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Arduino library for providing a convenient C++ interface for accessing OpenCyphal.

107-Arduino-Cyphal

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This Arduino library implements the OpenCyphal (v1.0-beta) utilizing libcanard.

This library works for

Reference-Implementation OpenCyphal on Arduino

  • OpenCyphal-GNSS-Node: A OpenCyphal node with a GNSS sensor providing location data.
  • OpenCyphal-ToF-Distance-Sensor-Node: Demo firmware for OpenCyphal ToF Distance Sensor Node utilizing 107-Arduino-Cyphal.
  • SimLE-tenso-can: Firmware with multiple features for tensometer node on ESP32 utilizing its native CAN controller.
  • SimLE-sensor-bridge: CAN to I2C bridge for case specific communication with older PixHawk versions.

Example

Note: Please be advised that the examples shipped with this library are to be considered minimal examples to get you started working with OpenCyphal. They are known to violate section 2.1.2.2 Regulation of the OpenCyphal Specification due to their reliance on hard-coded port identifiers. A compliant implementation would instead provide configurable port-IDs and support the Register Interface (section 5.3 Application-layer functions). Fully compliant examples that implement reconfigurable port-IDs are shipped separately; e.g., OpenCyphal-GNSS-Node.

#include <107-Arduino-Cyphal.h>
/* ... */
Node node_hdl([](CanardFrame const & frame) { /* ... */ });
Heartbeat_1_0 hb;
/* ... */
void loop() {
  /* Update the heartbeat object */
  hb.uptime(millis() / 1000);
  hb.mode = Heartbeat_1_0::Mode::OPERATIONAL;

  /* Publish the heartbeat once/second */
  static unsigned long prev = 0;
  unsigned long const now = millis();
  if(now - prev > 1000) {
    node_hdl.publish(hb);
    prev = now;
  }

  /* Transmit all enqeued CAN frames */
  while(node_hdl.transmitCanFrame()) { }
}

Contribution

How to add missing wrappers

Step 1) Generate C header files from DSDL

Option A) Use nunavut/nnvg

  • Install nunavut: pip install nunavut (you will need a functional Python installation)
  • Get some DSDL
git clone https://github.com/OpenCyphal/public_regulated_data_types
  • Generate C header files from DSDL
nnvg --target-language c \
     --pp-max-emptylines=1  \
     --pp-trim-trailing-whitespace \
     --target-endianness=any \
     --enable-serialization-asserts \
     --outdir public_regulated_data_types/uavcan-header \
     public_regulated_data_types/uavcan

nnvg --target-language c \
     --pp-max-emptylines=1  \
     --pp-trim-trailing-whitespace \
     --target-endianness=any \
     --enable-serialization-asserts \
     --lookup public_regulated_data_types/uavcan \
     --outdir public_regulated_data_types/reg-header \
     public_regulated_data_types/reg

Option B) Use nunaweb

Step 2) Copy generated C header files to src/types
types/reg/drone/physics/electricity/
├── Power_0_1.h
├── PowerTs_0_1.h
├── Source_0_1.h
└── SourceTs_0_1.h
Step 3) Fix include path in generated C header files by prefixing it with <types/
-#include <uavcan/file/Path_1_0.h>
+#include <types/uavcan/file/Path_1_0.h>
...
-#include <reg/drone/physics/electricity/Power_0_1.h>
+#include <types/reg/drone/physics/electricity/Power_0_1.h>
Step 4) Manually implement wrapper classes in src/wrappers
wrappers/reg/drone/physics/electricity/
├── Power_0_1.hpp
├── PowerTs_0_1.hpp
├── Source_0_1.hpp
└── SourceTs_0_1.hpp
Step 5) Add the wrapper classes to src/NodeTypes.h
+#include "wrappers/reg/drone/physics/electricity/Power_0_1.hpp"
+#include "wrappers/reg/drone/physics/electricity/PowerTs_0_1.hpp"
+#include "wrappers/reg/drone/physics/electricity/Source_0_1.hpp"
+#include "wrappers/reg/drone/physics/electricity/SourceTs_0_1.hpp"
Step 6) Create PR to mainline your changes

Note: Only OpenCyphal types listed in public_regulated_data_types:master will be accepted into this repository.