CAN Simulation for ARM

The Crossware ARM Development Suite is able to simulate the CAN controller peripherals of the Philips LPC2119, LPC2129 and LPC2194 chips.

It does this by connecting to a simulated CAN bus.

Simulating CAN controllers each send a 'bit stream' to the simulated CAN bus. The CAN bus superimposes all of the received bit streams, with dominant bits winning, and sends the resulting bit stream back to each peripheral. In this way, the peripherals are able to truely arbitrate for the right to transmit, and will detect bus errors, stuff errors, etc.

The image on the left shows the result of a transmission from the simulating CAN1 controller of an LPC2129. Since this CAN controller is the only item connected to the CAN bus, it did not receive an ACK to it's transmission. It has therefore transmitted an error flag and is attempting a retransmission. It will carry on like this (going 'error passive' at the appropriate point) unless another item connects to the CAN bus and gives an acknowledgement.

The Philips LPC2119, LPC2129 and LPC2194 chips have multiple CAN controllers and so it is possible to transmit messages between these CAN controllers via the CAN bus. In addition, it is possible to run multiple simulations on multiple PC's. They can connect to the simulating CAN bus across the LAN and so exchange messages with each other.

In addition the CAN bus application itself allows 'components' to be connected to the bus. These components will automatically respond as receivers but can also be configured to transmit predefined messages, respond to specific received messages, and so on, making it easy to set up a complete simulating CAN system.

By default, the CAN bus application simulates a single bus. However it can easily be configured to support additional buses. One CAN controller of a simulating ARM chip can then connect to one bus while another connects to a different bus. This allows the software for a CAN 'hub' to be tested without any hardware.

The Crossware ARM Development Suite simulates all modes of the Philips CAN controllers including Full CAN mode. The Crossware Code Creation Wizards will also create code for the acceptance filter as well as the other aspects of the CAN controllers. It is therefore possible to have a simulating CAN system transmitting and receiving in minutes and without a single line of code having to be manually written.

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