set power with percentage (#104)

* set power with percentage

* set power with value or percentage

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Co-authored-by: Damien Albisson <UF205DAL@net.elsys-design.com>

panduza/interfaces/blc.py

@@ -87,10 +87,15 @@ def set_mode_constant_power(self):
     def set_mode_constant_current(self):
         self.mode.value.set("constant_current")
 
-    # Set power value
-    def set_power_goal_point(self, value):
+    # Set power value directly with value
+    def set_power_value(self, value):
         self.power.value.set(value)
 
+    # Set power value with percentage (0% to 100%)
+    def set_power_with_percentage(self, percentage):
+        value_with_percentage = (1/100) * percentage * self.power.max.get()
+        self.power.value.set(value_with_percentage)
+
     def get_power_min_value(self):
         return self.power.min.get()