Updating AVR abstraction to be compatible with ARM, nearly ready for ARM files

[kiibohd-controller.git] / Scan / BETKB / scan_loop.c

/* Copyright (C) 2012 by Jacob Alexander
 * 
 * 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.
 */

// ----- Includes -----

// Compiler Includes
#include <Lib/ScanLib.h>

// Project Includes
#include <led.h>
#include <print.h>

// Local Includes
#include "scan_loop.h"



// ----- Defines -----

// Pinout Defines
#define HOLD_PORT PORTD
#define HOLD_DDR   DDRD
#define HOLD_PIN      3


// ----- Macros -----

// Make sure we haven't overflowed the buffer
#define bufferAdd(byte) \
                if ( KeyIndex_BufferUsed < KEYBOARD_BUFFER ) \
                        KeyIndex_Buffer[KeyIndex_BufferUsed++] = byte



// ----- Variables -----

// Buffer used to inform the macro processing module which keys have been detected as pressed
volatile uint8_t KeyIndex_Buffer[KEYBOARD_BUFFER];
volatile uint8_t KeyIndex_BufferUsed;
volatile uint8_t KeyIndex_Add_InputSignal; // Used to pass the (click/input value) to the keyboard for the clicker


// Buffer Signals
volatile uint8_t BufferReadyToClear;



// ----- Function Declarations -----

void processKeyValue( uint8_t keyValue );
void  removeKeyValue( uint8_t keyValue );



// ----- Interrupt Functions -----

// USART Receive Buffer Full Interrupt
ISR(USART1_RX_vect)
{
        cli(); // Disable Interrupts

        uint8_t keyValue = 0x00;
        uint8_t keyState = 0x00;

        // Read the scancode packet from the USART (1st to 8th bits)
        keyValue = UDR1;

        // Read the release/press bit (9th bit) XXX Unnecessary, and wrong it seems, parity bit? or something else?
        keyState = UCSR1B & 0x02;

        // High bit of keyValue, also represents press/release
        keyState = keyValue & 0x80 ? 0x00 : 0x02;

        // Debug
        char tmpStr[6];
        hexToStr( keyValue & 0x7F, tmpStr );

        // Process the scancode
        switch ( keyState )
        {
        case 0x00: // Released
                dPrintStrs( tmpStr, "R  " ); // Debug

                // Remove key from press buffer
                removeKeyValue( keyValue & 0x7F );
                break;

        case 0x02: // Pressed
                dPrintStrs( tmpStr, "P " ); // Debug

                // New key to process
                processKeyValue( keyValue & 0x7F );
                break;
        }

        sei(); // Re-enable Interrupts
}



// ----- Functions -----

// Setup
inline void scan_setup()
{
        // Setup the the USART interface for keyboard data input
        // NOTE: The input data signal needs to be inverted for the Teensy USART to properly work
        
        // Setup baud rate
        // 16 MHz / ( 16 * Baud ) = UBRR
        // Baud <- 0.823284 ms per bit, thus 1000 / 0.823284 = 1214.65004 -> 823.2824
        // Thus baud setting = 823
        uint16_t baud = 823; // Max setting of 4095
        UBRR1H = (uint8_t)(baud >> 8);
        UBRR1L = (uint8_t)baud;

        // Enable the receiver, and RX Complete Interrupt as well as 9 bit data
        UCSR1B = 0x94;

        // The transmitter is only to be enabled when needed
        // Set the pin to be pull-up otherwise (use the lowered voltage inverter in order to sink)
        HOLD_DDR  &= ~(1 << HOLD_PIN);
        HOLD_PORT |=  (1 << HOLD_PIN);

        // Set frame format: 9 data, 1 stop bit, no parity
        // Asynchrounous USART mode
        UCSR1C = 0x06;

        // Initially buffer doesn't need to be cleared (it's empty...)
        BufferReadyToClear = 0;

        // InputSignal is off by default
        KeyIndex_Add_InputSignal = 0x00;

        // Reset the keyboard before scanning, we might be in a wierd state
        scan_resetKeyboard();
}


// Main Detection Loop
// Not needed for the BETKB, this is just a busy loop
inline uint8_t scan_loop()
{
        return 0;
}

void processKeyValue( uint8_t keyValue )
{
        // Interpret scan code
        switch ( keyValue )
        {
        case 0x00: // Break code from input?
                break;
        default:
                // Make sure the key isn't already in the buffer
                for ( uint8_t c = 0; c < KeyIndex_BufferUsed + 1; c++ )
                {
                        // Key isn't in the buffer yet
                        if ( c == KeyIndex_BufferUsed )
                        {
                                bufferAdd( keyValue );

                                // Only send data if enabled
                                if ( KeyIndex_Add_InputSignal )
                                        scan_sendData( KeyIndex_Add_InputSignal );
                                break;
                        }

                        // Key already in the buffer
                        if ( KeyIndex_Buffer[c] == keyValue )
                                break;
                }
                break;
        }
}

void removeKeyValue( uint8_t keyValue )
{
        // Check for the released key, and shift the other keys lower on the buffer
        uint8_t c;
        for ( c = 0; c < KeyIndex_BufferUsed; c++ )
        {
                // Key to release found
                if ( KeyIndex_Buffer[c] == keyValue )
                {
                        // Shift keys from c position
                        for ( uint8_t k = c; k < KeyIndex_BufferUsed - 1; k++ )
                                KeyIndex_Buffer[k] = KeyIndex_Buffer[k + 1];

                        // Decrement Buffer
                        KeyIndex_BufferUsed--;

                        break;
                }
        }

        // Error case (no key to release)
        if ( c == KeyIndex_BufferUsed + 1 )
        {
                errorLED( 1 );
                char tmpStr[6];
                hexToStr( keyValue, tmpStr );
                erro_dPrint( "Could not find key to release: ", tmpStr );
        }
}

// Send data 
uint8_t scan_sendData( uint8_t dataPayload )
{
        // Enable the USART Transmitter
        UCSR1B |=  (1 << 3);

        // Debug
        char tmpStr[6];
        hexToStr( dataPayload, tmpStr );
        info_dPrint( "Sending - ", tmpStr );

        UDR1 = dataPayload;

        // Wait for the payload
        _delay_us( 800 );

        // Disable the USART Transmitter
        UCSR1B &= ~(1 << 3);

        return 0;
}

// Signal KeyIndex_Buffer that it has been properly read
void scan_finishedWithBuffer( uint8_t sentKeys )
{
}

// Signal that the keys have been properly sent over USB
void scan_finishedWithUSBBuffer( uint8_t sentKeys )
{
}

// Reset/Hold keyboard
// NOTE: Does nothing with the BETKB
void scan_lockKeyboard( void )
{
}

// NOTE: Does nothing with the BETKB
void scan_unlockKeyboard( void )
{
}

// Reset Keyboard
void scan_resetKeyboard( void )
{
        // Not a calculated valued...
        _delay_ms( 50 );
}