csyn

csyn is the CogniPilot synapse topic toolkit. One repo, two sides of the wire, one folder per artifact:

• zephyr/: the west module — a lock-free latest-sample topic store for embedded vehicles, with zenoh and native_sim UDP transports, a zros bridge, and csyn topic list/info/echo/hz/watch shell diagnostics. Topic payloads are rendered by the synapse_fbs-generated field-descriptor printer, so every fixed-layout topic prints without hand-written formatting code.
• rust/: the host-side csyn CLI, a ROS-like command-line tool for Synapse systems using Zenoh for transport (see rust/README.md).

Both sides speak the synapse_fbs schema through a pinned release of the same version: the Zephyr module pins the C release tarball in zephyr/CMakeLists.txt, while the CLI pins the synapse_fbs crate, which embeds the schema sources, compiled binary schemas, topic catalog, and generated decoder. Every topic (name, keyexpr, payload type, encoding, catalog id) resolves from the generated catalog, so the wire contract is locked by csyn rather than per application and nothing is vendored.

Zephyr module

Add csyn to your west manifest:

- name: csyn
  remote: cognipilot
  revision: main
  path: modules/lib/csyn

Enable it in prj.conf:

CONFIG_CSYN=y
CONFIG_CSYN_SHELL=y
CONFIG_CSYN_ZROS_BRIDGE=y

and pick a transport per board: CONFIG_CSYN_ZENOH=y (flight hardware) or CONFIG_CSYN_NATIVE_UDP=y (native_sim). Applications publish and subscribe through the zros topics declared in <csyn/csyn_zros.h>; the bridge mirrors them to the active transport.

Layout (everything for the module lives under zephyr/):

• zephyr/include/csyn/csyn.h — topic registry and store API
• zephyr/include/csyn/csyn_codec.h — payload decode/encode plus PWM/axis and quaternion/euler helpers
• zephyr/include/csyn/csyn_types.h — plain in-process types (rc channels, mocap rigid body, manual control)
• zephyr/include/csyn/csyn_zros.h — zros topic declarations vehicles use
• zephyr/src/ — store, codec, bridge, shell, and transports
• zephyr/{module.yml,Kconfig,CMakeLists.txt} — west integration and the pinned synapse_fbs release

Rust CLI

The host tool lives in rust/:

cd rust
cargo run -- topic list

Bags are standard MCAP files whose schema records carry the embedded synapse_fbs binary schemas, so recordings are self-describing for any MCAP tool. The legacy .csynbag format is retired.

Until synapse_fbs 0.3.0 is published to crates.io, build the CLI against a locally staged crate (cargo run -- ci in synapse_fbs stages it):

cargo build --config 'patch.crates-io.synapse_fbs.path="<synapse_fbs>/target/xtask/packages/rust"'

Testing

CI runs entirely on hosted GitHub runners with no hardware: twister builds and runs the module tests on native_sim (using the repo's own west.yml as a CI workspace manifest), and the CLI runs cargo fmt/clippy/test. Formatting is enforced with the Zephyr .clang-format and rustfmt. Board targets may be added to platform_allow for optional local twister runs, but must stay out of integration_platforms so CI never needs hardware.

west twister -T zephyr/tests -p native_sim --inline-logs   # Zephyr module
cd rust && cargo test                                      # host CLI

License

Apache-2.0