Arduino¶

OpenSiFli/ArduinoCore-zephyr is a Zephyr-based Arduino core for SF32. It is a useful path for sketches, peripheral experiments, demonstrations, and early prototypes on the SiFli SF32LB52 DevKit LCD.

Beta core

OpenSiFli labels this core BETA. Features, APIs, package contents, loader behavior, and releases may change. Confirm current behavior in the project README and Releases before committing a product to this path.

For the initial IDE installation, board/port selection, bootloader installation, and Blink check, use Getting Started with Arduino. This page is for deciding whether Arduino is a fit and for maintaining an Arduino-based project after that first run.

Where Arduino Fits¶

Choose Arduino when fast iteration and the familiar sketch model matter more than complete access to SF32-specific capabilities. It is a good fit for proof-of-concept work, simple peripheral validation, classroom or demonstration projects, and teams with an existing Arduino codebase.

Move to SiFli-SDK when the product depends on a production firmware baseline, Bluetooth-stack tuning, graphics-heavy applications, low-power optimization, board bring-up, or vendor middleware. Use Zephyr when you need direct control of devicetree, Kconfig, and Zephyr-native application structure.

Table: Arduino platform fit

Choose Arduino for	Prefer another path for
Short sketches and quick peripheral experiments.	A product with broad, validated SF32 feature requirements.
Teams already productive with Arduino IDE or Arduino CLI.	Custom board bring-up or deep control of flash, power, and middleware.
Demonstrations and early feasibility prototypes.	Zephyr-native configuration, drivers, and RTOS structure.

Board Identity¶

The current public package targets the SF32LB52 DevKit LCD. Keep these values in the project record and in issue reports: they determine how the sketch is built, loaded, and mapped to the board.

Table: Arduino board identity

Item	Value
Boards Manager title	SiFli Serial Boards
Arduino platform	`sifli:sf32lb52`
Board	SiFli SF32LB52 DevKit LCD
FQBN	`sifli:sf32lb52:sf32lb52devkitlcd`
Zephyr target	`sf32lb52_devkit_lcd`
Variant	`sf32lb52_devkit_lcd_sf32lb525uc6`
Upload tool	`sftool`
`LED_BUILTIN`	`13`

Selecting a similarly named SiFli or Zephyr board is not interchangeable with this FQBN. The board selection controls the build and upload parameters.

Build and Loader Model¶

ArduinoCore-zephyr combines a sketch-facing Arduino API with a Zephyr loader and board-specific configuration. The two option menus affect startup and linking behavior rather than just compiler flags.

Table: Build and loader choices

Option	Behavior	Engineering implication
`Standard` build mode	Starts the sketch after it is loaded.	Use for normal sketch operation.
`Debug` build mode	Leaves the Zephyr shell waiting for `sketch`.	Useful only when the shell is part of the debug workflow.
`Dynamic` link mode	Packages the sketch for the normal loader-based flow.	Includes the loader in the runtime and memory budget.
`Static` link mode	Uses a statically linked image.	Use for loader-related investigation or when its trade-offs are explicitly understood.

Start with Standard and Dynamic. In Debug mode, an uploaded sketch does not begin until sketch is run from the Zephyr shell; this is a common source of an apparently successful upload with no application behavior.

The loader is a separate board artifact. Burn Bootloader is normally a first-use, update, or recovery operation, not part of every sketch upload. Record the Arduino package version and any loader update together; mismatched assumptions are difficult to diagnose later.

Integration Boundaries¶

Treat the Arduino core as an integration layer rather than a replacement for the underlying Zephyr platform. A sketch can require Zephyr symbols or subsystems that the loader does not expose or enable. Typical symptoms are an undefined Zephyr symbol, a missing subsystem, or memory pressure from dynamic loading and the shell.

Before adding a library or feature to a product prototype, establish all of the following:

The exact package version, FQBN, build mode, and link mode.
The target board revision and its serial-download/recovery procedure.
A tested example for the required peripheral or library.
A measurable RAM and flash budget with the intended loader configuration.
A recovery route using the Arduino loader or SiFli-SDK firmware.

Do not infer library support solely because an Arduino API or a similarly named Zephyr driver exists. Validate the complete sketch, loader, board, and package combination on the target hardware.

Diagnose and Escalate¶

Start with the first-run guide when a board cannot be detected, flashed, or made to run Blink. Once that baseline works, use the following boundary to shorten debugging.

Table: Arduino problem ownership

Symptom after the first-run baseline works	First investigation
Sketch starts only after `sketch`	Confirm that Debug mode was selected intentionally.
Missing Zephyr function or subsystem	Check the Core README and loader exports/configuration.
Memory failure or instability	Measure the sketch budget; account for dynamic loading and the Zephyr shell; evaluate Static only with a recovery plan.
Library compiles but hardware does not work	Confirm board pin assumptions and test against a minimal, board-specific example.
Upload or recovery fails	Re-establish the documented Arduino baseline, then use the board's SiFli-SDK recovery path if needed.

For a useful issue report, include the package version, IDE or CLI version, operating system, FQBN, build mode, link mode, board revision, complete upload output, and serial log.

What SiFli Should Add¶

A versioned compatibility matrix for the Arduino package, Zephyr loader, sftool, and supported board revisions.
A tested Arduino-library and peripheral-support matrix, including known limitations.
Loader update, rollback, and recovery instructions for every supported board.
Minimal, release-tested examples for GPIO, serial I/O, I2C, SPI, display, storage, and low-power behavior.
A support bundle format that captures the package version, FQBN, modes, upload log, and serial log.

Auto-generated content

This page was compiled/drafted without an existing source document. Verify technical claims against SiFli's official documentation before relying on them.