Uploaded September 2012 | Updated September 2026, 1 week ago
What is CAN?
Controller Area Network (CAN) is a serial network that was originally designed for the automotive industry, but has also become a popular bus in industrial automation as well as other applications. The CAN bus is primarily used in embedded systems, and as its name implies, is the network established among microcontrollers. It is a two-wire, half duplex, high-speed network system and is well suited for high speed applications using short messages. Its robustness, reliability and the large following from the semiconductor industry are some of the benefits with CAN.
FullCAN
FullCAN is used in more expensive, high performance CAN controllers and microcontrollers. The FullCAN controller has a set of buffers called mailboxes. On initialization, each mailbox is assigned an identifier and is set to transmit or receive.
When the CAN controller receives a message it checks the mailboxes in order to see is there is a receive mailbox with the same identifier as the message. If such a mailbox is found, the message is stored in it and the host controller is notified. Otherwise the message is discarded.
When transmitting a message the message length and data is written to the transmit mailbox with the correct identifier.
If a remote message is received the controller checks the remote identifier against the transmit mailboxes. If a match is found, the controller automatically sends a message with the identifier and data contained in that mailbox. This means that the microcontroller gets a lower load, and that the software does not have to handle remote messages. However, if the mailbox has not been updated in a long time, the information sent to the network will be old. This have to be considered when writing the software.
With a FullCAN controller it is possible to filter out only the exact message types that are interesting. This type of controller will therefore give a lower load on the host microcontroller. However, the number of mailboxes are limited. The largest number of mailboxes present in a CAN controller today is ???.
With some controllers it is possible to reconfigure the mailboxes dynamically. However, that does not completely solve the problem. Therefore some controllers are mixed CAN controllers, that is they have mailboxes, but also BasicCAN buffers.
FullCAN controllers have support for automatically answering remote frames. This will decrease the load on the host microcontroller or processor, but may also mean that old information is sent. It is very important to take this into consideration when writing your application.
CAN can theoretically link up to 2032 devices (assuming one node with one identifier) on a single network. However, due to the practical limitation of the hardware (transceivers), it can only link up to110 nodes (with 82C250, Philips) on a single network. It offers high-speed communication rate up to 1 Mbits/sec thus allows real-time control. In addition, the error confinement and the error detection feature make it more reliable in noise critical environment.
LInk :- hem.bredband.net/stafni/developer/CAN.htm
CAN bus (for controller area network) is a vehicle bus standard designed to allow microcontrollers and devices to communicate with each other within a vehicle without a host computer.
CAN bus is a message-based protocol, designed specifically for automotive applications but now also used in other areas such as industrial automation and medical equipment.
Development of CAN bus started originally in 1983 at Robert Bosch GmbH.[1] The protocol was officially released in 1986 at the Society of Automotive Engineers (SAE) congress in Detroit, Michigan. The first CAN controller chips, produced by Intel and Philips, came on the market in 1987. Bosch published the CAN 2.0 specification in 1991.
CAN bus is one of five protocols used in the OBD-II vehicle diagnostics standard. The OBD-II standard has been mandatory for all cars and light trucks sold in the United States since 1996, and the EOBD standard has been mandatory for all petrol vehicles sold in the European Union since 2001 and all diesel vehicles since 2004.
en.wikipedia.org/wiki/CAN_bus
-~-~~-~~~-~~-~-
Please watch: "Lifi Communication by Arduino UNO Download Project"
youtube.com/watch?v=c4gC8dbaiZg
-~-~~-~~~-~~-~-
What is CAN?
Controller Area Network (CAN) is a serial network that was originally designed for the automotive industry, but has also become a popular bus in industrial automation as well as other applications. The CAN bus is primarily used in embedded systems, and as its name implies, is the network established among microcontrollers. It is a two-wire, half duplex, high-speed network system and is well suited for high speed applications using short messages. Its robustness, reliability and the large following from the semiconductor industry are some of the benefits with CAN.
FullCAN
FullCAN is used in more expensive, high performance CAN controllers and microcontrollers. The FullCAN controller has a set of buffers called mailboxes. On initialization, each mailbox is assigned an identifier and is set to transmit or receive.
When the CAN controller receives a message it checks the mailboxes in order to see is there is a receive mailbox with the same identifier as the message. If such a mailbox is found, the message is stored in it and the host controller is notified. Otherwise the message is discarded.
When transmitting a message the message length and data is written to the transmit mailbox with the correct identifier.
If a remote message is received the controller checks the remote identifier against the transmit mailboxes. If a match is found, the controller automatically sends a message with the identifier and data contained in that mailbox. This means that the microcontroller gets a lower load, and that the software does not have to handle remote messages. However, if the mailbox has not been updated in a long time, the information sent to the network will be old. This have to be considered when writing the software.
With a FullCAN controller it is possible to filter out only the exact message types that are interesting. This type of controller will therefore give a lower load on the host microcontroller. However, the number of mailboxes are limited. The largest number of mailboxes present in a CAN controller today is ???.
With some controllers it is possible to reconfigure the mailboxes dynamically. However, that does not completely solve the problem. Therefore some controllers are mixed CAN controllers, that is they have mailboxes, but also BasicCAN buffers.
FullCAN controllers have support for automatically answering remote frames. This will decrease the load on the host microcontroller or processor, but may also mean that old information is sent. It is very important to take this into consideration when writing your application.
CAN can theoretically link up to 2032 devices (assuming one node with one identifier) on a single network. However, due to the practical limitation of the hardware (transceivers), it can only link up to110 nodes (with 82C250, Philips) on a single network. It offers high-speed communication rate up to 1 Mbits/sec thus allows real-time control. In addition, the error confinement and the error detection feature make it more reliable in noise critical environment.
LInk :- hem.bredband.net/stafni/developer/CAN.htm
CAN bus (for controller area network) is a vehicle bus standard designed to allow microcontrollers and devices to communicate with each other within a vehicle without a host computer.
CAN bus is a message-based protocol, designed specifically for automotive applications but now also used in other areas such as industrial automation and medical equipment.
Development of CAN bus started originally in 1983 at Robert Bosch GmbH.[1] The protocol was officially released in 1986 at the Society of Automotive Engineers (SAE) congress in Detroit, Michigan. The first CAN controller chips, produced by Intel and Philips, came on the market in 1987. Bosch published the CAN 2.0 specification in 1991.
CAN bus is one of five protocols used in the OBD-II vehicle diagnostics standard. The OBD-II standard has been mandatory for all cars and light trucks sold in the United States since 1996, and the EOBD standard has been mandatory for all petrol vehicles sold in the European Union since 2001 and all diesel vehicles since 2004.
en.wikipedia.org/wiki/CAN_bus
-~-~~-~~~-~~-~-
Please watch: "Lifi Communication by Arduino UNO Download Project"
youtube.com/watch?v=c4gC8dbaiZg
-~-~~-~~~-~~-~-
