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  1. Friedrich-Alexander-Universität
  2. Technische Fakultät
  3. Department Informatik
Friedrich-Alexander-Universität Lehrstuhl für Informatik 4 (Systemsoftware)
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                  Aufgabe 2: Unterbrechungen

                  Enumerations | Functions
                  PS2Controller Namespace Reference
                  I/O subsystem

                  PS/2 Controller. More...

                  Enumerations

                  enum  Status {
                    HAS_OUTPUT = 1 << 0 ,
                    INPUT_PENDING = 1 << 1 ,
                    SYSTEM_FLAG = 1 << 2 ,
                    IS_COMMAND = 1 << 3 ,
                    IS_MOUSE = 1 << 5 ,
                    TIMEOUT_ERROR = 1 << 6 ,
                    PARITY_ERROR = 1 << 7
                  }
                   Flags in the PS/2 controller status register. More...
                   
                  enum  KeyboardCommand : uint8_t {
                    KEYBOARD_SET_LED = 0xed ,
                    KEYBOARD_SEND_ECHO = 0xee ,
                    KEYBOARD_SET_SPEED = 0xf3 ,
                    KEYBOARD_ENABLE = 0xf4 ,
                    KEYBOARD_DISABLE = 0xf5 ,
                    KEYBOARD_SET_DEFAULT = 0xf6
                  }
                   Commands to be send to the Keyboard. More...
                   
                  enum  Reply {
                    ACK = 0xfa ,
                    RESEND = 0xfe ,
                    ECHO = 0xee
                  }
                   Replies. More...
                   
                  enum  ControllerCommand {
                    CONTROLLER_GET_COMMAND_BYTE = 0x20 ,
                    CONTROLLER_SET_COMMAND_BYTE = 0x60 ,
                    CONTROLLER_MOUSE_DISABLE = 0xa7 ,
                    CONTROLLER_MOUSE_ENABLE = 0xa8 ,
                    CONTROLLER_KEYBOARD_DISABLE = 0xad ,
                    CONTROLLER_KEYBOARD_ENABLE = 0xae ,
                    CONTROLLER_SEND_TO_MOUSE = 0xd4
                  }
                   Commands for the PS/2 Controller. More...
                   
                  enum  MouseCommand {
                    MOUSE_RESET = 0xff ,
                    MOUSE_DEFAULTS = 0xf6 ,
                    MOUSE_STREAMING_DISABLE = 0xf5 ,
                    MOUSE_STREAMING_ENABLE = 0xf4 ,
                    MOUSE_SAMPLE_RATE = 0xf3 ,
                    MOUSE_ID = 0xf2 ,
                    MOUSE_REQUEST_PACKET = 0xeb ,
                    MOUSE_REQUEST_STATUS = 0xe9 ,
                    MOUSE_RESOLUTION = 0xe8 ,
                    MOUSE_SCALING_2_1 = 0xe7 ,
                    MOUSE_SCALING_1_1 = 0xe6
                  }
                   Commands to be send to the mouse. More...
                   
                  enum  Delay {
                    DELAY_250MS = 0 ,
                    DELAY_500MS = 1 ,
                    DELAY_750MS = 2 ,
                    DELAY_1000MS = 3
                  }
                   Delay before the keyboard starts repeating sending a pressed key. More...
                   
                  enum  Speed {
                    SPEED_30_0CPS = 0x00 ,
                    SPEED_26_7CPS = 0x01 ,
                    SPEED_24_0CPS = 0x02 ,
                    SPEED_21_8CPS = 0x03 ,
                    SPEED_20_7CPS = 0x04 ,
                    SPEED_18_5CPS = 0x05 ,
                    SPEED_17_1CPS = 0x06 ,
                    SPEED_16_0CPS = 0x07 ,
                    SPEED_15_0CPS = 0x08 ,
                    SPEED_13_3CPS = 0x09 ,
                    SPEED_12_0CPS = 0x0a ,
                    SPEED_10_9CPS = 0x0b ,
                    SPEED_10_0CPS = 0x0c ,
                    SPEED_09_2CPS = 0x0d ,
                    SPEED_08_6CPS = 0x0e ,
                    SPEED_08_0CPS = 0x0f ,
                    SPEED_07_5CPS = 0x10 ,
                    SPEED_06_7CPS = 0x11 ,
                    SPEED_06_0CPS = 0x12 ,
                    SPEED_05_5CPS = 0x13 ,
                    SPEED_05_0CPS = 0x14 ,
                    SPEED_04_6CPS = 0x15 ,
                    SPEED_04_3CPS = 0x16 ,
                    SPEED_04_0CPS = 0x17 ,
                    SPEED_03_7CPS = 0x18 ,
                    SPEED_03_3CPS = 0x19 ,
                    SPEED_03_0CPS = 0x1a ,
                    SPEED_02_7CPS = 0x1b ,
                    SPEED_02_5CPS = 0x1c ,
                    SPEED_02_3CPS = 0x1d ,
                    SPEED_02_1CPS = 0x1e ,
                    SPEED_02_0CPS = 0x1f
                  }
                   Repeat Rate of Characters. More...
                   
                  enum  LED {
                    LED_SCROLL_LOCK = 1 << 0 ,
                    LED_NUM_LOCK = 1 << 1 ,
                    LED_CAPS_LOCK = 1 << 2
                  }
                   Keyboard LEDs. More...
                   

                  Functions

                  void init ()
                   Initialization of connected devices. More...
                   
                  bool fetch (Key &pressed)
                   Retrieve the keyboard event. More...
                   
                  bool fetch (Pointer &state)
                   Retrieve the mouse event. More...
                   
                  void setRepeatRate (Speed speed, Delay delay)
                   Configure the repeat rate of the keyboard. More...
                   
                  void setLed (enum LED led, bool on)
                   Enable or disable a keyboard LED. More...
                   
                  void drainBuffer ()
                   Empties the keyboard buffer. More...
                   

                  Detailed Description

                  PS/2 Controller.

                  Initializes the PS/2 devices (Keyboard and optional Mouse), and determines both the scan code and ASCII character of a pressed key from the transmitted make and break codes using the KeyDecoder.

                  Note
                  This controller is also known as Intel 8042 (nowadays integrated in the mainboard) or Keyboard Controller. But to avoid confusion with the actual Keyboard and since we use the PS/2-compatible mode to support the Mouse as well, the name PS/2 Controller was chosen for the sake of simplicity.
                  Since modern PCs sometimes don't have an PS/2 connector, USB keyboards and mice are emulated as PS/2 device with USB Legacy Support.

                  Enumeration Type Documentation

                  enum PS2Controller::Status

                  Flags in the PS/2 controller status register.

                  Enumerator
                  HAS_OUTPUT 

                  Output buffer non-empty?

                  INPUT_PENDING 

                  Is input buffer full?

                  SYSTEM_FLAG 

                  set on soft reset, cleared on power up

                  IS_COMMAND 

                  Is command Byte? (otherwise data)

                  IS_MOUSE 

                  Mouse output has data.

                  TIMEOUT_ERROR 

                  Timeout error.

                  PARITY_ERROR 

                  Parity error.

                  enum PS2Controller::KeyboardCommand : uint8_t

                  Commands to be send to the Keyboard.

                  Enumerator
                  KEYBOARD_SET_LED 

                  Set the LED (according to the following parameter byte)

                  KEYBOARD_SEND_ECHO 

                  Send an echo packet.

                  KEYBOARD_SET_SPEED 

                  Set the repeat rate (according to the following parameter byte)

                  KEYBOARD_ENABLE 

                  Enable Keyboard.

                  KEYBOARD_DISABLE 

                  Disable Keyboard.

                  KEYBOARD_SET_DEFAULT 

                  Load defaults.

                  enum PS2Controller::Reply

                  Replies.

                  Enumerator
                  ACK 

                  Acknowledgement.

                  RESEND 

                  Request to resend (not required to implement)

                  ECHO 

                  Echo answer.

                  enum PS2Controller::ControllerCommand

                  Commands for the PS/2 Controller.

                  These commands are processed by the controller and not send to keyboard/mouse. They have to be written into the command register.

                  Enumerator
                  CONTROLLER_GET_COMMAND_BYTE 

                  Read Command Byte of PS/2 Controller.

                  CONTROLLER_SET_COMMAND_BYTE 

                  Write Command Byte of PS/2 Controller.

                  CONTROLLER_MOUSE_DISABLE 

                  Disable mouse interface.

                  CONTROLLER_MOUSE_ENABLE 

                  Enable mouse interface.

                  CONTROLLER_KEYBOARD_DISABLE 

                  Disable keyboard interface.

                  CONTROLLER_KEYBOARD_ENABLE 

                  Enable keyboard interface.

                  CONTROLLER_SEND_TO_MOUSE 

                  Send parameter to mouse device.

                  enum PS2Controller::MouseCommand

                  Commands to be send to the mouse.

                  See also
                  ps2mouse
                  Enumerator
                  MOUSE_RESET 

                  Reset and perform self-test.

                  MOUSE_DEFAULTS 

                  Reset settings to default.

                  MOUSE_STREAMING_DISABLE 

                  Don't report mouse movements.

                  MOUSE_STREAMING_ENABLE 

                  Send data on mouse movement/button events.

                  MOUSE_SAMPLE_RATE 

                  Set sample rate.

                  MOUSE_ID 

                  Get device ID.

                  MOUSE_REQUEST_PACKET 

                  Get movement data.

                  MOUSE_REQUEST_STATUS 

                  Get status packet (responses with 3 bytes)

                  MOUSE_RESOLUTION 

                  Set resolution (requires parameter)

                  MOUSE_SCALING_2_1 

                  Set scaling 2:1.

                  MOUSE_SCALING_1_1 

                  Set scaling 1:1.

                  enum PS2Controller::Delay

                  Delay before the keyboard starts repeating sending a pressed key.

                  Enumerator
                  DELAY_250MS 

                  Delay of 0.25s.

                  DELAY_500MS 

                  Delay of 0.5s.

                  DELAY_750MS 

                  Delay of 0.75s.

                  DELAY_1000MS 

                  Delay of 1s.

                  enum PS2Controller::Speed

                  Repeat Rate of Characters.

                  See also
                  The PS/2 Keyboard Interface
                  Enumerator
                  SPEED_30_0CPS 

                  30 characters per second

                  SPEED_26_7CPS 

                  26.7 characters per second

                  SPEED_24_0CPS 

                  24 characters per second

                  SPEED_21_8CPS 

                  12.8 characters per second

                  SPEED_20_7CPS 

                  20.7 characters per second

                  SPEED_18_5CPS 

                  18.5 characters per second

                  SPEED_17_1CPS 

                  17.1 characters per second

                  SPEED_16_0CPS 

                  16 characters per second

                  SPEED_15_0CPS 

                  15 characters per second

                  SPEED_13_3CPS 

                  13.3 characters per second

                  SPEED_12_0CPS 

                  12 characters per second

                  SPEED_10_9CPS 

                  10.9 characters per second

                  SPEED_10_0CPS 

                  10 characters per second

                  SPEED_09_2CPS 

                  9.2 characters per second

                  SPEED_08_6CPS 

                  8.6 characters per second

                  SPEED_08_0CPS 

                  8 characters per second

                  SPEED_07_5CPS 

                  7.5 characters per second

                  SPEED_06_7CPS 

                  6.7 characters per second

                  SPEED_06_0CPS 

                  6 characters per second

                  SPEED_05_5CPS 

                  5.5 characters per second

                  SPEED_05_0CPS 

                  5 characters per second

                  SPEED_04_6CPS 

                  4.6 characters per second

                  SPEED_04_3CPS 

                  4.3 characters per second

                  SPEED_04_0CPS 

                  4 characters per second

                  SPEED_03_7CPS 

                  3.7 characters per second

                  SPEED_03_3CPS 

                  3.3 characters per second

                  SPEED_03_0CPS 

                  3 characters per second

                  SPEED_02_7CPS 

                  2.7 characters per second

                  SPEED_02_5CPS 

                  2.5 characters per second

                  SPEED_02_3CPS 

                  2.3 characters per second

                  SPEED_02_1CPS 

                  2.1 characters per second

                  SPEED_02_0CPS 

                  2 characters per second

                  enum PS2Controller::LED

                  Keyboard LEDs.

                  Enumerator
                  LED_SCROLL_LOCK 

                  Scroll Lock.

                  LED_NUM_LOCK 

                  Num Lock.

                  LED_CAPS_LOCK 

                  Caps Lock.

                  Function Documentation

                  void PS2Controller::init ( )

                  Initialization of connected devices.

                  All status LEDs of the keyboard are switched off and the repetition rate is set to maximum speed.

                  bool PS2Controller::fetch ( Key &  pressed)

                  Retrieve the keyboard event.

                  Retrieves make and brake events from the keyboard. If a valid (non special) key was pressed, the scan code is determined using KeyDecoder::decode into a Key object. Events on special keys like Shift, Alt, CapsLock etc. are stored (in KeyDecoder) and applied on subsequent keystrokes, while no valid key is retrieved.

                  Mouse events are ignored.

                  Todo:
                  Adjust method (unless it is already non-blocking)
                  Parameters
                  pressedReference to an object which will contain the pressed Key on success
                  Returns
                  true if a valid key was decoded
                  bool PS2Controller::fetch ( Pointer &  state)

                  Retrieve the mouse event.

                  If a full mouse state was retrieved (all 3 packets have been successfully processed by the MouseDecoder) the new state is retrieved. Keyboard events are not processed.

                  Note
                  fetch(Key&) has to be adjusted to not process (instead of ignore) mouse packets, or events might be lost.
                  Optional:
                  Adjust method
                  Parameters
                  stateReference to an object which will contain the Mouse Pointer state on success
                  Returns
                  true if a valid mouse pointer state was decoded
                  void PS2Controller::setRepeatRate ( Speed  speed,
                  Delay  delay 
                  )

                  Configure the repeat rate of the keyboard.

                  Parameters
                  delayconfigures how long a key must be pressed before the repetition begins.
                  speeddetermines how fast the key codes should follow each other. Valid values are between 0 (30 characters per second) and 31 (2 characters per second).
                  void PS2Controller::setLed ( enum LED  led,
                  bool  on 
                  )

                  Enable or disable a keyboard LED.

                  Parameters
                  ledLED to enable or disable
                  ontrue will enable the specified LED, false disable
                  void PS2Controller::drainBuffer ( )

                  Empties the keyboard buffer.

                  The keyboard may not send any interrupts if the buffer is not empty. To prevent unhandled keystrokes (for example during boot) the buffer should be emptied once right before allowing keyboard interrupts (even if keystrokes might be lost).

                  Todo:
                  Implement method
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