Add gate voltage to config (#331)

* add gate_voltage to config

* black formatting

* add changes to CONFIGURATION.md

* fix indent

software/CONFIGURATION.md

@@ -14,7 +14,8 @@ default configuration:
     "display_height": 32,
     "volts_per_octave": 1.0,
     "max_output_voltage": 10,
-    "max_input_voltage": 12
+    "max_input_voltage": 12,
+    "gate_voltage": 5
 }
 ```
 
@@ -29,3 +30,4 @@ default configuration:
   The hardware is capable of 10V maximum
 - `max_input_voltage` is an integer in the range `[0, 12]` indicating the maximum allowed voltage into the `ain` jack.
   The hardware is capable of 12V maximum
+- `gate_voltage` is an integer in the range `[0, 12]` indicating the voltage that an output will produce when `cvx.on()` is called

software/firmware/europi.py

@@ -576,6 +576,7 @@ def __init__(self, pin, min_voltage=MIN_OUTPUT_VOLTAGE, max_voltage=MAX_OUTPUT_V
         self._duty = 0
         self.MIN_VOLTAGE = min_voltage
         self.MAX_VOLTAGE = max_voltage
+        self.gate_voltage = clamp(europi_config["gate_voltage"], self.MIN_VOLTAGE, self.MAX_VOLTAGE)
 
         self._gradients = []
         for index, value in enumerate(OUTPUT_CALIBRATION_VALUES[:-1]):
@@ -597,7 +598,7 @@ def voltage(self, voltage=None):
 
     def on(self):
         """Set the voltage HIGH at 5 volts."""
-        self.voltage(5)
+        self.voltage(self.gate_voltage)
 
     def off(self):
         """Set the voltage LOW at 0 volts."""

software/firmware/europi_config.py

@@ -82,6 +82,11 @@ def config_points(cls):
                 range=range(1, 13),
                 default=12
             ),
+            configuration.integer(
+                name="gate_voltage",
+                range=range(1, 13),
+                default=5
+            ),
         ]
         # fmt: on