GUI Functions

dev.gui - wire path g - generated from fwMenuGUI.

set_led_color

Set Board LED. Sets a led to a specific color

Requires power zone 10 (LEDs). See Errors.

Set Board LED

Sets the color of one of the seven on-board RGB status LEDs. The new color is applied immediately — no separate refresh/commit call is required.

Arguments

Name	Type	Range	Description
`ledindex`	decU8	`0`–`6`	Which on-board RGB LED to set
`red`	decU8	`0`–`255`	Red channel intensity
`green`	decU8	`0`–`255`	Green channel intensity
`blue`	decU8	`0`–`255`	Blue channel intensity

Returns

success=basic — 1 if the LED was updated, 0 if the arguments could not be parsed or ledindex is out of range.

Examples

Set LED 0 to full green:

0 0 255 0

Set LED 6 to white:

6 255 255 255

Turn LED 3 off:

3 0 0 0

Notes

Indices outside 0–6 are rejected.
Each channel is 8-bit (0–255); higher values are clamped/rejected by the decU8 parser.
To turn an LED off, set all three channels to 0.

Wire command: g\s

Arg	Wire type
ledindex	decU8
red	decU8
green	decU8
blue	decU8
duration	decS32
mode	owLEDManagerLEDMode

Returns: none (Ok/Err only)

dev.gui.set_led_color(ledindex: int, red: int, green: int, blue: int, duration: int, mode: enums.owLEDManagerLEDMode | int) -> Result

ow_status ow_gui_set_led_color(ow_device* dev, int32_t ledindex, int32_t red, int32_t green, int32_t blue, int32_t duration, ow_ow_led_manager_led_mode mode);

dev.gui().set_led_color(ledindex: i32, red: i32, green: i32, blue: i32, duration: i32, mode: owLEDManagerLEDMode) -> Result<(), OwError>

The C and Rust signatures above are also the WASM guest signatures - the device API surface is identical; only the transport differs (ow_open_wasm(&dev) in C, OneWili::open() in Rust).

dev.gui.set_led_color(ledindex, red, green, blue, duration, mode)   # check dev.ok

show_fwi_image

Show FWI Image. Shows an freewili image (fwi) file from the file system.

Show FWI Image

Loads and displays a FreeWili Image (.fwi) file from the on-device filesystem on the 3.5" touchscreen display.

Arguments

Name	Type	Description
`filename`	string	Path to the `.fwi` file to display

Path resolution

If filename begins with \, it is treated as an absolute path on the filesystem (e.g. \images\logo.fwi).
Otherwise, it is resolved relative to \images\ — logo.fwi is loaded as \images\logo.fwi.
Include the .fwi extension explicitly; it is not appended automatically.
The file must already exist on the filesystem.

Returns

success=basic — 1 if the file was found and displayed, 0 if the path could not be resolved, the file does not exist, or the image failed to load.

Examples

Show an image stored in the default \images\ folder:

logo.fwi

Show an image using an absolute path:

\images\subdir\splash.fwi

Notes

.fwi is the FreeWili native image format. Use the FreeWili GUI tools to convert PNG/JPEG assets into .fwi files and copy them to the device's SD card or internal filesystem.
To display an image bundled as a built-in asset (by ID) rather than a file, use Show Asset Image (a) instead.
To clear the screen after viewing, use Reset Display (t).

Wire command: g\l

Arg	Wire type
filename	string

Returns: none (Ok/Err only)

dev.gui.show_fwi_image(filename: str) -> Result

ow_status ow_gui_show_fwi_image(ow_device* dev, const char* filename);

dev.gui().show_fwi_image(filename: &str) -> Result<(), OwError>

The C and Rust signatures above are also the WASM guest signatures - the device API surface is identical; only the transport differs (ow_open_wasm(&dev) in C, OneWili::open() in Rust).

dev.gui.show_fwi_image(filename)   # check dev.ok

clear_display

Reset Display. Clears any GUI menu actions done to the display such as show image or show text

Reset Display

Clears the 3.5" touchscreen of any content drawn by menu commands such as Show FWI Image (l), Show Asset Image (a), or Show Text Display (p), returning the display to its default state.

Arguments

None.

Returns

success=basic — 1 if the display was reset, 0 otherwise.

Examples

Reset the display after viewing an image or text:

Notes

Use this after any of the following to restore the default UI:
- Show FWI Image (l)
- Show Asset Image (a)
- Show Text Display (p)
This command takes no arguments — any input is ignored.
It only affects the display contents; it does not change LED state, button state, or any other peripheral.

Wire command: g\t

Returns: none (Ok/Err only)

dev.gui.clear_display() -> Result

ow_status ow_gui_clear_display(ow_device* dev);

dev.gui().clear_display() -> Result<(), OwError>

The C and Rust signatures above are also the WASM guest signatures - the device API surface is identical; only the transport differs (ow_open_wasm(&dev) in C, OneWili::open() in Rust).

dev.gui.clear_display()   # check dev.ok

show_text

Show Text Display. Show text on the free wili display

Show Text Display

Draws a text overlay on top of the current GUI window on the 3.5" touchscreen display. The underlying GUI is not modified — the text is rendered over it until cleared.

Arguments

Name	Type	Description
`texttodisplay`	string	The text to render as an overlay

Returns

success=basic — 1 if the text was accepted and drawn, 0 if the argument could not be parsed.

Examples

Show a simple greeting:

Hello Wili

Show a status message:

Ready

Show a multi-word string (spaces are part of the text):

Battery OK

Notes

The text is drawn as an overlay above the current GUI window; the GUI underneath is preserved.
Calling Show Text Display again replaces the previous overlay text.
Text longer than the available screen area is truncated to fit — it is not scrolled or wrapped onto additional screens.
To remove the overlay and restore the default display, use Reset Display (t).
To show an image instead of text, use Show FWI Image (l) or Show Asset Image (a).

Wire command: g\p

Arg	Wire type
texttodisplay	string

Returns: none (Ok/Err only)

dev.gui.show_text(texttodisplay: str) -> Result

ow_status ow_gui_show_text(ow_device* dev, const char* texttodisplay);

dev.gui().show_text(texttodisplay: &str) -> Result<(), OwError>

The C and Rust signatures above are also the WASM guest signatures - the device API surface is identical; only the transport differs (ow_open_wasm(&dev) in C, OneWili::open() in Rust).

dev.gui.show_text(texttodisplay)   # check dev.ok

read_all

Read All Buttons. Sets the baud rate for I2C in Hz

Wire command: g\u

Returns: none (Ok/Err only)

dev.gui.read_all() -> Result

ow_status ow_gui_read_all(ow_device* dev);

dev.gui().read_all() -> Result<(), OwError>

The C and Rust signatures above are also the WASM guest signatures - the device API surface is identical; only the transport differs (ow_open_wasm(&dev) in C, OneWili::open() in Rust).

dev.gui.read_all()   # check dev.ok

stream_io

Stream Buttons. Sends GPIO values as a specific rate to host

Wire command: g\o

Arg	Wire type
pin	dec

Returns: none (Ok/Err only)

dev.gui.stream_io(pin: int) -> Result

ow_status ow_gui_stream_io(ow_device* dev, int32_t pin);

dev.gui().stream_io(pin: i32) -> Result<(), OwError>

The C and Rust signatures above are also the WASM guest signatures - the device API surface is identical; only the transport differs (ow_open_wasm(&dev) in C, OneWili::open() in Rust).

dev.gui.stream_io(pin)   # check dev.ok

show_image_asset_by_id

Show Asset Image. Reads the number from the address

Wire command: g\a

Arg	Wire type
image_id	decS32

Returns: none (Ok/Err only)

dev.gui.show_image_asset_by_id(image_id: int) -> Result

ow_status ow_gui_show_image_asset_by_id(ow_device* dev, int32_t image_id);

dev.gui().show_image_asset_by_id(image_id: i32) -> Result<(), OwError>

The C and Rust signatures above are also the WASM guest signatures - the device API surface is identical; only the transport differs (ow_open_wasm(&dev) in C, OneWili::open() in Rust).

dev.gui.show_image_asset_by_id(image_id)   # check dev.ok

screenshot

Screenshot. Saves the display to SD. Args: filename, png/fwi, counter 0/1, timestamp 0/1.

Screenshot

Argument order: filename filetype counter timestamp.

filename: base filename only; DISPLAY adds the extension.
filetype: png for a standard image or fwi for native RGB565 data.
counter: 1 adds the DISPLAY screenshot counter; 0 does not.
timestamp: 1 adds YYYYMMDD-HHMMSS; 0 does not.

Files are written under /screenshots on the SD card. When timestamp and counter are both enabled, the result is filename-YYYYMMDD-HHMMSS-counter.ext. The counter starts at 1, increments only when enabled, and resets when DISPLAY reboots. Directory components are rejected.

Examples:

screen png 0 0 -> screen.png
screen png 0 1 -> screen-YYYYMMDD-HHMMSS.png
screen fwi 1 0 -> screen-1.fwi
screen png 1 1 -> screen-YYYYMMDD-HHMMSS-2.png

Wire command: g\i

Arg	Wire type
filename	string
filetype	owScreenshotFileType
counter	bool
timestamp	bool

Returns: none (Ok/Err only)

dev.gui.screenshot(filename: str, filetype: enums.owScreenshotFileType | int, counter: bool, timestamp: bool) -> Result

ow_status ow_gui_screenshot(ow_device* dev, const char* filename, ow_ow_screenshot_file_type filetype, bool counter, bool timestamp);

dev.gui().screenshot(filename: &str, filetype: owScreenshotFileType, counter: bool, timestamp: bool) -> Result<(), OwError>

The C and Rust signatures above are also the WASM guest signatures - the device API surface is identical; only the transport differs (ow_open_wasm(&dev) in C, OneWili::open() in Rust).

dev.gui.screenshot(filename, filetype, counter, timestamp)   # check dev.ok

simulate_keypress

Simulate Keypress. Injects a button action into the DISPLAY GUI.

Simulate Keypress

Arguments are button presstype. Buttons are gray, yellow, green, blue, red, up, down, left, right, center, ok, cancel, home, or page. Press types are press (normal tap), longpress, pressandstay (held until released), and release.

Examples:

up press
right pressandstay
right release
red longpress

Wire command: g\k

Arg	Wire type
button	owGUIButton
presstype	owButtonPressType

Returns: none (Ok/Err only)

dev.gui.simulate_keypress(button: enums.owGUIButton | int, presstype: enums.owButtonPressType | int) -> Result

ow_status ow_gui_simulate_keypress(ow_device* dev, ow_ow_gui_button button, ow_ow_button_press_type presstype);

dev.gui().simulate_keypress(button: owGUIButton, presstype: owButtonPressType) -> Result<(), OwError>

The C and Rust signatures above are also the WASM guest signatures - the device API surface is identical; only the transport differs (ow_open_wasm(&dev) in C, OneWili::open() in Rust).

dev.gui.simulate_keypress(button, presstype)   # check dev.ok

reinit_lcd_panel

Reinit LCD Panel. Tells DISPLAY to re-initialize its ST7796 LCD panel without rebooting. Arg: mode 0-2.

Reinit LCD Panel

Asks the DISPLAY CPU to re-initialize its ST7796 LCD panel in place, without rebooting either CPU. Use it when the screen goes black with the backlight still lit while the device otherwise responds — the panel has latched a DISPOFF/SLPIN-like state while the GUI kept blitting.

Modes:

0 — send DISPON only (recovers a latched display-off; GRAM and config untouched).
1 — send SLPOUT, wait 120 ms, then DISPON (recovers a latched sleep-in).
2 — full controller re-init, then repaint the current view and restore the backlight.

Start at mode 0 and escalate: the first mode that brings the picture back identifies which state the controller was in. The re-init runs on the DISPLAY's rendering core once any in-flight LCD DMA has finished.

Wire command: g\r

Arg	Wire type
mode	decU8

Returns: none (Ok/Err only)

dev.gui.reinit_lcd_panel(mode: int) -> Result

ow_status ow_gui_reinit_lcd_panel(ow_device* dev, int32_t mode);

dev.gui().reinit_lcd_panel(mode: i32) -> Result<(), OwError>

The C and Rust signatures above are also the WASM guest signatures - the device API surface is identical; only the transport differs (ow_open_wasm(&dev) in C, OneWili::open() in Rust).

dev.gui.reinit_lcd_panel(mode)   # check dev.ok

Events

Spontaneous frames this menu emits (not command responses). Text events arrive as [*<id> ...] frames (Python: Transport.events; C: ow_poll_text_event; Rust: poll_event -> Event::Text); binary events use the binary API below. The on-device rthon and WASM bindings do not receive event streams; menus that expose a polled receive command (for example receive_canfd) are the on-device path.

`button` (text)

Button state report (1 = pressed, per button)

Payload field	Wire type
gray	decU32
yellow	decU32
green	decU32
blue	decU32
red	decU32

Sub-menus

GUI Panels - dev.gui.panels
GUI Controls - dev.gui.controls
GUI Control Properties - dev.gui.control_properties
Dialogs - dev.gui.dialogs

set_led_color​

Set Board LED​

Arguments​

Returns​

Examples​

Notes​

show_fwi_image​

Show FWI Image​

Arguments​

Path resolution​

Returns​

Examples​

Notes​

clear_display​

Reset Display​

Arguments​

Returns​

Examples​

Notes​

show_text​

Show Text Display​

Arguments​

Returns​

Examples​

Notes​

read_all​

stream_io​

show_image_asset_by_id​

screenshot​

Screenshot​

simulate_keypress​

Simulate Keypress​

reinit_lcd_panel​

Reinit LCD Panel​

Events​

button (text)​

Sub-menus​

set_led_color

Set Board LED

Arguments

Returns

Examples

Notes

show_fwi_image

Show FWI Image

Arguments

Path resolution

Returns

Examples

Notes

clear_display

Reset Display

Arguments

Returns

Examples

Notes

show_text

Show Text Display

Arguments

Returns

Examples

Notes

read_all

stream_io

show_image_asset_by_id

screenshot

Screenshot

simulate_keypress

Simulate Keypress

reinit_lcd_panel

Reinit LCD Panel

Events

`button` (text)

Sub-menus