Can bus interview questions?

Which one is true about CAN bus?

CAN protocol is a message-based protocol, not an address based protocol. This means that messages are not transmitted from one node to another node based on addresses. … All nodes in the system receive every message transmitted on the bus (and will acknowledge if the message was properly received).

What is a CAN bus problem?

CANBUS is a high speed network which requires high quality wiring in order to operate properly. As such, it is sensitive to improper wiring. The majority of CANBUS communication problems are caused by poor wiring, incorrect termination, or the use of multiple frequencies on the same bus.

What is CAN bus and how it works?

The CAN bus system enables each ECU to communicate with all other ECUs – without complex dedicated wiring. … The broadcasted data is accepted by all other ECUs on the CAN network – and each ECU can then check the data and decide whether to receive or ignore it.

Can standard can and extended can coexist in the same network who will win arbitration if first arbitration field is the same?

Can Standard CAN and extended CAN coexist in the same network? … In extended frame format the IDE bit distinguish between standard and extended CAN. IDE bit is dominant(1) for the Standard frame and recessive for the extended frame.so standard frame will win arbitration if both have same 1st identifier field(11-bit).

HOW CAN bus works?

Devices on a CAN bus are called “nodes.” Each node consists of a CPU, CAN controller, and a transceiver, which adapts the signal levels of both data sent and received by the node. All nodes can send and receive data, but not at the same time. Nodes cannot send data directly to each other.

CAN error types?

Types of Error In CAN Protocol

In each CAN controller, it will have an error detection module that can detect the errors as: Bit Error. ACK Error. Stuff Error.

How do you diagnose a CAN bus system?

CAN you repair CAN bus wiring?

If the CAN bus line(s) are repaired, renew all the twisted wires between the end connectors. If the wiring harness is partially repaired, or only CAN_L or CAN_H line is repaired, noise suppression is deteriorated, causing a communication error.

How do I test a CAN bus with a multimeter?

So if the battery is disconnected. It’s ideal to how the battery disconnected. You connect your

CAN bus speed?

The maximum speed of a CAN bus, according to the standard, is 1 Mbit/second. Some CAN controllers will nevertheless handle higher speeds than 1Mbit/s and may be considered for special applications. Low-speed CAN (ISO 11898-3, see above) can go up to 125 kbit/s.

WHY CAN protocol is used?

The CAN protocol eliminates the need for excessive wiring by allowing electronic devices to communicate with each other along a single multiplex wire that connects each node in the network to the main dashboard.

Where is the CAN bus located?

Typical places to pick up CAN include the ABS system (look for a pair of twisted wires, but ignore the four wheel speed wires) or on the back of the dashboard (look for a pair of twisted wires). If the vehicle does have CAN Bus on the OBD connector, it will normally be on Pins 6 and 14 as indicated below.

Why CAN is having 120 ohms at each end Mcq?

Why Can Is Having 120 Ohms At Each End? Answer : To minimize the reflection reference, to reduce noise. To ensure that reflection does not cause communication failure, the transmission line must be terminated.

CAN bus is used for connecting?

CAN is a multi-master serial bus standard for connecting electronic control units (ECUs) also known as nodes (automotive electronics is a major application domain). Two or more nodes are required on the CAN network to communicate.

What is the order of standard CAN frame?

The CAN data frame is composed of seven fields: Start of frame (SOF), arbitration, control, data, cyclical redundancy check (CRC), acknowledge (ACK) and end of frame (EOF).