3. Adapter in use
3.1 Connect to USB
USBCAN-I Pro adapter can support to the USB2.0 full speed protocol specification,compatible USB1.1.
When driver and software have been installed, connect the adapter to the USB interface, a new USBCAN device named “GC – Tech USBCAN Device” can be found in the PC Device manager. If there is no “!” or ”?” mark that the device run fine.
3.2 Connect to CAN
USBCAN-I Pro adapter connect to CAN-Bus as chapter 2.3, CAN_H toCAN_H,CAN_L to CAN_L.
The CAN bus network adopts topological structure, only the two furthest terminal need to connect 120Ω terminal resistance between CAN_H and CAN_L. For branch connection, its length should not be more than 3m. CAN-bus nodes connection as shown in figure 3.1

Note: the CAN-bus cable can use ordinary twisted-pair cable, shielded twisted-pair cable. Theory of the maximum communication distance depends on the bus baud rate, Their relationship as shown in the Table 3.1.

3.3 CAN-Bus terminal resistance
In order to improving the communication reliability and eliminating CAN-bus terminal reflection, the two furthest terminal need to connect terminal resistance between CAN_H and CAN_L as shown in figure 3.2. Terminal resistance values determined by the characteristic impedance of the cables. Such as, the characteristic impedance is 120Ω.

Note: USBCAN-I Pro adapter has integrated one 120Ω terminal resistance, users can choose whether enable.
3.4 System LED
USBCAN-I Pro adapter with one PWR indicator, one SYS indicator, one TX indicator one RX indicator to indicate the adapter status. More functions are shown in table 3.2 and 3.3.
When USBCAN-I Pro adapter power on, PWR and SYS light, indicates the adapter has power supply, the system is initialized; Otherwise, a system power failure or system errors has exist.
When USB-Bus data transfer, SYS indicator will blinking.
When CAN-Bus data transceiver, the corresponding TX or RX will blinking.