defined start bit followed by six fields of frame bits Data frame starts after first detecting
that dominant state is not present at the CAN line with logic 1 (R state) to 0 (D state
transition) for one serial bit interval
٠ After start bit, six fields starting from arbitration field and ends with seven logicOs end-
field

٠ 3-bit minimum inter frame gap before next start bit (R— D transition) occurs

CAN Protocol defined frame bits

Start bit R to D transition 7 | 15-bit CRC. 1-bit delimiter
12-bit arbitration field 11- 1-bit ACK slot. 1-bit delimiter
bit identifier. RTR bit 1-bit ACK slot, 1-bit delimite1
6-bit Control field ஊ | 7 bits 0000000 for frame end

0- 64 bits Data length code

Data frame ‏ح‎ | 3-bit minimum
State (standard 11 bit inter frame gap

R (Recessive)
D (Dominant)

Protocol defined First field in frame bits _
First field of 12 bits -'arbitration field.

_ 11-bit destination address and RTR bit (Remote Transmission Request

-Destination device address specified in an11-bit sub-field and whether the data byte being sent
is a data for the device or a request to the device in 1-01 sub-field.

ட Maximum 211 devices can connect a CAN controller in case of 11-bit address fieldstandard1 1-
bit address standard CAN

_ identifies the device to which data is being sent or request is being made.

_ When RTR bit is at '1', it means this packet is for the device at destination address. If this bit is
at'0' (dominant state) it means, this packet is a request for the data from the device.

Protocol defined frame bits Second field _Second

field of 6 bits-control fields.

The first bit is for the identifier’s extension.