Lantronix DSTni-EX manual CANbus Analysis, Arbitration Lost Capture Register

CANbus Analysis

Three additional registers are provided for advanced analysis of a CAN system. These registers include arbitration lost and error capture registers, as well as a CANbus frame reference register that contains information about the CANbus state and the physical Rx and TX pins.

Arbitration Lost Capture Register

The Arbitration Lost Capture register captures the most recent arbitration loss event with the frame reference pointer.

Table 5-60. Arbitration Lost Capture Register

BIT	15	14	13	12	11	10	9	8	7		6	5	4	3	2	1	0
OFFSET								76h
FIELD
		///		FR4	FR3	FR2	FR1	FR0		///		FRB5	FRB4	FRB3	FRB2	FRB1	FRB0
RESET	0	0	0	0	0	0	0	0	0		0	0	0	0	0	0	0
R/W	R/W	R/W	R/W	R/W	R/W	R/W	R/W	R/W	R/W		R/W	R/W	R/W	R/W	R/W	R/W	R/W

	Table 5-61. Arbitration Lost Capture Register Definitions
Bits	Field Name	Description
15:13	///	Reserved
12:8	FR[4:0]	frame_ref_Field
		This is the frame reference a incoming or outgoing CAN message.
		Values are:
		00000	= stopped
		00001	= synchronize
		00101	= interframe
		00110	= bus_idle
		00111	= start_of_frame
		01000	= arbitration
		01001	= control
		01010= data
		01011	= crc
		01100	= ack
		01101	= end_of_frame
		10000	= error_flag
		10001	= error_echo
		10010	= error_del:
		11000	= overload_flag
		11001	= overload_echo
		11010	= overload_del
		Other codes are not used.
7:6	///	Reserved
5:0	FRB[5:0]	frame_ref_bit_nr
		A 6-bit vector that counts the bit numbers in one field.
		Example: if field = “data” = “01010”, “bit_nr” = “000000”, and
		“tx_mode” = ‘1’, it indicates that the first data bit is being
		transmitted.

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