# The MIT License (MIT)
#
# Copyright (c) 2017 Dan Halbert
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
#
"""
`adafruit_hid.keyboard.Keyboard`
====================================================
* Author(s): Scott Shawcroft, Dan Halbert
"""
import time
import usb_hid
from micropython import const
from .keycode import Keycode
[docs]class Keyboard:
"""Send HID keyboard reports."""
# No more than _MAX_KEYPRESSES regular keys may be pressed at once.
_MAX_KEYPRESSES = 6
def __init__(self):
"""Create a Keyboard object that will send USB keyboard HID reports."""
self.hid_keyboard = None
for device in usb_hid.devices:
if device.usage_page == 0x1 and device.usage == 0x06:
self.hid_keyboard = device
break
if not self.hid_keyboard:
raise IOError("Could not find an HID keyboard device.")
# Reuse this bytearray to send keyboard reports.
self.report = bytearray(8)
# report[0] modifiers
# report[1] unused
# report[2:8] regular key presses
# View onto byte 0 in report.
self.report_modifier = memoryview(self.report)[0:1]
# List of regular keys currently pressed.
# View onto bytes 2-7 in report.
self.report_keys = memoryview(self.report)[2:]
# Do a no-op to test if HID device is ready.
# If not, wait a bit and try once more.
try:
self.release_all()
except OSError:
time.sleep(1)
self.release_all()
[docs] def press(self, *keycodes):
"""Send a report indicating that the given keys have been pressed.
:param keycodes: Press these keycodes all at once.
:raises ValueError: if more than six regular keys are pressed.
Keycodes may be modifiers or regular keys.
No more than six regular keys may be pressed simultaneously.
Examples::
from adafruit_hid.keycode import Keycode
# Press ctrl-x.
kbd.press(Keycode.LEFT_CONTROL, Keycode.X)
# Or, more conveniently, use the CONTROL alias for LEFT_CONTROL:
kbd.press(Keycode.CONTROL, Keycode.X)
# Press a, b, c keys all at once.
kbd.press(Keycode.A, Keycode.B, Keycode.C)
"""
for keycode in keycodes:
self._add_keycode_to_report(keycode)
self.hid_keyboard.send_report(self.report)
[docs] def release(self, *keycodes):
"""Send a USB HID report indicating that the given keys have been released.
:param keycodes: Release these keycodes all at once.
If a keycode to be released was not pressed, it is ignored.
Example::
# release SHIFT key
kbd.release(Keycode.SHIFT)
"""
for keycode in keycodes:
self._remove_keycode_from_report(keycode)
self.hid_keyboard.send_report(self.report)
[docs] def release_all(self):
"""Release all pressed keys."""
for i in range(8):
self.report[i] = 0
self.hid_keyboard.send_report(self.report)
[docs] def send(self, *keycodes):
"""Press the given keycodes and then release all pressed keys.
:param keycodes: keycodes to send together
"""
self.press(*keycodes)
self.release_all()
def _add_keycode_to_report(self, keycode):
"""Add a single keycode to the USB HID report."""
modifier = Keycode.modifier_bit(keycode)
if modifier:
# Set bit for this modifier.
self.report_modifier[0] |= modifier
else:
# Don't press twice.
# (I'd like to use 'not in self.report_keys' here, but that's not implemented.)
for i in range(const(self._MAX_KEYPRESSES)):
if self.report_keys[i] == keycode:
# Already pressed.
return
# Put keycode in first empty slot.
for i in range(const(self._MAX_KEYPRESSES)):
if self.report_keys[i] == 0:
self.report_keys[i] = keycode
return
# All slots are filled.
raise ValueError("Trying to press more than six keys at once.")
def _remove_keycode_from_report(self, keycode):
"""Remove a single keycode from the report."""
modifier = Keycode.modifier_bit(keycode)
if modifier:
# Turn off the bit for this modifier.
self.report_modifier[0] &= ~modifier
else:
# Check all the slots, just in case there's a duplicate. (There should not be.)
for i in range(const(self._MAX_KEYPRESSES)):
if self.report_keys[i] == keycode:
self.report_keys[i] = 0