[WIP] improved client control

yaqd_scpi/_scpi_base.py

@@ -0,0 +1,36 @@
+__all__ = ["SCPIBase"]
+
+import pyvisa
+import sys
+import asyncio
+
+from yaqd_core import IsDaemon
+
+
+class SCPIBase(IsDaemon):
+    _kind = "scpi-sensor"
+
+    def __init__(self, name, config, config_filepath):
+        super().__init__(name, config, config_filepath)
+        if sys.platform.startswith("win32"):
+            rm = pyvisa.ResourceManager()  # use ni-visa backend
+        else:
+            rm = pyvisa.ResourceManager("@py")  # use pyvisa-py backend
+        self._instrument: pyvisa.Resource = rm.open_resource(config["visa_address"], timeout=500)
+
+    def direct_scpi_write(self, command: str):
+        self._instrument.write(command)
+
+    def direct_scpi_query(self, command: str) -> str:
+        assert "?" in command
+        return str(self._instrument.query(command))
+
+    def extra_scpi_read(self):
+        """
+        purely for debugging
+        """
+        read = self._instrument.read()
+        self.logger.info(f"extra read: {read}")
+
+    def close(self):
+        self._instrument.close()

yaqd_scpi/_scpi_sensor.py

@@ -5,27 +5,35 @@
 from typing import Dict, Any, List
 
 import pyvisa
+import numpy as np
 
-from yaqd_core import HasMeasureTrigger, IsSensor, IsDaemon
+from yaqd_core import HasMeasureTrigger, IsSensor
+from ._scpi_base import SCPIBase
 
 
-class SCPISensor(HasMeasureTrigger, IsSensor, IsDaemon):
+class SCPISensor(HasMeasureTrigger, IsSensor, SCPIBase):
     _kind = "scpi-sensor"
 
     def __init__(self, name, config, config_filepath):
         super().__init__(name, config, config_filepath)
         self._channel_names = list(config["channels"].keys())
         self._channel_units = {k: config["channels"][k]["units"] for k in self._channel_names}
-        if sys.platform.startswith("win32"):
-            rm = pyvisa.ResourceManager()  # use ni-visa backend
-        else:
-            rm = pyvisa.ResourceManager("@py")  # use pyvisa-py backend
-        self._instrument = rm.open_resource(config["visa_address"])
 
     async def _measure(self):
+        query_error = False
         out = {}
         for k in self._channel_names:
-            query = self._config["channels"][k]["query"]
-            self._instrument.write(query)
-            out[k] = float(self._instrument.read())
+            while True:
+                try:
+                    response = self._instrument.query(self._config["channels"][k]["query"])
+                except Exception as e:
+                    self.logger.error(f"error in _measure with key {k}")
+                    self.logger.error(e)
+                    query_error = True
+                    await asyncio.sleep(0.1)
+                    continue
+                out[k] = float(response)
+                break
+        if query_error:
+            self.logger.info(f"afer error, {k} = {str(out)}")
         return out

yaqd_scpi/_scpi_set_continuous.py

@@ -6,20 +6,16 @@
 
 import pyvisa
 
-from yaqd_core import HasLimits, HasPosition, IsDaemon
+from yaqd_core import HasLimits, HasPosition
+from ._scpi_base import SCPIBase
 
 
-class SCPISetContinuous(HasLimits, HasPosition, IsDaemon):
+class SCPISetContinuous(HasLimits, HasPosition, SCPIBase):
     _kind = "scpi-set-continuous"
 
     def __init__(self, name, config, config_filepath):
         super().__init__(name, config, config_filepath)
         self._scpi_command = self._config["scpi_command"]
-        if sys.platform.startswith("win32"):
-            rm = pyvisa.ResourceManager()  # use ni-visa backend
-        else:
-            rm = pyvisa.ResourceManager("@py")  # use pyvisa-py backend
-        self._instrument = rm.open_resource(config["visa_address"])
 
     def _set_position(self, position):
         self._busy = True

yaqd_scpi/_scpi_set_discrete.py

@@ -6,21 +6,17 @@
 
 import pyvisa
 
-from yaqd_core import IsDiscrete, HasPosition, IsDaemon
+from yaqd_core import IsDiscrete, HasPosition
+from ._scpi_base import SCPIBase
 
 
-class SCPISetDiscrete(IsDiscrete, HasPosition, IsDaemon):
+class SCPISetDiscrete(IsDiscrete, HasPosition, SCPIBase):
     _kind = "scpi-set-discrete"
 
     def __init__(self, name, config, config_filepath):
         super().__init__(name, config, config_filepath)
         self._scpi_command = self._config["scpi_command"]
         self._identifiers_by_position = {k: v for v, k in self._config["identifiers"].items()}
-        if sys.platform.startswith("win32"):
-            rm = pyvisa.ResourceManager()  # use ni-visa backend
-        else:
-            rm = pyvisa.ResourceManager("@py")  # use pyvisa-py backend
-        self._instrument = rm.open_resource(config["visa_address"])
 
     def _set_position(self, position):
         self._busy = True

yaqd_scpi/scpi-sensor.avpr

@@ -96,6 +96,31 @@
             "request": [],
             "response": "boolean"
         },
+        "direct_scpi_query": {
+            "doc": "",
+            "request": [
+                {
+                    "name": "command",
+                    "type": "string"
+                }
+            ],
+            "response": "string"
+        },
+        "direct_scpi_write": {
+            "doc": "write a SCPI command",
+            "request": [
+                {
+                    "name": "command",
+                    "type": "string"
+                }
+            ],
+            "response": "null"
+        },
+        "extra_scpi_read": {
+            "doc": "",
+            "request": [],
+            "response": "null"
+        },
         "get_channel_names": {
             "doc": "Get current channel names.",
             "origin": "is-sensor",
@@ -230,8 +255,8 @@
                     "default": null,
                     "name": "units",
                     "type": [
-                        "string",
-                        "null"
+                        "null",
+                        "string"
                     ]
                 }
             ],

yaqd_scpi/scpi-sensor.toml

@@ -15,7 +15,7 @@ conda-forge = "https://anaconda.org/conda-forge/yaqd-scpi"
 type = "record"
 name = "channel"
 fields = [{"name"="query", "type"="string", "doc"="SCPI query, e.g. MEAS:VOLT:DC?"},
-	  {"name"="units", "type"=["string", "null"], "default"="__null__"}]
+	  {"name"="units", "type"=["null", "string"], "default"="__null__"}]
 
 [config]
 
@@ -26,4 +26,16 @@ default = {}
 
 [config.visa_address]
 type = "string"
-doc = "VISA resource name."
+doc = "VISA resource name."
+
+[messages.direct_scpi_write]
+doc = "write a SCPI command"
+request = [{"name"="command", "type"="string"}]
+
+[messages.direct_scpi_query]
+doc = ""
+request = [{"name"="command", "type"="string"}]
+response = "string"
+
+[messages.extra_scpi_read]
+doc = ""

yaqd_scpi/scpi-set-continuous.avpr

@@ -119,6 +119,16 @@
             "request": [],
             "response": "boolean"
         },
+        "direct_scpi_write": {
+            "doc": "write a SCPI command",
+            "request": [
+                {
+                    "name": "command",
+                    "type": "string"
+                }
+            ],
+            "response": "null"
+        },
         "get_config": {
             "doc": "Full configuration for the individual daemon as defined in the TOML file.\nThis includes defaults and shared settings not directly specified in the daemon-specific TOML table.\n",
             "origin": "is-daemon",

yaqd_scpi/scpi-set-continuous.toml

@@ -24,4 +24,8 @@ doc = "Units of position / destination."
 
 [config.visa_address]
 type = "string"
-doc = "VISA resource name."
+doc = "VISA resource name."
+
+[messages.direct_scpi_write]
+doc = "write a SCPI command"
+request = [{"name"="command", "type"="string"}]

yaqd_scpi/scpi-set-discrete.avpr

@@ -98,6 +98,16 @@
             "request": [],
             "response": "boolean"
         },
+        "direct_scpi_write": {
+            "doc": "write a SCPI command",
+            "request": [
+                {
+                    "name": "command",
+                    "type": "string"
+                }
+            ],
+            "response": "null"
+        },
         "get_config": {
             "doc": "Full configuration for the individual daemon as defined in the TOML file.\nThis includes defaults and shared settings not directly specified in the daemon-specific TOML table.\n",
             "origin": "is-daemon",

yaqd_scpi/scpi-set-discrete.toml

@@ -19,4 +19,8 @@ doc = "SCPI command, e.g. :SOUR1:FREQ"
 
 [config.visa_address]
 type = "string"
-doc = "VISA resource name."
+doc = "VISA resource name."
+
+[messages.direct_scpi_write]
+doc = "write a SCPI command"
+request = [{"name"="command", "type"="string"}]