diff --git a/ble_interface.py b/ble_interface.py
index b58a99e..70a086e 100644
--- a/ble_interface.py
+++ b/ble_interface.py
@@ -16,6 +16,7 @@ class ble_interface:
     CURRENT = "current"
     VOLTAGE = "volts"
     CONFIGURATION = "conf"
+    RANGE = "range"
     RFRSH_DELAY = "refresh_delay"
     ON_CONNECT = "on_connect"
 
@@ -28,6 +29,7 @@ class ble_interface:
         self.services: Dict[str, BleakGATTService] = {}
         self.handlers = {
             self.CURRENT: self.__current_meas_handler,
+            self.RANGE: self.__range_handler,
         }
 
     async def __connect(self):        
@@ -61,18 +63,21 @@ class ble_interface:
             
             if(s.uuid == normalize_uuid_str(myUUIDs.CONFIGURATION_SERVICE)):
                 self.services[self.CONFIGURATION] = s
+                
+            if(s.uuid == normalize_uuid_str(myUUIDs.METROLOGY_RANGE_SERVICE)):
+                self.services[self.RANGE] = s
     
     def connect(self):
         self.log.info("connecting")
 
         self.loop.create_task(self.__connect())
 
-    def subscribe_to(self, to: str):
-        self.loop.create_task(self.__subscribe_to(to))
+    def subscribe_to(self, to: str, char_uuid: str | None = None):
+        self.loop.create_task(self.__subscribe_to(to, char_uuid))
  
-    async def __subscribe_to(self, to: str):
+    async def __subscribe_to(self, to: str, char_uuid: str | None):
         self.log.info("subscribing to %s", to)
-        for c in self.services[to].characteristics:
+        for c in filter(lambda c: (not char_uuid) or (c.uuid == char_uuid), self.services[to].characteristics):
             await self.client.start_notify(c, self.handlers[to])
     
     def add_callback(self, id: str, callback):
@@ -93,9 +98,125 @@ class ble_interface:
         handle = next(i for i,c in enumerate(self.services[self.CURRENT].characteristics) if c.handle == char.handle)
 
         self.call_callback(self.CURRENT, handle, val)
-        if(self.CURRENT in self.callbacks):
-            for c in self.callbacks[self.CURRENT]:
-                c(self, handle, val)
+
+    def __range_handler(self, char: BleakGATTCharacteristic, data: bytearray):
+        val = struct.unpack("<i", data)[0]
+
+        self.call_callback(self.RANGE, val)
+        
+    async def get_refresh_delay(self) -> int:
+        s = self.services[self.CONFIGURATION]
+        c = s.get_characteristic(myUUIDs.SAMPLING_RATE_CHAR);
+        if(not c):
+            return -1
+        val = await self.client.read_gatt_char(c)
+        return struct.unpack("<I", val)[0]
+
+    async def get_zero_cali_nsamp(self) -> int:
+        s = self.services[self.CONFIGURATION]
+        c = s.get_characteristic(myUUIDs.ZERO_CALI_NSAMP);
+        if(not c):
+            return -1
+        val = await self.client.read_gatt_char(c)
+        return struct.unpack("<I", val)[0]
+
+    async def get_auto_range(self) -> bool:
+        s = self.services[self.RANGE]
+        c = s.get_characteristic(myUUIDs.AUTO_RANGE_CHAR);
+        if(not c):
+            return False
+        val = await self.client.read_gatt_char(c)
+        self.log.info(val)
+        return struct.unpack("<i", val)[0] != 0
+    
+    async def get_range(self) -> bool:
+        s = self.services[self.RANGE]
+        c = s.get_characteristic(myUUIDs.ELECTRIC_CURRENT_RANGE_CHAR);
+        if(not c):
+            return False
+        val = await self.client.read_gatt_char(c)
+        self.log.info(val)
+        return struct.unpack("<i", val)[0] != 0
+
 
     def update_refresh_delay(self, val: int):
-        pass
\ No newline at end of file
+        self.loop.create_task(self.__update_refresh_delay(val))
+
+    async def __update_refresh_delay(self, val: int):
+        s = self.services[self.CONFIGURATION]
+        c = s.get_characteristic(myUUIDs.SAMPLING_RATE_CHAR)
+        if(not c):
+            return
+
+        data = struct.pack("<I", val)
+        
+        await self.client.write_gatt_char(c, data)
+
+
+    def zero_cali(self):
+        self.loop.create_task(self.__zero_cali())
+
+    async def __zero_cali(self):
+        s = self.services[self.CONFIGURATION]
+        c = s.get_characteristic(myUUIDs.ZERO_CALI_CHAR)
+        if(not c):
+            return
+
+        data = struct.pack("<B", 1)
+        
+        await self.client.write_gatt_char(c, data)
+
+    def update_zero_cali_nsamp(self, val: int):
+        self.loop.create_task(self.__update_zero_cali_nsamp(val))
+
+    async def __update_zero_cali_nsamp(self, val: int):
+        s = self.services[self.CONFIGURATION]
+        c = s.get_characteristic(myUUIDs.ZERO_CALI_NSAMP)
+        if(not c):
+            return
+
+        data = struct.pack("<I", val)
+        
+        await self.client.write_gatt_char(c, data)
+
+    
+    def reset_offsets(self):
+        self.loop.create_task(self.__reset_offsets())
+
+    async def __reset_offsets(self):
+        s = self.services[self.CONFIGURATION]
+        c = s.get_characteristic(myUUIDs.ZERO_CALI_RESET)
+        if(not c):
+            return
+
+        data = struct.pack("<B", 1)
+        
+        await self.client.write_gatt_char(c, data)
+
+    
+    def update_auto_range(self, val: bool):
+        self.loop.create_task(self.__update_auto_range(val))
+
+    async def __update_auto_range(self, val: bool):
+        s = self.services[self.RANGE]
+        c = s.get_characteristic(myUUIDs.AUTO_RANGE_CHAR)
+        if(not c):
+            return
+
+        data = struct.pack("<B", val)
+        
+        await self.client.write_gatt_char(c, data)
+
+
+    def update_range(self, val: int):
+        self.loop.create_task(self.__update_range(val))
+
+    async def __update_range(self, val: int):
+        s = self.services[self.RANGE]
+        c = s.get_characteristic(myUUIDs.ELECTRIC_CURRENT_RANGE_CHAR)
+        if(not c):
+            return
+
+        data = struct.pack("<i", val)
+        
+        await self.client.write_gatt_char(c, data)
diff --git a/main.py b/main.py
index 3d941cf..cb97563 100644
--- a/main.py
+++ b/main.py
@@ -21,10 +21,37 @@ loop: asyncio.AbstractEventLoop
 device: ble_interface
 
 current_meas = {}
+max_current = 0
 start_time = None
 
+def clear_plot(sender, app_data):
+    logger.info("clear")
+    global current_meas
+    global start_time
+    global max_current
+    for d in current_meas:
+        current_meas[d] = []
+    start_time = None
+    max_current = 0
+    
 def on_connect_handler(device: ble_interface):
     device.subscribe_to(device.CURRENT)
+    device.subscribe_to(device.RANGE, normalize_uuid_str(myUUIDs.ELECTRIC_CURRENT_RANGE_CHAR))
+    loop.create_task(update_conf_values())
+
+async def update_conf_values():
+    refresh_rate = await device.get_refresh_delay()
+    dpg.set_value("refresh delay", refresh_rate)
+
+    zero_cali_nsamp = await device.get_zero_cali_nsamp()
+    dpg.set_value("zero_nsamp", zero_cali_nsamp)
+    
+    auto_range = await device.get_auto_range()
+    dpg.set_value("auto_range", auto_range)
+    
+    range = await device.get_range()
+    dpg.set_value("range", range)
+
 
 def current_meas_handler(device: ble_interface, input_handle: int, newval: int):
     value = newval
@@ -44,27 +71,59 @@ def current_meas_handler(device: ble_interface, input_handle: int, newval: int):
         current_meas[handle] = []
         dpg.add_line_series([], [], label=f"{handle}", parent="y_axis", tag=f"serie{handle}")
     
-    current_meas[handle].append(((time.monotonic_ns() - start_time) * 1e-9, value * 1e-6))
+    current_meas[handle].append(((time.monotonic_ns() - start_time) * 1e-9, value))
 
     dpg.set_value(f"serie{handle}", [ [v[0] for v in current_meas[handle]], [v[1] for v in current_meas[handle]] ])
-    # dpg.fit_axis_data("x_axis")
+    dpg.fit_axis_data("x_axis")
     # dpg.fit_axis_data("y_axis")
 
+    global max_current
+    max_current = max(max_current, newval)
+    dpg.set_axis_limits("y_axis", 0., 1.1 * max_current)
 
+    txt = ""
+    for h in current_meas:
+        if(len(current_meas[h]) == 0):
+            continue
+        txt += f"{h} : {current_meas[h][-1][1]} | "
+    dpg.set_value("last_current_values", txt)
+
+def range_changed_handler(device: ble_interface, val: int):
+    dpg.set_value("range", val)
+    
 def update_refresh_rate(sender, app_data):
     logger.info("refresh rate %d", app_data)
     device.update_refresh_delay(app_data)
+    
+def update_zero_nsamp(sender, app_data):
+    logger.info("nsamp %d", app_data)
+    device.update_zero_cali_nsamp(app_data)
+
+def set_auto_range(sender, app_data):
+    logger.info("auto range %d", app_data)
+    device.update_auto_range(app_data)
+
+def set_range(sender, app_data):
+    logger.info("set range %d", app_data)
+    device.update_range(app_data)
 
 async def init_gui():
     dpg.create_context()
     dpg.create_viewport()
     dpg.setup_dearpygui()
 
-    with dpg.window(label="Controls", pos = [0, 0], width = dpg.get_viewport_width(), height = 100):
+    with dpg.window(label="Controls", pos = [0, 0], width = 200, height = dpg.get_viewport_height()):
         dpg.add_button(label="Connect", callback=device.connect)
         dpg.add_input_int(label="Refresh Delay", callback=update_refresh_rate, on_enter=True, tag="refresh delay")
+        dpg.add_button(label="Zero", callback=device.zero_cali)
+        dpg.add_input_int(label="Zero nb sample", callback=update_zero_nsamp, on_enter=True, tag="zero_nsamp")
+        dpg.add_button(label="Reset offsets", callback=device.reset_offsets)
+        dpg.add_checkbox(label="Auto-range", callback=set_auto_range, tag="auto_range")
+        dpg.add_input_int(label="Range", callback=set_range, on_enter=True, tag="range")
         
-    with dpg.window(label="Graphs", pos = [0, 100], width = dpg.get_viewport_width(), height = 500):
+    with dpg.window(label="Graphs", pos = [200, 0], width = dpg.get_viewport_width()-200, height = dpg.get_viewport_height()):
+        dpg.add_button(label="Clear", callback=clear_plot)
+        dpg.add_text(label="Current", tag="last_current_values")
         with dpg.plot(label="Current", width = -1, height = -1):
             dpg.add_plot_legend()
 
@@ -72,7 +131,7 @@ async def init_gui():
             dpg.add_plot_axis(dpg.mvYAxis, label="y", tag="y_axis")
 
             dpg.set_axis_limits_auto("x_axis")
-            dpg.set_axis_limits_auto("y_axis")
+            # dpg.set_axis_limits_auto("y_axis")
 
     dpg.show_viewport()
     while dpg.is_dearpygui_running():
@@ -92,6 +151,7 @@ if __name__ == "__main__":
     device = ble_interface("84:F7:03:1B:C6:A2", loop, logger)
     device.add_callback(device.ON_CONNECT, on_connect_handler)
     device.add_callback(device.CURRENT, current_meas_handler)
+    device.add_callback(device.RANGE, range_changed_handler)
     
     loop.create_task(init_gui())
     loop.run_forever()
diff --git a/myUUIDs.py b/myUUIDs.py
index 71d2c36..7380ff7 100644
--- a/myUUIDs.py
+++ b/myUUIDs.py
@@ -6,6 +6,7 @@ VOLTAGE_CHAR = "2B18"
 SAMPLING_RATE_CHAR = "2C12"
 ZERO_CALI_CHAR = "2C13"
 ZERO_CALI_NSAMP = "2C14"
+ZERO_CALI_RESET = "2C16"
 ELECTRIC_CURRENT_RANGE_CHAR = "2AEF"
 AUTO_RANGE_CHAR = "2C15"
 CHAR_PRES_FORMAT = "2904"