diff --git a/tests/query_device.py b/tests/query_device.py
index 5eb2834..b63a0e5 100755
--- a/tests/query_device.py
+++ b/tests/query_device.py
@@ -22,10 +22,14 @@ Read only CO2 register from sensor 123, baudrate 4800:
     {argv[0]} 123 4800 read CO2
 Read CO2, T_SHT4x and RH_SCD4x from sensor 222, default baudrate:
     {argv[0]} 222 read CO2 T_SHT4x RH_SCD4x
+Read register 30010 from sensor 247, default baudrate:
+    {argv[0]} 247 read 30010
+Read registers 30011, 30012, 30020 from sensor 247, baudrate 19200:
+    {argv[0]} 247 19200 read 30011 30012 30020
 Turn LED off for sensor 247, baud 115200:
-    {argv[0]} 247 115200 write 0 LED_on_register
-Set brightness of all connected sensors to 50%:
-    {argv[0]} 0 write 50 LED_brightness_register
+    {argv[0]} 247 115200 write LED_on 0
+Set brightness of all connected sensors to 50%, default baudrate (broadcast message):
+    {argv[0]} 0 write LED_brightness 50
 ''')
 
 # default values
@@ -84,7 +88,7 @@ if action != 'read' and action != 'write' and action != 'all' and action != 'res
     print(f'Unknown action {action}')
     exit(-4)
 if action == 'write' and value == None:
-    print(f'Action "write" needs value"')
+    print(f'Action "write" needs value')
     exit(-5)
 if action == 'write' and len(register_number) + len(register_name) != 1:
     print(f'Action "write" needs exactly one register to write to')
@@ -106,13 +110,16 @@ if action == 'write':
     print(f'Value to be written: {value}')
 # open device
 s = Sensor(address=addr, baudrate=baudrate)
+all_registers = Sensor.input_registers.copy()
+all_registers.update(Sensor.holding_registers)
+all_register_numbers = {}
+for name, number in all_registers.items():
+    all_register_numbers[number] = name
 if action == 'read' or action == 'all':
     print('---- Register readout ----')
     for register in register_name + register_number:
         if isinstance(register, str):
             reg_name = register
-            all_registers = Sensor.input_registers.copy()
-            all_registers.update(Sensor.holding_registers)
             if reg_name in all_registers:
                 reg_number = all_registers[reg_name]
             else:
@@ -120,13 +127,13 @@ if action == 'read' or action == 'all':
                 exit(-7)
         else:
             reg_number = register
-            reg_name = ''
+            # try reverse lookup
+            reg_name = all_register_numbers[reg_number] if reg_number in all_register_numbers else ''
         try:
-            result = s.read_register(reg_number)
+            result = int(s.read_register(reg_number))
         except:
-            print(f'{reg_number : <10} {"N/A" : <10} Failed to read register')
-            continue
-        print(f'{reg_number : <10} {int(result) : <10} {reg_name}')
+            result = 'N/A'
+        print(f'{reg_number : <10} {result : <10} {reg_name}')
 elif action == 'write':
     if len(register_name) > 0:
         if register_name[0] not in Sensor.holding_registers: