An eMarker device for use in a USB type-C cable electrically connected between a first port and a second port, wherein the cable includes a configuration channel communication wire and a bus power wire (Vbus), and the eMarker device comprises: a first eMarker (60, 70) disposed near the first port and including a first active protection module (40, 71) coupled to the configuration channel communication wire; and a second eMarker (60b, 70b) disposed near the second port and including a second active protection module (40b, 71b) coupled to the configuration channel communication wire, the eMarker device characterized in that: only one of the first eMarker (60, 70) and the second eMarker (60b, 70b) is electrically connected to a first power pin (Vconn1) of the first port and a second power pin (Vconn2) of the second port, and the only one eMarker is the first eMarker (60, 70), the first active protection module (40, 71) which is coupled to the bus power wire (Vbus) having connections to a third power pin (p1a) of the first port and to a fourth power pin (p2a) of the second port, is configured to determine whether a first specified event happens according to a supply characteristic of the bus power wire (Vbus), and to raise a voltage of the configuration channel communication wire to a level higher than a predetermined open-circuit voltage to have one of the first port and the second port determine that the cable connected between the first port and the second port is detached from the other one of the first port and the second port when the first specified event happens in the cable, the second active protection module (40b, 71b) is configured to raise the voltage of the configuration channel communication wire to a level higher than the predetermined open-circuit voltage to have the one of the first port and the second port determine that the cable connected between the first port and the second port is detached from the other one of the first port and the second port when a second specified event happens in the cable near the second port. a first eMarker (60, 70) disposed near the first port and including a first active protection module (40, 71) coupled to the configuration channel communication wire; and a second eMarker (60b, 70b) disposed near the second port and including a second active protection module (40b, 71b) coupled to the configuration channel communication wire, the eMarker device characterized in that: only one of the first eMarker (60, 70) and the second eMarker (60b, 70b) is electrically connected to a first power pin (Vconn1) of the first port and a second power pin (Vconn2) of the second port, and the only one eMarker is the first eMarker (60, 70), the first active protection module (40, 71) which is coupled to the bus power wire (Vbus) having connections to a third power pin (p1a) of the first port and to a fourth power pin (p2a) of the second port, is configured to determine whether a first specified event happens according to a supply characteristic of the bus power wire (Vbus), and to raise a voltage of the configuration channel communication wire to a level higher than a predetermined open-circuit voltage to have one of the first port and the second port determine that the cable connected between the first port and the second port is detached from the other one of the first port and the second port when the first specified event happens in the cable, the second active protection module (40b, 71b) is configured to raise the voltage of the configuration channel communication wire to a level higher than the predetermined open-circuit voltage to have the one of the first port and the second port determine that the cable connected between the first port and the second port is detached from the other one of the first port and the second port when a second specified event happens in the cable near the second port. only one of the first eMarker (60, 70) and the second eMarker (60b, 70b) is electrically connected to a first power pin (Vconn1) of the first port and a second power pin (Vconn2) of the second port, and the only one eMarker is the first eMarker (60, 70), the first active protection module (40, 71) which is coupled to the bus power wire (Vbus) having connections to a third power pin (p1a) of the first port and to a fourth power pin (p2a) of the second port, is configured to determine whether a first specified event happens according to a supply characteristic of the bus power wire (Vbus), and to raise a voltage of the configuration channel communication wire to a level higher than a predetermined open-circuit voltage to have one of the first port and the second port determine that the cable connected between the first port and the second port is detached from the other one of the first port and the second port when the first specified event happens in the cable, the second active protection module (40b, 71b) is configured to raise the voltage of the configuration channel communication wire to a level higher than the predetermined open-circuit voltage to have the one of the first port and the second port determine that the cable connected between the first port and the second port is detached from the other one of the first port and the second port when a second specified event happens in the cable near the second port.