOURCE = TriggerSource.SPC_TMASK_SOFTWARE
 
 
 if SINGLE_CARD_TEST_MODE == SpectrumTestMode.REAL_HARDWARE and not SPECTRUM_DRIVERS_FOUND:

src/tests/test_single_channel.py

@@ -1,6 +1,7 @@
 from unittest import TestCase
 
 from spectrumdevice import SpectrumDigitiserChannel
+from spectrumdevice.settings import InputImpedance
 from tests.device_factories import create_spectrum_card_for_testing
 
 
@@ -21,3 +22,8 @@ def test_vertical_offset(self) -> None:
         offset = 1
         self._channel.set_vertical_offset_in_percent(offset)
         self.assertEqual(offset, self._channel.vertical_offset_in_percent)
+
+    def test_input_impedance(self) -> None:
+        impedance = InputImpedance.ONE_MEGA_OHM
+        self._channel.set_input_impedance(impedance)
+        self.assertEqual(impedance, self._channel.input_impedance)