Indicate if the link status of port is Tx only.
The target is encoded
as:
Byte 1: the octet specifies a set of eight Chassis, Chassis 0 through 7
Byte 2~3: each octet specifies a set of eight slots, with the
first octet specifying slots 1 through 8 and the second
octet specifying slots 9 through 16.
Byte 4: reserved
Byte 5: Each bit in the octet specifies a port from MSB to LSB.
for example: 32(hex) = 50(dec) = 00110010(bin) means the port 3, 4 and 7.