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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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                      Erlangen-Nürnberg

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                      91054 Erlangen
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