CanPS Standalone driver

Introduction

This page gives an overview of canps driver which is available as part of the Xilinx Vivado and SDK distribution.
This is common for both Zynq and ZynqMP.
For more information, please refer Chapter 20: Can Controller in Zynqmp Trm which includes links to the official documentation and resource utilization. 

Driver Sources

The source code for the driver is included with the Vitis Unified Software Platform installation, as well as being available in the Xilinx Github repository. 

Driver namePath in Vitis

Path in Github

canps

<Vitis Install Directory>/data/embedded/XilinxProcessorIPLib/drivers/canps

https://github.com/Xilinx/embeddedsw/tree/master/XilinxProcessorIPLib/drivers/canps

Note: To view the sources for a particular release, use the rel-version tag in github.  For example, for the 2020.1 release, the proper version of the code is: https://github.com/Xilinx/embeddedsw/tree/master/XilinxProcessorIPLib/drivers/canps

The driver source code is organized into different folders. The table below shows the canps driver source organization.

DirectoryDescription
srcDriver source files
examplesExample applications that show how to use the driver features
docProvides the API and data structure details
dataDriver .tcl and .mdd file

Driver Implementation

For a full list of features supported by this IP, please refer Chapter 20: Can Controller in Zynqmp Trm

Features

Controller Features:

  • Compatible with the ISO 11898 -1, CAN 2.0A, and CAN 2.0B standards
  • Standard (11-bit identifier) and extended (29-bit identifier) frames
  • Bit rates up to 1 Mb/s
  • Transmit message FIFO (TxFIFO) with a depth of 64 messages
  • Transmit prioritization through one high-priority transmit buffer (TxHPB
  • Watermark interrupts for TxFIFO and RxFIFO
  • Automatic re-transmission on errors or arbitration loss in normal mode
  • Receive message FIFO (RxFIFO) with a depth of 64 messages
  • Four Rx acceptance filters with enables, masks and IDs
  • Loop back and snoop modes for diagnostic applications
  • Mask able error and status interrupts
  • 16-Bit time stamping for receive message
  • Readable Rx/Tx error counters

Driver supported Features:

  • Supports Standard and extended frames
  • Supports Config, Sleep, Normal and snoop modes
  • Supports Acceptance filter configurations
  • Supports Polled and interrupt modes
  • Water mark interrupt support for both Tx and Rx FIFOs
  • Supports Transmit prioritization through one high-priority transmit buffer (TxHPB)

Known Issues and Limitations

  • None.


Example Applications

Refer to the driver examples directory for various example applications that exercise the different features of the driver. Each application is linked in the table below. The following sections describe the usage and expected output of the various applications.  These example applications can be imported into the Vitis IDE from the Board Support Package  settings tab.

Links to Examples

Examples Path:

https://github.com/Xilinx/embeddedsw/tree/master/XilinxProcessorIPLib/drivers/canps/examples

Test NameSource

Description

Polled

xcanps_polled_example.c

It configures the CAN controller in loop back mode with no interrupt enabled and verifies the data received with data sent
interruptxcanps_intr_example.cIt configures the CAN controller in loop back mode with interrupts enabled and verifies the data received with data sent
Watermarkxcanps_watermark_intr_example.cIt configures the CAN controller in loop back mode with rx and tx water mark interrupts enabled with some RX and TX threshold.

Example Application Usage

Canps polled mode test

https://github.com/Xilinx/embeddedsw/blob/master/XilinxProcessorIPLib/drivers/canps/examples/xcanps_polled_example.c
It configures the CAN controller in loop back mode with no interrupt enabled and verifies the data received with data sent
Polled Mode test::
CAN Polled Mode Example Test
Successfully ran CAN Polled Mode Example Test

Canps interrupt mode test

https://github.com/Xilinx/embeddedsw/blob/master/XilinxProcessorIPLib/drivers/canps/examples/xcanps_intr_example.c
It configures the CAN controller in loop back mode with interrupts enabled and verifies the data received with data sent
Interrupt Mode test:
CAN Interrupt Example Test
Successfully ran CAN Interrupt Example Test

Canps water mark interrupt test

https://github.com/Xilinx/embeddedsw/blob/master/XilinxProcessorIPLib/drivers/canps/examples/xcanps_watermark_intr_example.c
It configures the CAN controller in loop back mode with rx and tx water mark interrupts enabled with some RX and TX threshold.
Water Mark Test:
CAN Watermark Example Test
Successfully ran CAN Watermark Example Test

Change Log


Related Links