So. Now I solved the problem: After a sudo apt-get remove --purge evok && sudo apt-get update && sudo apt-get upgrade && sudo apt-get install evok and with this new configuration in the evok.conf I got it: [EXTENSION_1] global_id = 2 ; Mandatory, REQUIRED TO BE UNIQUE device_name = xG18 ; Mandatory modbus_uart_port = /dev/extcomm/0/0 ; Mandatory ;neuron_uart_circuit = 1_01 ; Optional allow_register_access = True ; Optional address = 1 ; Optional, scan_frequency = 10 ; Optional, scan_enabled = True ; Optional, ;baud_rate = 19200 ; Optional ;parity = N ; Optional, ;stop_bits = 1 ; Optional