`nanopb-encode-decode`

:::warning [UNTESTED] native_sim build + run PASSED locally, but this has not been verified on real silicon (no bench / HiL sweep). :::

A protobuf message encode → buffer → decode round-trip with nanopb 0.4.9 (zlib licence) — protocol buffers sized for an MCU.

Source: examples/connectivity/nanopb-encode-decode/.

What it does

pb_encode() a DeviceStatus { int32 uptime_s; string device_id } into a caller-owned buffer.
pb_decode() it back into a fresh struct.
Asserts the round-trip.

Everything is in RAM and every buffer is caller-owned — nanopb never allocates.

:::note The generated sources are checked in device_status.pb.c / .pb.h are pre-generated and committed, because there is no protoc in this build environment. Do not hand-edit them — regenerate from the .proto instead. :::

Unlike most of the library examples, nanopb is a real fetched west module (modules/lib/nanopb), not a vendored stub. Its zephyr/module.yml declares cmake-ext / kconfig-ext glue that the SDK does not wire centrally, so the example's CMakeLists.txt compiles the runtime sources (pb_encode.c / pb_decode.c / pb_common.c) directly via ${ZEPHYR_NANOPB_MODULE_DIR}. libraries: [nanopb] emits CONFIG_ALP_NANOPB_SW=y.

`board.yaml`

libraries:
  - name: nanopb
    cores: [m55_hp]

som:
  sku: E1M-AEN801

preset: e1m-evk

cores:
  m55_hp:
    app: ./src
    peripherals: []

diagnostics:
  log_level: info

This example does no I/O — swap som.sku to any SoM/preset pair and it still builds; the round-trip is entirely in RAM.

Expected output

[nanopb-encode-decode] encoded 14 bytes
[nanopb-encode-decode] decoded uptime_s=42 device_id="e1m-aen801"
[nanopb-encode-decode] round trip OK
[nanopb-encode-decode] done

What it does​

board.yaml​

Expected output​

See also​

What it does

`board.yaml`

Expected output

See also