CAN

Every sub-step is one bit. The bus idles recessive, and the SOF is the first dominant bit.

Setting

Setting	Options	Default
Dominant level	Low, High	Low

A CAN bus idles recessive. On a transceiver pin that is the high level, so the dominant is low.

Field	What it is
SOF	Start of frame: one dominant bit
ID	11-bit identifier. The lower it is, the higher the priority
SRR	Takes the place of RTR in extended frames. Always recessive
IDE	Dominant: standard frame. Recessive: extended frame
Extended ID	The 18 bits that complete the 29-bit identifier
RTR	Dominant: data frame. Recessive: remote request
r1 / r0	Reserved bits, sent dominant
DLC	How many data bytes follow (0 to 8)
Data	The payload bytes
CRC	15 check bits over everything before it
CRC delimiter	One recessive bit
ACK	Any node that received the frame correctly pulls it dominant
ACK delimiter	One recessive bit
EOF	End of frame: 7 recessive bits
IFS	Interframe space: 3 recessive bits
Stuff bit	Added by the protocol after 5 equal bits; carries no information
Error flag	6 or more dominant bits in a row
Error delimiter	8 recessive bits

The reader computes the CRC and compares it with the drawn one, and checks the bit stuffing, the delimiters and the framing.

Label	What did not add up
Stuff error	Missing stuff bit: 6 equal bits in a row
Incomplete	The frame ends before it is complete
CRC error	The CRC does not match; the message gives the computed value
No ACK	Nobody acknowledged: the ACK slot stayed recessive
CRC delimiter	The CRC delimiter must be recessive
ACK delimiter	The ACK delimiter must be recessive
EOF error	End of frame must be 7 recessive bits
SRR dominant	In an extended frame the SRR must be recessive
Reserved bit	Reserved bits must be dominant
DLC > 8	DLC is over 8; 8 data bytes are sent anyway
Error flag	There is an error flag on the bus

Each frame is summed up in one line with the identifier and the essentials:

With nothing drawn, the status box explains:

No frame on this channel yet. Each sub-step is one bit: the bus idles recessive and the SOF is the first dominant bit.