[lestarch-autobot]

Related Issue(s)	none — requested by @LeStarch; follows #5360 (cFS) and the Zephyr external-repo workflows
Has Unit Tests (y/n)	n (CI workflow only)
Documentation Included (y/n)	n
Generative AI was used in this contribution (y/n)	AI

---

Change Description

Adds .github/workflows/ext-fprime-samd-reference.yml: the baremetal-SAMD21 counterpart of ext-fprime-zephyr-reference.yml. It cross-builds fprime-community/fprime-samd-reference (CuriosityReference, ATSAMD21G17D Cortex-M0+) against the PR's F Prime with fprime-ci on ubuntu-22.04, archives the result, then on the apple-ci hardware runner flashes it to a Microchip SAMD21 Curiosity Nano over the on-board nEDBG (OpenOCD) and runs the deployment's pytest integration tests over UART.

Structure is the Zephyr file with one board instead of two: reusable-get-pr-branch.yml (default_target_ref: main), nasa/fprime-actions/external-repository-setup@devel for build / int, fprime-ci -c ./lib/fprime-samd/ci/sample-configs/samd21g17.yml --add-stage build / --skip-stage build, upgrade-package to a matching fprime-gds pr-xxxx branch.

The pieces it drives live in the community repos and are merged: fprime-community/fprime-samd#62 (samd-ci fprime-ci plugin config + setup-ci action), fprime-community/fprime-samd#63 (assert hooks under the #6326 names), fprime-community/fprime-samd-reference#15 (setup action, integration tests, lib/fprime → nasa devel f28d2da) and fprime-community/fprime-samd-reference#16 (lib/fprime-samd pin).

Rationale

Gives devel a third hardware-in-the-loop reference build, and the first baremetal (no-OS, 16 KiB RAM) one. #6326 and #6285 each broke the SAMD reference without any signal on nasa/fprime; this workflow would have caught both on the PR.

Testing/Review Recommendations

• actionlint reports only the two items the Zephyr workflow also has (apple-ci custom runner label; unquoted ${CI_CONFIG_FILE}).
• The exact fprime-ci build stage runs on an x86 host and the --skip-stage build stage on a Linux aarch64 host with the Curiosity Nano attached: OpenOCD ** Verified OK **, GDS on /dev/samd21-curiosity @ 115200, 3 passed, hardware stage ≈ 40 s. Three such runs are logged in the companion PRs; the final one used the exact pins now on fprime-samd-reference main.
• The apple-ci runner needs, before the integration job can pass: openocd (0.12+ with interface/cmsis-dap.cfg), the udev rule fprime-samd/ci/udev/91-samd21-curiosity.rules (gives /dev/samd21-curiosity), the runner user in dialout/plugdev, and the board on USB. The build job needs nothing beyond setup-ci (it installs the Adafruit SAMD toolchain via arduino-cli).

Future Work

• Second SAMD board (e.g. the Feather M0) would be another include: entry on this file, as the Zephyr file does.

Contributor Checklist

• I have the rights to contribute this change set under the Apache-2.0 license.
• I agree to be bound by the contributor guidelines.

AI Usage (see policy)

Devin (generative AI) wrote the workflow, the community-repo CI plumbing it depends on, and ran the hardware validation, under the direction of @LeStarch who reviewed the plan and merge order.

• This contribution follows the F´ AI development skills (entered through AGENTS.md).

IAMAI

Run findings (resolved)

• Build job: ubuntu-22.04 ships Python 3.10, but fprime-samd's static-tlm-packetizer / static-cmd-dispatcher autocoders need tomllib (3.11+) — the job now runs on ubuntu-24.04 (3.12), matching the floor fprime-samd's own setup-fprime action documents. Green since bb12ead.
• Integration run 1: interface/cmsis-dap.cfg alone attached to the Pico 2 Debug Probe (2e8a:000c, DPv3) rather than the Nano's nEDBG. Fixed in the sample config by ci: pin the OpenOCD probe to the Curiosity Nano's nEDBG (VID:PID 03eb:2175) fprime-community/fprime-samd#64 (cmsis_dap_vid_pid 0x03eb 0x2175), pulled into the reference by Bump lib/fprime-samd to main d4ecc6b (fprime-samd#64: pin the OpenOCD probe to the nEDBG) fprime-community/fprime-samd-reference#17; this workflow reads the reference's main, so no change here.
• Integration run 2: unable to find a matching CMSIS-DAP device — the nEDBG is CMSIS-DAP v1 (HID only) and the runner's from-source raspberrypi/openocd had been built without libhidapi, so it only enumerated v2/bulk probes. Runner fix: rebuild with libhidapi-dev (the fork's internal jimtcl also needs LIBS=-lm, build error missing math flag -lm raspberrypi/openocd#145).
• Integration run 3: flash ** Verified OK **, then the plugin timed out waiting for /dev/samd21-curiosity — fprime-samd/ci/udev/91-samd21-curiosity.rules was not yet installed on the runner. Runner fix: install the rule, udevadm control --reload && udevadm trigger.
• Integration run 4: green — ** Verified OK **, GDS on /dev/samd21-curiosity, 3 passed in 1.59s, CI success!.

Runner prerequisites, as actually verified: openocd ≥ 0.12 with the HID (CMSIS-DAP v1) backend, 91-samd21-curiosity.rules installed, runner user in dialout and plugdev, Nano on USB.

[github-actions]

Coverage report — base devel

Overall (line): 85.81% → 85.93% (+0.12)
Regression threshold: 0.50% (line).

Regressions

Module	Line	Δ	Function	Δ	Branch	Δ
Fw/DataStructures	97.42	-0.54	97.14	+0.00	81.75	-0.91

Modules changed

Module	Line	Δ	Function	Δ	Branch	Δ
Fw/DataStructures	97.42	-0.54	97.14	+0.00	81.75	-0.91
Os/Generic	90.18	-0.10	89.13	+0.00	75.67	+0.38
Os/Generic/Types	92.14	+0.35	92.86	+0.00	74.77	+0.00
Os/Posix	71.03	+0.39	87.50	+0.00	50.89	+0.22
Svc/DpCatalog	89.44	+1.50	98.00	+0.13	82.44	+1.92
Svc/FprimeDeframer	100.00	+1.85	100.00	+0.00	100.00	+4.08
Fw/Types	57.79	+2.30	61.14	+0.45	37.88	+2.60

New modules

Module	Line	Function	Branch
Fw/Prm	0.00	0.00	0.00

Modules without UTs

CFDP/Checksum/GTest, Drv/LinuxGpioDriver, Drv/LinuxI2cDriver, Drv/LinuxSpiDriver, Drv/Ports/DataTypes, Drv/PosixUartDriver, FppTestProject/FppTest/topology/async, FppTestProject/FppTest/topology/components/Comp, FppTestProject/FppTest/topology/components/Framework, FppTestProject/FppTest/topology/components/Receiver, FppTestProject/FppTest/topology/components/Sender, FppTestProject/FppTest/topology/guarded, FppTestProject/FppTest/topology/sync, FppTestProject/FppTest/topology/top_ports, FppTestProject/FppTest/topology/types, Fw/Com, Fw/Comp, Fw/FilePacket/GTest, Fw/Fpy, Fw/Obj, Fw/Port, Fw/Sm, Fw/Test, Fw/Types/GTest, Os/Models, Svc/Ccsds/Types, Svc/Ccsds/Utils, Svc/FatalHandler, Svc/Subtopologies/CdhCore, Svc/Subtopologies/ComCcsds, Svc/Subtopologies/ComCcsdsSdls, Svc/Subtopologies/ComFprime, Svc/Subtopologies/ComLoggerTee, Svc/Subtopologies/DataProducts, Svc/Subtopologies/DpCompression, Svc/Subtopologies/FileHandling, Svc/Subtopologies/FileHandlingCfdp, Svc/Subtopologies/FileHandlingCfdp/FileHandlingCfdpConfig, TestDeploymentsProject/Ref/DpDemo, TestDeploymentsProject/Ref/PingReceiver, TestDeploymentsProject/Ref/RecvBuffApp, TestDeploymentsProject/Ref/SendBuffApp, TestDeploymentsProject/Ref/Top, TestDeploymentsProject/Ref/TypeDemo, cmake/test/data/TestConfigDeployment, cmake/test/data/TestDeployment/TestBuildAutocoder, cmake/test/data/TestDeployment/TestDuplicateDirective, cmake/test/data/TestDeployment/TestHeaderAutocoder, cmake/test/data/TestDeployment/TestLinkDepends, cmake/test/data/TestDeployment/TestRelative, cmake/test/data/test-fprime-library/TestLibrary/TestComponent, cmake/test/data/test-fprime-library2/TestLibrary2/TestComponent