hid_keycode.hpp File Reference

HID Usage Code (Keyboard Page 0x07) → ASCII char translator (US ANSI layout) More...

#include <cstdint>

Go to the source code of this file.

Namespaces
namespace	m5
	Top level namespace of M5Stack.

Functions
char	m5::unit::tab5_keyboard::hidUsageToChar (const uint8_t keycode, const uint8_t modifier)
	Translate HID Usage Code + modifier to ASCII character (US ANSI layout)
bool	m5::unit::tab5_keyboard::isPrintableHidKey (const uint8_t keycode, const uint8_t modifier)
	Convenience: returns true if hidUsageToChar result is printable ASCII (0x20-0x7E)

Detailed Description

HID Usage Code (Keyboard Page 0x07) → ASCII char translator (US ANSI layout)

Function Documentation

hidUsageToChar()

char m5::unit::tab5_keyboard::hidUsageToChar	(	const uint8_t	keycode,
		const uint8_t	modifier )

Translate HID Usage Code + modifier to ASCII character (US ANSI layout)

Parameters

keycode	HID Usage ID per USB HID spec Keyboard/Keypad Page 0x07
modifier	HID modifier byte. Bit 1 (0x02) = Left Shift, Bit 5 (0x20) = Right Shift. Other bits (Ctrl/Alt/GUI) are ignored.

Return values

!=0	ASCII character (printable or whitespace)
0	Not translatable (modifier-only keys, F-keys, navigation, invalid)

Note

Caps Lock state is NOT tracked here; caller is responsible if needed.

US ANSI layout only. JIS / DE / FR layouts unsupported.

Covers HID Usage IDs 0x04..0x38 (letters, digits, common symbols, whitespace).

isPrintableHidKey()

bool m5::unit::tab5_keyboard::isPrintableHidKey	(	const uint8_t	keycode,
		const uint8_t	modifier )

Convenience: returns true if hidUsageToChar result is printable ASCII (0x20-0x7E)

Parameters

keycode	HID Usage ID
modifier	HID modifier byte

Return values

true	Suitable for direct c display
false	Either not translatable or non-printable control character