107-Arduino-UAVCAN

Arduino library for providing a convenient C++ interface for accessing UAVCAN (v1.0-beta) utilizing libcanard.

This library works for

• ArduinoCore-samd: Arduino Zero, MKR 1000, MKR WiFi 1010, Nano 33 IoT, MKR GSM 1400, MKR NB 1500, MKR WAN 1300/1310 ✔️
• ArduinoCore-mbed: Portenta H7, Nano 33 BLE, Nano RP2040 Connect, Edge Control ✔️
• arduino-esp32: ESP32 Dev Module, ESP32 Wrover Module, ... ✔️

Reference-Implementation UAVCAN on Arduino

• UAVCAN-GNSS-Node: A UAVCAN node with a GNSS sensor providing location data.
• UAVCAN-ToF-Distance-Sensor-Node: Demo firmware for UAVCAN ToF Distance Sensor Node utilizing 107-Arduino-UAVCAN.

Example

Note: Please be advised that the examples shipped with this library are to be considered minimal examples to get you started working with UAVCAN. They are known to violate section 2.1.2.2 Regulation of the UAVCAN 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., UAVCAN-GNSS-Node.

#include <ArduinoUAVCAN.h>
/* ... */
ArduinoUAVCAN uavcan(13, transmitCanFrame);
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) {
    uavcan.publish(hb);
    prev = now;
  }

  /* Transmit all enqeued CAN frames */
  while(uavcan.transmitCanFrame()) { }
}
/* ... */
bool transmitCanFrame(CanardFrame const & frame) {
  /* ... */
}

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/UAVCAN/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 clases to src/ArduinoUAVCANTypes.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 UAVCAN types listed in public_regulated_data_types:master will be accepted into this repository.