12-09-2017, 11:38 AM
In the past, CAN-based products used a standard CAN controller chip, a microprocessor with an integrated CAN interface, or a custom ASIC with a CAN interface for high-volume applications. Now, with advances in silicon technologies, a new option is readily available: Field Programmable Gate Arrays (FPGA). An FPGA is a gate array that can be programmed during production or later when deployed. They occur at a high volume, which reduces the individual cost of the device. FPGA vendors announce their largest multi-million-device "system gates". Although few applications really require them, they allow other products to be implemented. Large devices need the most advanced silicon processing technologies. Since each FPGA family comprises several members ranging from large to small door beads, small devices are available in the same technology. With the high gate density available in these advanced process technologies, even small devices provide sufficient resources for system integrations. Suddenly, small FPGAs offer solutions that were not available before and cost only a few dollars.
The design contains all the necessary features necessary to implement a high performance communication protocol. The CAN controller with a single bus line connection performs all the functions of the physical and data link layers. The application layer is provided by a microcontroller, to which the CAN controller is connected through a non-multiplexed, general purpose 8-bit bus. The CAN communication protocol describes the method by which information is passed between devices. It fits the open system interconnect model, which is defined in terms of layers. Each layer of a device apparently communicates with the same layer on another device. The actual communication is between adjacent layers on each device and the devices are only connected by the physical medium through the physical layer of the model. The CAN architecture defines the two lowest layers of the model: the data link and the physical layers. Application levels are linked to the physical environment by layers of several emerging protocols, dedicated to particular industrial areas plus any number of ownership schemes defined by individual users of the CAN.
The design contains all the necessary features necessary to implement a high performance communication protocol. The CAN controller with a single bus line connection performs all the functions of the physical and data link layers. The application layer is provided by a microcontroller, to which the CAN controller is connected through a non-multiplexed, general purpose 8-bit bus. The CAN communication protocol describes the method by which information is passed between devices. It fits the open system interconnect model, which is defined in terms of layers. Each layer of a device apparently communicates with the same layer on another device. The actual communication is between adjacent layers on each device and the devices are only connected by the physical medium through the physical layer of the model. The CAN architecture defines the two lowest layers of the model: the data link and the physical layers. Application levels are linked to the physical environment by layers of several emerging protocols, dedicated to particular industrial areas plus any number of ownership schemes defined by individual users of the CAN.