USB for Modbus RTU
by therealegu from LinuxQuestions.org on (#6QFTS)
Hello,
I am using libmodbus (C library for Modbus communication) in order to communicate with a device over Modbus RTU. The device in question has an RJ45 port which accepts RS422 or RS485. The libmodbus library requires me to specify a serial port (e.g. /dev/ttyUSB1) when setting up the connection. I tried using a simple USB to Ethernet dongle adapter, but this is not showing up as /dev/ttyUSB1, or any other USB device that I am aware of. This is the result of sudo dmesg:
Code:[ 1213.124032] usb 3-1: new high-speed USB device number 7 using xhci_hcd
[ 1213.257211] usb 3-1: New USB device found, idVendor=0bda, idProduct=8152, bcdDevice=20.00
[ 1213.257223] usb 3-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 1213.257227] usb 3-1: Product: USB 10/100 LAN
[ 1213.257230] usb 3-1: Manufacturer: Realtek
[ 1213.257233] usb 3-1: SerialNumber: 00E04C4624A8
[ 1213.375668] r8152-cfgselector 3-1: reset high-speed USB device number 7 using xhci_hcd
[ 1213.531321] r8152 3-1:1.0: skip request firmware
[ 1213.557262] r8152 3-1:1.0 eth0: v1.12.13
[ 1213.575563] r8152 3-1:1.0 enx00e04c4624a8: renamed from eth0What type of USB to RJ45 adapter do I need to get that will show up as a USB device?
I am using libmodbus (C library for Modbus communication) in order to communicate with a device over Modbus RTU. The device in question has an RJ45 port which accepts RS422 or RS485. The libmodbus library requires me to specify a serial port (e.g. /dev/ttyUSB1) when setting up the connection. I tried using a simple USB to Ethernet dongle adapter, but this is not showing up as /dev/ttyUSB1, or any other USB device that I am aware of. This is the result of sudo dmesg:
Code:[ 1213.124032] usb 3-1: new high-speed USB device number 7 using xhci_hcd
[ 1213.257211] usb 3-1: New USB device found, idVendor=0bda, idProduct=8152, bcdDevice=20.00
[ 1213.257223] usb 3-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 1213.257227] usb 3-1: Product: USB 10/100 LAN
[ 1213.257230] usb 3-1: Manufacturer: Realtek
[ 1213.257233] usb 3-1: SerialNumber: 00E04C4624A8
[ 1213.375668] r8152-cfgselector 3-1: reset high-speed USB device number 7 using xhci_hcd
[ 1213.531321] r8152 3-1:1.0: skip request firmware
[ 1213.557262] r8152 3-1:1.0 eth0: v1.12.13
[ 1213.575563] r8152 3-1:1.0 enx00e04c4624a8: renamed from eth0What type of USB to RJ45 adapter do I need to get that will show up as a USB device?