bit 0 = "overrun station fault": corresponds to loss of a MAC symbol while receiving – this is linked to the receiver reacting too slowly.

bit 1 = "message refusal fault": indicates that a message with acknowledgment was refused, or that it was not acknowledged in the first place. receiving MAC.

bit 2 = "interrupt variable refusal fault".

bit 3 = "underrun station fault": corresponds to the station being unable to respect transfer speed on the network.

bit 4 = "physical layer fault": corresponds to a prolonged transmission absence in the physical layer.

bit 5 = "non-echo fault": corresponds to a fault which occurs when the transmitter is currently sending, with a transmission current in the operating range, and when at the same time there is detection of an absence of signal on the same channel.

bit 6 = "talking fault": corresponds to a fault whereby the transmitter is controlling the line for longer than the maximum set operating limit. This fault is caused, for example, by deterioration of the modulator, or by a faulty data link layer.

bit 7 = "undercurrent fault": corresponds to a fault whereby the transmitter generates, when solicited, a current weaker than the minimum set operating limit. This fault is caused by increased line impedance (e.g. open line, etc.).

bit 8 = "pierced frame fault": indicates that a pause has been received in the frame body, after identifying a delimiter at the start of the frame, and before identifying a delimiter at the end of the frame. The appearance of a pause in normal operating conditions takes place after a delimiter has been identified at the end of a frame.

bit 9 = "Receiving frame CRC fault": indicates that the CRC calculated on a normally received frame and the CRC contained within this frame have different values.

bit 10 = "Receiving frame code fault": indicates that certain symbols, belonging exclusively to delimitation sequences at the start and end of frames, have been received within the body of the frame.

bit 11 = "received frame length fault": more than 256 bytes have been received for the frame body.

bit 12 = "unknown frame type received": within the frame body, the first byte identifies the type of frame link. A set number of frame types are defined in the WorldFip standard link protocol. Any other code found within a frame is therefore an unknown frame type.

bit 13 = "a truncated frame has been received": a frame section is recognized by a sequence of symbols delimiting the end of the frame, while the destination station awaits the arrival of a delimiter sequence for the start of the frame.

bit 14 = "unused, non-significant value".

bit 15 = "unused, non-significant value"