Changes i2c bus definition to enable second i2c bus for MUX boards

config.py

@@ -25,7 +25,7 @@ OHMPI_CONFIG = {
 
     'board_version': 'mb.2023.0.0',#,'22.10',
     'mcp_board_address': 0x21,
-    'i2c_mux_address': 2,  # 2 if on same bus as the measurement board, 4 if additional bus
+    'i2c_mux_address': 4,  # 2 if on same bus as the measurement board, 4 if additional bus
     'vmn_hardware_offset': 2502, # offset for the ads channel U0 voltage
     
 }  # TODO: add a dictionary with INA models and associated gain values