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

/* Copyright (C) 2011-2013 by Joseph Makuch
 * Additions by Jacob Alexander (2013-2014)
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3.0 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
 */

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

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

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

// Local Includes
#include "scan_loop.h"



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

// TODO dfj defines...needs commenting and maybe some cleaning...
#define MAX_PRESS_DELTA_MV 450 // As measured from the Teensy ADC pin
#define THRESHOLD_MV (MAX_PRESS_DELTA_MV >> 1)
//(2560 / (0x3ff/2)) ~= 5
#define MV_PER_ADC 5
#define THRESHOLD (THRESHOLD_MV / MV_PER_ADC)

#define STROBE_SETTLE 1

#define ADHSM 7

// Right justification of ADLAR
#define ADLAR_BITS 0

// full muxmask
#define FULL_MUX_MASK ((1 << MUX0) | (1 << MUX1) | (1 << MUX2) | (1 << MUX3) | (1 << MUX4))

// F0-f7 pins only muxmask.
#define MUX_MASK ((1 << MUX0) | (1 << MUX1) | (1 << MUX2))

// Strobe Masks
#define D_MASK (0xff)
#define E_MASK (0x03)
#define C_MASK (0xff)

// set ADC clock prescale
#define PRESCALE_MASK ((1 << ADPS0) | (1 << ADPS1) | (1 << ADPS2))
#define PRESCALE_SHIFT (ADPS0)
#define PRESCALE 3

// Max number of strobes supported by the hardware
// Strobe lines are detected at startup, extra strobes cause anomalies like phantom keypresses
#define MAX_STROBES 18

// Number of consecutive samples required to pass debounce
#define DEBOUNCE_THRESHOLD 5

// Scans to remain idle after all keys were release before starting averaging
// XXX So this makes the initial keypresses fast,
//      but it's still possible to lose a keypress if you press at the wrong time -HaaTa
#define KEY_IDLE_SCANS 30000

// Total number of muxes/sense lines available
#define MUXES_COUNT 8
#define MUXES_COUNT_XSHIFT 3

// Number of warm-up loops before starting to scan keys
#define WARMUP_LOOPS ( 1024 )
#define WARMUP_STOP (WARMUP_LOOPS - 1)

#define SAMPLE_CONTROL 3

#define KEY_COUNT ((MAX_STROBES) * (MUXES_COUNT))

#define RECOVERY_CONTROL 1
#define RECOVERY_SOURCE  0
#define RECOVERY_SINK    2

#define ON  1
#define OFF 0

// mix in 1/4 of the current average to the running average. -> (@mux_mix = 2)
#define MUX_MIX 2

#define IDLE_COUNT_SHIFT 8

// av = (av << shift) - av + sample; av >>= shift
// e.g. 1 -> (av + sample) / 2 simple average of new and old
//      2 -> (3 * av + sample) / 4 i.e. 3:1 mix of old to new.
//      3 -> (7 * av + sample) / 8 i.e. 7:1 mix of old to new.
#define KEYS_AVERAGES_MIX_SHIFT 3



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

// Select mux
#define SET_FULL_MUX(X) ((ADMUX) = (((ADMUX) & ~(FULL_MUX_MASK)) | ((X) & (FULL_MUX_MASK))))



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

// CLI Functions
void cliFunc_avgDebug   ( char* args );
void cliFunc_echo       ( char* args );
void cliFunc_keyDebug   ( char* args );
void cliFunc_pressDebug ( char* args );
void cliFunc_problemKeys( char* args );
void cliFunc_senseDebug ( char* args );

// Debug Functions
void dumpSenseTable();

// High-level Capsense Functions
void setup_ADC();
void capsense_scan();

// Capsense Sense Functions
void testColumn  ( uint8_t strobe );
void sampleColumn( uint8_t column );

// Low-level Capsense Functions
void strobe_w( uint8_t strobe_num );
void recovery( uint8_t on );



// ----- 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;


// Scan Module command dictionary
char*       scanCLIDictName = "DPH Module Commands";
CLIDictItem scanCLIDict[] = {
        { "echo",        "Example command, echos the arguments.", cliFunc_echo },
        { "avgDebug",    "Enables/Disables averaging results." NL "\t\tDisplays each average, starting from Key 0x00, ignoring 0 valued averages.", cliFunc_avgDebug },
        { "keyDebug",    "Enables/Disables long debug for each keypress." NL "\t\tkeycode - [strobe:mux] : sense val : threshold+delta=total : margin", cliFunc_keyDebug },
        { "pressDebug",  "Enables/Disables short debug for each keypress.", cliFunc_pressDebug },
        { "problemKeys", "Display current list of problem keys,", cliFunc_problemKeys },
        { "senseDebug",  "Prints out the current sense table N times." NL "\t\tsense:max sense:delta", cliFunc_senseDebug },
        { 0, 0, 0 } // Null entry for dictionary end
};

// CLI Control Variables
uint8_t enableAvgDebug   = 0;
uint8_t enableKeyDebug   = 0;
uint8_t enablePressDebug = 1;
uint8_t senseDebugCount  = 3; // In order to get boot-time oddities


// Variables used to calculate the starting sense value (averaging)
uint32_t full_avg = 0;
uint32_t high_avg = 0;
uint32_t  low_avg = 0;

uint8_t  high_count = 0;
uint8_t   low_count = 0;


uint16_t samples[MAX_STROBES][MUXES_COUNT];   // Overall table of cap sense ADC values
uint16_t sampleMax[MAX_STROBES][MUXES_COUNT]; // Records the max seen ADC value

uint8_t  key_activity = 0; // Increments for each detected key per each full scan of the keyboard, it is reset before each full scan
uint16_t key_idle     = 0; // Defines how scans after all keys were released before starting averaging again
uint8_t  key_release  = 0; // Indicates if going from key press state to release state (some keys pressed to no keys pressed)

uint16_t threshold = THRESHOLD;

uint16_t keys_averages_acc[KEY_COUNT];
uint16_t keys_averages    [KEY_COUNT];
uint8_t  keys_debounce    [KEY_COUNT]; // Contains debounce statistics
uint8_t  keys_problem     [KEY_COUNT]; // Marks keys that should be ignored (determined by averaging at startup)

// TODO: change this to 'booting', then count down.
uint16_t boot_count = 0;

uint8_t total_strobes = MAX_STROBES;
uint8_t strobe_map[MAX_STROBES];



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

// Initial setup for cap sense controller
inline void Scan_setup()
{
        // Register Scan CLI dictionary
        CLI_registerDictionary( scanCLIDict, scanCLIDictName );

        // Scan for active strobes
        // NOTE1: On IBM PCBs, each strobe line that is *NOT* used is connected to GND.
        //       This means, the strobe GPIO can be set to Tri-State pull-up to detect which strobe lines are not used.
        // NOTE2: This will *NOT* detect floating strobes.
        // NOTE3: Rev 0.4, the strobe numbers are reversed, so D0 is actually strobe 0 and C7 is strobe 17
        info_msg("Detecting Strobes...");

        DDRC  = 0;
        PORTC = C_MASK;
        DDRD  = 0;
        PORTD = D_MASK;
        DDRE  = 0;
        PORTE = E_MASK;

        // Initially there are 0 strobes
        total_strobes = 0;

        // Iterate over each the strobes
        for ( uint8_t strobe = 0; strobe < MAX_STROBES; strobe++ )
        {
                uint8_t detected = 0;

                // If PIN is high, then strobe is *NOT* connected to GND and may be a strobe
                switch ( strobe )
                {

                // Strobe Mappings
                //              Rev  Rev
                //              0.2  0.4
#ifndef REV0_4_DEBUG // XXX These pins should be reworked, and connect to GND on Rev 0.4
                case 0:  // D0   0   n/c
                case 1:  // D1   1   n/c
#endif
                case 2:  // D2   2   15
                case 3:  // D3   3   14
                case 4:  // D4   4   13
                case 5:  // D5   5   12
                case 6:  // D6   6   11
                case 7:  // D7   7   10
                        detected = PIND & (1 << strobe);
                        break;

                case 8:  // E0   8    9
                case 9:  // E1   9    8
                        detected = PINE & (1 << (strobe - 8));
                        break;

                case 10: // C0  10    7
                case 11: // C1  11    6
                case 12: // C2  12    5
                case 13: // C3  13    4
                case 14: // C4  14    3
                case 15: // C5  15    2
#ifndef REV0_2_DEBUG // XXX If not using the 18 pin connector on Rev 0.2, rework these pins to GND
                case 16: // C6  16    1
                case 17: // C7  17    0
#endif
                        detected = PINC & (1 << (strobe - 10));
                        break;

                default:
                        break;
                }

                // Potential strobe line detected
                if ( detected )
                {
                        strobe_map[total_strobes] = strobe;
                        total_strobes++;
                }
        }

        printInt8( total_strobes );
        print( " strobes found." NL );

        // Setup Pins for Strobing
        DDRC  = C_MASK;
        PORTC = 0;
        DDRD  = D_MASK;
        PORTD = 0;
        DDRE  = E_MASK;
        PORTE = 0 ;

        // Initialize ADC
        setup_ADC();

        // Reset debounce table
        for ( int i = 0; i < KEY_COUNT; ++i )
        {
                keys_debounce[i] = 0;
        }

        // Warm things up a bit before we start collecting data, taking real samples.
        for ( uint8_t i = 0; i < total_strobes; ++i )
        {
                sampleColumn( strobe_map[i] );
        }
}


// Main Detection Loop
// This is where the important stuff happens
inline uint8_t Scan_loop()
{
        capsense_scan();

        // Return non-zero if macro and USB processing should be delayed
        // Macro processing will always run if returning 0
        // USB processing only happens once the USB send timer expires, if it has not, Scan_loop will be called
        //  after the macro processing has been completed
        return 0;
}


// Signal KeyIndex_Buffer that it has been properly read
// NOTE: Only really required for implementing "tricks" in converters for odd protocols
void Scan_finishedWithBuffer( uint8_t sentKeys )
{
        // Convenient place to clear the KeyIndex_Buffer
        KeyIndex_BufferUsed = 0;
        return;
}


// Signal KeyIndex_Buffer that it has been properly read and sent out by the USB module
// NOTE: Only really required for implementing "tricks" in converters for odd protocols
void Scan_finishedWithUSBBuffer( uint8_t sentKeys )
{
        return;
}


inline void capsense_scan()
{
        // Accumulated average used for the next scan
        uint32_t cur_full_avg = 0;
        uint32_t cur_high_avg = 0;

        // Reset average counters
        low_avg = 0;
        low_count = 0;

        high_count = 0;

        // Reset key activity, if there is no key activity, averages will accumulate for sense deltas, otherwise they will be reset
        key_activity = 0;

        // Scan each of the mapped strobes in the matrix
        for ( uint8_t strober = 0; strober < total_strobes; ++strober )
        {
                uint8_t map_strobe = strobe_map[strober];

                // Sample the ADCs for the given column/strobe
                sampleColumn( map_strobe );

                // Only process sense data if warmup is finished
                if ( boot_count >= WARMUP_LOOPS )
                {
                        testColumn( map_strobe );
                }

                uint8_t strobe_line = map_strobe << MUXES_COUNT_XSHIFT;
                for ( int mux = 0; mux < MUXES_COUNT; ++mux )
                {
                        // discard sketchy low bit, and meaningless high bits.
                        uint8_t sample = samples[map_strobe][mux] >> 1;
                        keys_averages_acc[strobe_line + mux] += sample;
                }

                // Accumulate 3 total averages (used for determining starting average during warmup)
                //     full_avg - Average of all sampled lines on the previous scan set
                // cur_full_avg - Average of all sampled lines for this scan set
                //     high_avg - Average of all sampled lines above full_avg on the previous scan set
                // cur_high_avg - Average of all sampled lines above full_avg
                //      low_avg - Average of all sampled lines below or equal to full_avg
                if ( boot_count < WARMUP_LOOPS )
                {
                        for ( uint8_t mux = 0; mux < MUXES_COUNT; ++mux )
                        {
                                uint8_t sample = samples[map_strobe][mux] >> 1;

                                // Sample is high, add it to high avg
                                if ( sample > full_avg )
                                {
                                        high_count++;
                                        cur_high_avg += sample;
                                }
                                // Sample is low, add it to low avg
                                else
                                {
                                        low_count++;
                                        low_avg += sample;
                                }

                                // If sample is higher than previous high_avg, then mark as "problem key"
                                // XXX Giving a bit more margin to pass (high_avg vs. high_avg + high_avg - full_avg) -HaaTa
                                keys_problem[strobe_line + mux] = sample > high_avg + (high_avg - full_avg) ? sample : 0;

                                // Prepare for next average
                                cur_full_avg += sample;
                        }
                }
        } // for strober

        // Update total sense average (only during warm-up)
        if ( boot_count < WARMUP_LOOPS )
        {
                full_avg = cur_full_avg / (total_strobes * MUXES_COUNT);
                high_avg = cur_high_avg / high_count;
                low_avg /= low_count;

                // Update the base average value using the low_avg (best chance of not ignoring a keypress)
                for ( int i = 0; i < KEY_COUNT; ++i )
                {
                        keys_averages[i] = low_avg;
                        keys_averages_acc[i] = low_avg;
                }
        }

        // Warm up voltage references
        if ( boot_count < WARMUP_LOOPS )
        {
                boot_count++;

                switch ( boot_count )
                {
                // First loop
                case 1:
                        // Show msg at first iteration only
                        info_msg("Warming up the voltage references");
                        break;
                // Middle iterations
                case 300:
                case 600:
                case 900:
                case 1200:
                        print(".");
                        break;
                // Last loop
                case WARMUP_STOP:
                        print( NL );
                        info_msg("Warmup finished using ");
                        printInt16( WARMUP_LOOPS );
                        print(" iterations" NL );

                        // Display the final calculated averages of all the sensed strobes
                        info_msg("Full average (");
                        printInt8( total_strobes * MUXES_COUNT );
                        print("): ");
                        printHex( full_avg );

                        print("  High average (");
                        printInt8( high_count );
                        print("): ");
                        printHex( high_avg );

                        print("  Low average (");
                        printInt8( low_count );
                        print("): ");
                        printHex( low_avg );

                        print("  Rejection threshold: ");
                        printHex( high_avg + (high_avg - full_avg) );
                        print( NL );

                        // Display problem keys, and the sense value at the time
                        for ( uint8_t key = 0; key < KEY_COUNT; key++ )
                        {
                                if ( keys_problem[key] )
                                {
                                        warn_msg("Problem key detected: ");
                                        printHex( key );
                                        print(" (");
                                        printHex( keys_problem[key] );
                                        print(")" NL );
                                }
                        }

                        info_print("If problem keys were detected, and were being held down, they will be reset as soon as let go");
                        break;
                }
        }
        else
        {
                // No keypress, accumulate averages
                if( !key_activity )
                {
                        // Only start averaging once the idle counter has counted down to 0
                        if ( key_idle == 0 )
                        {
                                // Average Debugging
                                if ( enableAvgDebug )
                                {
                                        print("\033[1mAvg\033[0m: ");
                                }

                                // aggregate
                                for ( uint8_t i = 0; i < KEY_COUNT; ++i )
                                {
                                        uint16_t acc = keys_averages_acc[i];
                                        //uint16_t acc = keys_averages_acc[i] >> IDLE_COUNT_SHIFT; // XXX This fixes things... -HaaTa
                                        uint32_t av = keys_averages[i];

                                        av = (av << KEYS_AVERAGES_MIX_SHIFT) - av + acc;
                                        av >>= KEYS_AVERAGES_MIX_SHIFT;

                                        keys_averages[i] = av;
                                        keys_averages_acc[i] = 0;

                                        // Average Debugging
                                        if ( enableAvgDebug && av > 0 )
                                        {
                                                printHex( av );
                                                print(" ");
                                        }
                                }

                                // Average Debugging
                                if ( enableAvgDebug )
                                {
                                        print( NL );
                                }

                                // No key presses detected, set key_release indicator
                                key_release = 1;
                        }
                        // Otherwise decrement the idle counter
                        else
                        {
                                key_idle--;
                        }
                }
                // Keypresses, reset accumulators
                else if ( key_release )
                {
                        for ( uint8_t c = 0; c < KEY_COUNT; ++c ) { keys_averages_acc[c] = 0; }

                        key_release = 0;
                }

                // If the debugging sense table is non-zero, display
                if ( senseDebugCount > 0 )
                {
                        senseDebugCount--;
                        print( NL );
                        dumpSenseTable();
                }
        }
}


void setup_ADC()
{
        // disable adc digital pins.
        DIDR1 |= (1 << AIN0D) | (1<<AIN1D); // set disable on pins 1,0.
        DDRF = 0x0;
        PORTF = 0x0;
        uint8_t mux = 0 & 0x1f; // 0 == first. // 0x1e = 1.1V ref.

        // 0 = external aref 1,1 = 2.56V internal ref
        uint8_t aref = ((1 << REFS1) | (1 << REFS0)) & ((1 << REFS1) | (1 << REFS0));
        uint8_t adate = (1 << ADATE) & (1 << ADATE); // trigger enable
        uint8_t trig = 0 & ((1 << ADTS0) | (1 << ADTS1) | (1 << ADTS2)); // 0 = free running
        // ps2, ps1 := /64 ( 2^6 ) ps2 := /16 (2^4), ps1 := 4, ps0 :=2, PS1,PS0 := 8 (2^8)
        uint8_t prescale = ( ((PRESCALE) << PRESCALE_SHIFT) & PRESCALE_MASK ); // 001 == 2^1 == 2
        uint8_t hispeed = (1 << ADHSM);
        uint8_t en_mux = (1 << ACME);

        ADCSRA = (1 << ADEN) | prescale; // ADC enable

        // select ref.
        //ADMUX |= ((1 << REFS1) | (1 << REFS0)); // 2.56 V internal.
        //ADMUX |= ((1 << REFS0) ); // Vcc with external cap.
        //ADMUX &= ~((1 << REFS1) | (1 << REFS0)); // 0,0 : aref.
        ADMUX = aref | mux | ADLAR_BITS;

        // set free-running
        ADCSRA |= adate; // trigger enable
        ADCSRB  = en_mux | hispeed | trig | (ADCSRB & ~((1 << ADTS0) | (1 << ADTS1) | (1 << ADTS2))); // trigger select free running

        ADCSRA |= (1 << ADEN); // ADC enable
        ADCSRA |= (1 << ADSC); // start conversions q
}


void recovery( uint8_t on )
{
        DDRB  |=  (1 << RECOVERY_CONTROL);
        PORTB &= ~(1 << RECOVERY_SINK);   // SINK always zero
        DDRB  &= ~(1 << RECOVERY_SOURCE); // SOURCE high imp

        if ( on )
        {
                // set strobes to sink to gnd.
                DDRC |= C_MASK;
                DDRD |= D_MASK;
                DDRE |= E_MASK;

                PORTC &= ~C_MASK;
                PORTD &= ~D_MASK;
                PORTE &= ~E_MASK;

                DDRB  |= (1 << RECOVERY_SINK);   // SINK pull
                PORTB |= (1 << RECOVERY_CONTROL);
                PORTB |= (1 << RECOVERY_SOURCE); // SOURCE high
                DDRB  |= (1 << RECOVERY_SOURCE);
        }
        else
        {
                PORTB &= ~(1 << RECOVERY_CONTROL);
                DDRB  &= ~(1 << RECOVERY_SOURCE);
                PORTB &= ~(1 << RECOVERY_SOURCE); // SOURCE low
                DDRB  &= ~(1 << RECOVERY_SINK);   // SINK high-imp
        }
}


void hold_sample( uint8_t on )
{
        if ( !on )
        {
                PORTB |= (1 << SAMPLE_CONTROL);
                DDRB  |= (1 << SAMPLE_CONTROL);
        }
        else
        {
                DDRB  |=  (1 << SAMPLE_CONTROL);
                PORTB &= ~(1 << SAMPLE_CONTROL);
        }
}


void strobe_w( uint8_t strobe_num )
{
        PORTC &= ~(C_MASK);
        PORTD &= ~(D_MASK);
        PORTE &= ~(E_MASK);

        // Strobe table
        // Not all strobes are used depending on which are detected
        switch ( strobe_num )
        {

        case 0:  PORTD |= (1 << 0); break;
        case 1:  PORTD |= (1 << 1); break;
        case 2:  PORTD |= (1 << 2); break;
        case 3:  PORTD |= (1 << 3); break;
        case 4:  PORTD |= (1 << 4); break;
        case 5:  PORTD |= (1 << 5); break;
        case 6:  PORTD |= (1 << 6); break;
        case 7:  PORTD |= (1 << 7); break;

        case 8:  PORTE |= (1 << 0); break;
        case 9:  PORTE |= (1 << 1); break;

        case 10: PORTC |= (1 << 0); break;
        case 11: PORTC |= (1 << 1); break;
        case 12: PORTC |= (1 << 2); break;
        case 13: PORTC |= (1 << 3); break;
        case 14: PORTC |= (1 << 4); break;
        case 15: PORTC |= (1 << 5); break;
        case 16: PORTC |= (1 << 6); break;
        case 17: PORTC |= (1 << 7); break;

        default:
                break;
        }
}


inline uint16_t getADC(void)
{
        ADCSRA |= (1 << ADIF); // clear int flag by writing 1.

        //wait for last read to complete.
        while ( !( ADCSRA & (1 << ADIF) ) );

        return ADC; // return sample
}


void sampleColumn( uint8_t column )
{
        // ensure all probe lines are driven low, and chill for recovery delay.
        ADCSRA |= (1 << ADEN) | (1 << ADSC); // enable and start conversions

        PORTC &= ~C_MASK;
        PORTD &= ~D_MASK;
        PORTE &= ~E_MASK;

        PORTF = 0;
        DDRF  = 0;

        recovery( OFF );
        strobe_w( column );

        hold_sample( OFF );
        SET_FULL_MUX( 0 );

        // Allow strobes to settle
        for ( uint8_t i = 0; i < STROBE_SETTLE; ++i ) { getADC(); }

        hold_sample( ON );

        uint8_t mux = 0;
        SET_FULL_MUX( mux );
        getADC(); // throw away; unknown mux.
        do {
                SET_FULL_MUX( mux + 1 ); // our *next* sample will use this

                // retrieve current read.
                uint16_t readVal = getADC();
                samples[column][mux] = readVal;

                // Update max sense sample table
                if ( readVal > sampleMax[column][mux] )
                {
                        sampleMax[column][mux] = readVal;
                }

                mux++;

        } while ( mux < 8 );

        hold_sample( OFF );
        recovery( ON );

        // turn off adc.
        ADCSRA &= ~(1 << ADEN);

        // pull all columns' strobe-lines low.
        DDRC |= C_MASK;
        DDRD |= D_MASK;
        DDRE |= E_MASK;

        PORTC &= ~C_MASK;
        PORTD &= ~D_MASK;
        PORTE &= ~E_MASK;
}


void testColumn( uint8_t strobe )
{
        uint16_t db_delta = 0;
        uint8_t  db_sample = 0;
        uint16_t db_threshold = 0;

        uint8_t column = 0;
        uint8_t bit = 1;

        for ( uint8_t mux = 0; mux < MUXES_COUNT; ++mux )
        {
                uint16_t delta = keys_averages[(strobe << MUXES_COUNT_XSHIFT) + mux];

                uint8_t key = (strobe << MUXES_COUNT_XSHIFT) + mux;

                // Check if this is a bad key (e.g. test point, or non-existent key)
                if ( keys_problem[key] )
                {
                        // If the sample value of the problem key goes below full_avg (overall initial average)
                        //  re-enable the key
                        if ( (db_sample = samples[strobe][mux] >> 1) < full_avg )
                        {
                                info_msg("Re-enabling problem key: ");
                                printHex( key );
                                print( NL );

                                keys_problem[key] = 0;
                        }

                        // Do not waste any more cycles processing, regardless, a keypress cannot be detected
                        continue;
                }

                // Keypress detected
                //  db_sample (uint8_t), discard meaningless high bit, and garbage low bit
                if ( (db_sample = samples[strobe][mux] >> 1) > (db_threshold = threshold) + (db_delta = delta) )
                {
                        column |= bit;
                        key_activity++; // No longer idle, stop averaging ADC data
                        key_idle = KEY_IDLE_SCANS; // Reset idle count-down

                        // Only register keypresses once the warmup is complete, or not enough debounce info
                        if ( keys_debounce[key] <= DEBOUNCE_THRESHOLD )
                        {
                                // Add to the Macro processing buffer if debounce criteria met
                                // Automatically handles converting to a USB code and sending off to the PC
                                if ( keys_debounce[key] == DEBOUNCE_THRESHOLD )
                                {
                                        // Debug message, pressDebug CLI
                                        if ( enablePressDebug )
                                        {
                                                print("0x");
                                                printHex_op( key, 2 );
                                                print(" ");
                                        }

                                        // Only add the key to the buffer once
                                        // NOTE: Buffer can easily handle multiple adds, just more efficient
                                        //        and nicer debug messages :P
                                        //Macro_bufferAdd( key );
                                }

                                keys_debounce[key]++;

                        }

                        // Long form key debugging
                        if ( enableKeyDebug )
                        {
                                // Debug message
                                // <key> [<strobe>:<mux>] : <sense val> : <delta + threshold> : <margin>
                                dbug_msg("0x");
                                printHex_op( key, 2 );
                                print(" [");
                                printInt8( strobe );
                                print(":");
                                printInt8( mux );
                                print("] : ");
                                printHex( db_sample ); // Sense
                                print(" : ");
                                printHex( db_threshold );
                                print("+");
                                printHex( db_delta );
                                print("=");
                                printHex( db_threshold + db_delta ); // Sense compare
                                print(" : ");
                                printHex( db_sample - ( db_threshold + db_delta ) ); // Margin
                                print( NL );
                        }
                }
                // Clear debounce entry if no keypress detected
                else
                {
                        // If the key was previously pressed, remove from the buffer
                        for ( uint8_t c = 0; c < KeyIndex_BufferUsed; c++ )
                        {
                                // Key to release found
                                if ( KeyIndex_Buffer[c] == key )
                                {
                                        // 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;
                                }
                        }


                        // Clear debounce entry
                        keys_debounce[key] = 0;
                }

                bit <<= 1;
        }
}


void dumpSenseTable()
{
        // Initial table alignment, with base threshold used for every key
        print("\033[1m");
        printHex( threshold );
        print("\033[0m       ");

        // Print out headers first
        for ( uint8_t mux = 0; mux < MUXES_COUNT; ++mux )
        {
                print("  Mux \033[1m");
                printInt8( mux );
                print("\033[0m  ");
        }

        print( NL );

        // Display the full strobe/sense table
        for ( uint8_t strober = 0; strober < total_strobes; ++strober )
        {
                uint8_t strobe = strobe_map[strober];

                // Display the strobe
                print("Strobe \033[1m");
                printHex( strobe );
                print("\033[0m ");

                // For each mux, display sense:threshold:delta
                for ( uint8_t mux = 0; mux < MUXES_COUNT; ++mux )
                {
                        uint8_t delta = keys_averages[(strobe << MUXES_COUNT_XSHIFT) + mux];
                        uint8_t sample = samples[strobe][mux] >> 1;
                        uint8_t max = sampleMax[strobe][mux] >> 1;

                        // Indicate if the key is being pressed by displaying green
                        if ( sample > delta + threshold )
                        {
                                print("\033[1;32m");
                        }

                        printHex_op( sample, 2 );
                        print(":");
                        printHex_op( max, 2 );
                        print(":");
                        printHex_op( delta, 2 );
                        print("\033[0m ");
                }

                // New line for each strobe
                print( NL );
        }
}


// ----- CLI Command Functions -----

// XXX Just an example command showing how to parse arguments (more complex than generally needed)
void cliFunc_echo( char* args )
{
        char* curArgs;
        char* arg1Ptr;
        char* arg2Ptr = args;

        // Parse args until a \0 is found
        while ( 1 )
        {
                print( NL ); // No \r\n by default after the command is entered

                curArgs = arg2Ptr; // Use the previous 2nd arg pointer to separate the next arg from the list
                CLI_argumentIsolation( curArgs, &arg1Ptr, &arg2Ptr );

                // Stop processing args if no more are found
                if ( *arg1Ptr == '\0' )
                        break;

                // Print out the arg
                dPrint( arg1Ptr );
        }
}

void cliFunc_avgDebug( char* args )
{
        print( NL );

        // Args ignored, just toggling
        if ( enableAvgDebug )
        {
                info_print("Cap Sense averaging debug disabled.");
                enableAvgDebug = 0;
        }
        else
        {
                info_print("Cap Sense averaging debug enabled.");
                enableAvgDebug = 1;
        }
}

void cliFunc_keyDebug( char* args )
{
        print( NL );

        // Args ignored, just toggling
        if ( enableKeyDebug )
        {
                info_print("Cap Sense key long debug disabled - pre debounce.");
                enableKeyDebug = 0;
        }
        else
        {
                info_print("Cap Sense key long debug enabled - pre debounce.");
                enableKeyDebug = 1;
        }
}

void cliFunc_pressDebug( char* args )
{
        print( NL );

        // Args ignored, just toggling
        if ( enablePressDebug )
        {
                info_print("Cap Sense key debug disabled - post debounce.");
                enablePressDebug = 0;
        }
        else
        {
                info_print("Cap Sense key debug enabled - post debounce.");
                enablePressDebug = 1;
        }
}

void cliFunc_problemKeys( char* args )
{
        print( NL );

        uint8_t count = 0;

        // Args ignored, just displaying
        // Display problem keys, and the sense value at the time
        for ( uint8_t key = 0; key < KEY_COUNT; key++ )
        {
                if ( keys_problem[key] )
                {
                        if ( count++ == 0 )
                        {
                                warn_msg("Problem keys: ");
                        }
                        printHex( key );
                        print(" (");
                        printHex( keys_problem[key] );
                        print(")   "  );
                }
        }
}

void cliFunc_senseDebug( char* args )
{
        // Parse code from argument
        //  NOTE: Only first argument is used
        char* arg1Ptr;
        char* arg2Ptr;
        CLI_argumentIsolation( args, &arg1Ptr, &arg2Ptr );

        // Default to a single print
        senseDebugCount = 1;

        // If there was an argument, use that instead
        if ( *arg1Ptr != '\0' )
        {
                senseDebugCount = decToInt( arg1Ptr );
        }
}