Solaar/docs/features.md

title	layout
List of HID++ 2.0 features	page

List of HID++ 2.0 features

Feature status

See functions in hidpp20.py and settings_templates.py

Feature	ID	Status	Notes
ROOT	0x0000	✔️	System
FEATURE_SET	0x0001	✔️	System
FEATURE_INFO	0x0002	✔️	System
DEVICE_FW_VERSION	0x0003	✔️	get_firmware, read only
DEVICE_UNIT_ID	0x0004	❌
DEVICE_NAME	0x0005	✔️	get_kind, get_name, read only
DEVICE_GROUPS	0x0006	❌
DEVICE_FRIENDLY_NAME	0x0007	✔️	read only
KEEP_ALIVE	0x0008	❌
RESET	0x0020	❌	aka “Config Change”
CRYPTO_ID	0x0021	❌
TARGET_SOFTWARE	0x0030	❌
WIRELESS_SIGNAL_STRENGTH	0x0080	❌
DFUCONTROL_LEGACY	0x00C0	❌
DFUCONTROL_UNSIGNED	0x00C1	❌
DFUCONTROL_SIGNED	0x00C2	❌
DFU	0x00D0	❌
BATTERY_STATUS	0x1000	✔️	get_battery, read only
BATTERY_VOLTAGE	0x1001	✔️	get_voltage, read only
CHARGING_CONTROL	0x1010	❌
LED_CONTROL	0x1300	❌
GENERIC_TEST	0x1800	❌
DEVICE_RESET	0x1802	❌
OOBSTATE	0x1805	❌
CONFIG_DEVICE_PROPS	0x1806	❌
CHANGE_HOST	0x1814	✔️
HOSTS_INFO	0x1815	➕	get_host_names, partial listing only
BACKLIGHT	0x1981	❌
BACKLIGHT2	0x1982	✔️	_feature_backlight2
BACKLIGHT3	0x1983	❌
PRESENTER_CONTROL	0x1A00	❌
SENSOR_3D	0x1A01	❌
REPROG_CONTROLS	0x1B00	➕	get_keys, only listing
REPROG_CONTROLS_V2	0x1B01	❌
REPROG_CONTROLS_V2_2	0x1B02	❌
REPROG_CONTROLS_V3	0x1B03	❌
REPROG_CONTROLS_V4	0x1B04	➕	get_keys, _feature_reprogrammable_keys
REPORT_HID_USAGE	0x1BC0	❌
PERSISTENT_REMAPPABLE_ACTION	0x1C00	❌
WIRELESS_DEVICE_STATUS	0x1D4B	➕	status reporting from device
REMAINING_PAIRING	0x1DF0	❌
FIRMWARE_PROPERTIES	0x1F1F	❌
ADC_MEASUREMENT	0x1F20	❌
LEFT_RIGHT_SWAP	0x2001	❌
SWAP_BUTTON_CANCEL	0x2005	❌
POINTER_AXIS_ORIENTATION	0x2006	❌
VERTICAL_SCROLLING	0x2100	✔️	get_vertical_scrolling_info, read only
SMART_SHIFT	0x2110	✔️	_feature_smart_shift
HI_RES_SCROLLING	0x2120	✔️	get_hi_res_scrolling_info, _feature_hi_res_scroll
HIRES_WHEEL	0x2121	✔️	get_hires_wheel, _feature_hires_smooth_invert, _feature_hires_smooth_resolution
LOWRES_WHEEL	0x2130	✔️	get_lowres_wheel_status, _feature_lowres_smooth_scroll
THUMB_WHEEL	0x2150	✔️	_feature_thumb_mode, _feature_thumb_invert
MOUSE_POINTER	0x2200	✔️	get_mouse_pointer_info, read only
ADJUSTABLE_DPI	0x2201	✔️	_feature_adjustable_dpi
POINTER_SPEED	0x2205	✔️	get_pointer_speed_info, _feature_pointer_speed
ANGLE_SNAPPING	0x2230	❌
SURFACE_TUNING	0x2240	❌
HYBRID_TRACKING	0x2400	❌
FN_INVERSION	0x40A0	✔️	_feature_fn_swap
NEW_FN_INVERSION	0x40A2	✔️	get_new_fn_inversion, _feature_new_fn_swap
K375S_FN_INVERSION	0x40A3	✔️	_feature_k375s_fn_swap
ENCRYPTION	0x4100	❌
LOCK_KEY_STATE	0x4220	❌
SOLAR_DASHBOARD	0x4301	❌
KEYBOARD_LAYOUT	0x4520	❌	read only
KEYBOARD_DISABLE_KEYS	0x4521	✔️	_feature_disable_keyboard_keys
KEYBOARD_DISABLE_BY_USAGE	0x4522	❌
DUALPLATFORM	0x4530	✔️	_feature_dualplatform, untested
MULTIPLATFORM	0x4531	✔️	_feature_multiplatform
KEYBOARD_LAYOUT_2	0x4540	❌	read only
CROWN	0x4600	✔️
TOUCHPAD_FW_ITEMS	0x6010	❌
TOUCHPAD_SW_ITEMS	0x6011	❌
TOUCHPAD_WIN8_FW_ITEMS	0x6012	❌
TAP_ENABLE	0x6020	❌
TAP_ENABLE_EXTENDED	0x6021	❌
CURSOR_BALLISTIC	0x6030	❌
TOUCHPAD_RESOLUTION	0x6040	❌
TOUCHPAD_RAW_XY	0x6100	❌
TOUCHMOUSE_RAW_POINTS	0x6110	❌
TOUCHMOUSE_6120	0x6120	❌
GESTURE	0x6500	❌
GESTURE_2	0x6501	➕	_feature_gesture2_gestures, _feature_gesture2_params
GKEY	0x8010	➕
MKEYS	0x8020	❌
MR	0x8030	❌
BRIGHTNESS_CONTROL	0x8040	❌
REPORT_RATE	0x8060	✔️
COLOR_LED_EFFECTS	0x8070	❌
RGB_EFFECTS	0X8071	❌
PER_KEY_LIGHTING	0x8080	❌
PER_KEY_LIGHTING_V2	0x8081	❌
MODE_STATUS	0x8090	❌
ONBOARD_PROFILES	0x8100	❌	in progress
MOUSE_BUTTON_SPY	0x8110	❌
LATENCY_MONITORING	0x8111	❌
GAMING_ATTACHMENTS	0x8120	❌
FORCE_FEEDBACK	0x8123	❌
SIDETONE	0x8300	❌
EQUALIZER	0x8310	❌
HEADSET_OUT	0x8320	❌

A “read only” note means the feature is a read-only feature.

Implementing a feature

Features are implemented as settable features in lib/logitech_receiver/settings_templates.py some features also have direct implementation in lib/logitech_receiver/hidpp20.py

In most cases it should suffice to only implement the settable feature interface for each setting in the feature. That will add one or more widgets in the Solaar main window to show and change the setting, will permit storing and restoring changed settings, and will output the feature settings in solaar show.

Adding a setting implementation involves several steps, described here and illustrated by the pointer speed setting implementation.

First add a name, a label, and a description for the setting in the common strings section. The name is used in the persistent settings structure to store and restore changed settings and should be a valid Python identifier. (Some older settings have dashes.) The label is displayed in the Solaar main window and the description is used as a tooltip there. The label and description should be specified as translatable strings.

_POINTER_SPEED = ('pointer_speed',
		_("Sensitivity (Pointer Speed)"),
		_("How fast the pointer moves"))

Next implement an interface for the setting by creating a reader/writer, a validator, and a setting instance for it. Most settings use device features and thus need feature interfaces. Some settings use device register and thus need register interfaces. Only implement a register interface for the setting if you are very brave and you have access to a device that has a register interface for the setting. Register interfaces cannot be auto-discovered and need to be stated in descriptors.py for each device with the register interface.

The reader/writer instance is responsible for reading raw values from the device and writing values to it. There are different classes for feature interfaces and register interfaces. Pointer speed is a feature so the _FeatureRW reader/writer is used. Reader/writers take the register or feature ID and the command numbers for reading and writing, plus other arguments for complex interfaces.

The validator instance is responsible for turning read raw values into Python data and Python data into raw values to be written and validating that the Python data is acceptable for the setting. There are several possible kinds of Python data for setting interfaces, ranging from simple toggles, to ranges, to fixed lists, to dynamic choices, to maps of dynamic choices. Pointer speed is a setting whose values are integers in a range so a _RangeV validator is used. The arguments to this class are the the minimum and maximum values for the value and the byte size of the value on the device. Settings that are toggles or choices work similarly, but their validators have different arguments. Map settings have more complicated validators.

The setting instance keeps everything together and provides control. It takes the strings for the setting, the reader/writer, the validator, and which kinds of devices can have this setting. (This last is no longer used because keyboards with integrated trackpads only report that they are keyboards.)

def _feature_pointer_speed():
    """Pointer Speed feature"""
    # min and max values taken from usb traces of Win software
    validator = _RangeV(0x002e, 0x01ff, 2)
    rw = _FeatureRW(_F.POINTER_SPEED)
    return _Setting(_POINTER_SPEED, rw, validator, device_kind=(_DK.mouse, _DK.trackball))

Settings where the acceptable values are determined from the device need an auxiliary function to receive and decipher the permissible choices. See _feature_adjustable_dpi_choices for an example.

Finally, add an element to _SETTINGS_TABLE with the common strings for the setting, the feature ID (if any), the feature implementation (if any), the register implementation (if any). and the identifier for the setting implementation if different from the setting name. The identifier is used in descriptors.py to say that a device has the register or feature implementation. This table is used to generate the data structures for describing devices in descriptors.py and is also used to auto-discover feature implementations.

_S( _POINTER_SPEED, _F.POINTER_SPEED, _feature_pointer_speed ),

The values to be used need to be determined from documentation of the feature or from reverse-engineering behavior of Logitech software under Windows or MacOS. For more information on implementing feature settings see the comments in lib/logitech_receiver/settings_templates.py.