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authorEric Tang <e_l_tang@outlook.com>2016-05-23 20:42:21 -0700
committerJack Humbert <jack.humb@gmail.com>2016-05-23 23:42:21 -0400
commitaaa758f1d3f97dda39879f2b055ad2da9680adfe (patch)
treecb0749cda23c0507dd2b230af3eb0ca81a97b8af /quantum
parentd66aa0abf96b5e887250cf0a7fa5e575f18c5a91 (diff)
Optimize matrix scanning (#343)
Diffstat (limited to 'quantum')
-rw-r--r--quantum/config_common.h125
-rw-r--r--quantum/matrix.c369
-rw-r--r--quantum/template/config.h17
3 files changed, 213 insertions, 298 deletions
diff --git a/quantum/config_common.h b/quantum/config_common.h
index da53fce89b..02f11d979c 100644
--- a/quantum/config_common.h
+++ b/quantum/config_common.h
@@ -1,70 +1,74 @@
#ifndef CONFIG_DEFINITIONS_H
#define CONFIG_DEFINITIONS_H
-#define B0 0x20
-#define B1 0x21
-#define B2 0x22
-#define B3 0x23
-#define B4 0x24
-#define B5 0x25
-#define B6 0x26
-#define B7 0x27
-#define C0 0x30
-#define C1 0x31
-#define C2 0x32
-#define C3 0x33
-#define C4 0x34
-#define C5 0x35
-#define C6 0x36
-#define C7 0x37
-#define D0 0x40
-#define D1 0x41
-#define D2 0x42
-#define D3 0x43
-#define D4 0x44
-#define D5 0x45
-#define D6 0x46
-#define D7 0x47
-#define E0 0x50
-#define E1 0x51
-#define E2 0x52
-#define E3 0x53
-#define E4 0x54
-#define E5 0x55
-#define E6 0x56
-#define E7 0x57
-#define F0 0x60
-#define F1 0x61
-#define F2 0x62
-#define F3 0x63
-#define F4 0x64
-#define F5 0x65
-#define F6 0x66
-#define F7 0x67
-
-#define COL2ROW 0x0
-#define ROW2COL 0x1
+/* diode directions */
+#define COL2ROW 0
+#define ROW2COL 1
+/* I/O pins */
+#define B0 { .input_addr = 3, .bit = 0 }
+#define B1 { .input_addr = 3, .bit = 1 }
+#define B2 { .input_addr = 3, .bit = 2 }
+#define B3 { .input_addr = 3, .bit = 3 }
+#define B4 { .input_addr = 3, .bit = 4 }
+#define B5 { .input_addr = 3, .bit = 5 }
+#define B6 { .input_addr = 3, .bit = 6 }
+#define B7 { .input_addr = 3, .bit = 7 }
+#define C0 { .input_addr = 6, .bit = 0 }
+#define C1 { .input_addr = 6, .bit = 1 }
+#define C2 { .input_addr = 6, .bit = 2 }
+#define C3 { .input_addr = 6, .bit = 3 }
+#define C4 { .input_addr = 6, .bit = 4 }
+#define C5 { .input_addr = 6, .bit = 5 }
+#define C6 { .input_addr = 6, .bit = 6 }
+#define C7 { .input_addr = 6, .bit = 7 }
+#define D0 { .input_addr = 9, .bit = 0 }
+#define D1 { .input_addr = 9, .bit = 1 }
+#define D2 { .input_addr = 9, .bit = 2 }
+#define D3 { .input_addr = 9, .bit = 3 }
+#define D4 { .input_addr = 9, .bit = 4 }
+#define D5 { .input_addr = 9, .bit = 5 }
+#define D6 { .input_addr = 9, .bit = 6 }
+#define D7 { .input_addr = 9, .bit = 7 }
+#define E0 { .input_addr = 0xC, .bit = 0 }
+#define E1 { .input_addr = 0xC, .bit = 1 }
+#define E2 { .input_addr = 0xC, .bit = 2 }
+#define E3 { .input_addr = 0xC, .bit = 3 }
+#define E4 { .input_addr = 0xC, .bit = 4 }
+#define E5 { .input_addr = 0xC, .bit = 5 }
+#define E6 { .input_addr = 0xC, .bit = 6 }
+#define E7 { .input_addr = 0xC, .bit = 7 }
+#define F0 { .input_addr = 0xF, .bit = 0 }
+#define F1 { .input_addr = 0xF, .bit = 1 }
+#define F2 { .input_addr = 0xF, .bit = 2 }
+#define F3 { .input_addr = 0xF, .bit = 3 }
+#define F4 { .input_addr = 0xF, .bit = 4 }
+#define F5 { .input_addr = 0xF, .bit = 5 }
+#define F6 { .input_addr = 0xF, .bit = 6 }
+#define F7 { .input_addr = 0xF, .bit = 7 }
+/* USART configuration */
#ifdef BLUETOOTH_ENABLE
-#ifdef __AVR_ATmega32U4__
- #define SERIAL_UART_BAUD 9600
- #define SERIAL_UART_DATA UDR1
- #define SERIAL_UART_UBRR ((F_CPU/(16UL*SERIAL_UART_BAUD))-1)
- #define SERIAL_UART_RXD_VECT USART1_RX_vect
- #define SERIAL_UART_TXD_READY (UCSR1A&(1<<UDRE1))
- #define SERIAL_UART_INIT() do { \
- UBRR1L = (uint8_t) SERIAL_UART_UBRR; /* baud rate */ \
- UBRR1H = (uint8_t) (SERIAL_UART_UBRR>>8); /* baud rate */ \
- UCSR1B = (1<<TXEN1); /* TX: enable */ \
- UCSR1C = (0<<UPM11) | (0<<UPM10) | /* parity: none(00), even(01), odd(11) */ \
- (0<<UCSZ12) | (1<<UCSZ11) | (1<<UCSZ10); /* data-8bit(011) */ \
- sei(); \
- } while(0)
-#else
-# error "USART configuration is needed."
+# ifdef __AVR_ATmega32U4__
+# define SERIAL_UART_BAUD 9600
+# define SERIAL_UART_DATA UDR1
+# define SERIAL_UART_UBRR (F_CPU / (16UL * SERIAL_UART_BAUD) - 1)
+# define SERIAL_UART_RXD_VECT USART1_RX_vect
+# define SERIAL_UART_TXD_READY (UCSR1A & _BV(UDRE1))
+# define SERIAL_UART_INIT() do { \
+ /* baud rate */ \
+ UBRR1L = SERIAL_UART_UBRR; \
+ /* baud rate */ \
+ UBRR1H = SERIAL_UART_UBRR >> 8; \
+ /* enable TX */ \
+ UCSR1B = _BV(TXEN1); \
+ /* 8-bit data */ \
+ UCSR1C = _BV(UCSZ11) | _BV(UCSZ10); \
+ sei(); \
+ } while(0)
+# else
+# error "USART configuration is needed."
#endif
-
// I'm fairly sure these aren't needed, but oh well - Jack
/*
@@ -113,4 +117,3 @@
#endif
#endif
-
diff --git a/quantum/matrix.c b/quantum/matrix.c
index cab39e117a..22126aa7ae 100644
--- a/quantum/matrix.c
+++ b/quantum/matrix.c
@@ -1,6 +1,6 @@
/*
-Copyright 2012 Jun Wako
-Generated by planckkeyboard.com (2014 Jack Humbert)
+Copyright 2012 Jun Wako
+Copyright 2014 Jack Humbert
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@@ -15,300 +15,211 @@ GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-
-/*
- * scan matrix
- */
#include <stdint.h>
#include <stdbool.h>
#include <avr/io.h>
-#include <util/delay.h>
+#include "wait.h"
#include "print.h"
#include "debug.h"
#include "util.h"
#include "matrix.h"
-#ifndef DEBOUNCE
-# define DEBOUNCE 10
+#ifdef MATRIX_HAS_GHOST
+# error "The universal matrix.c file cannot be used for this keyboard."
#endif
-static uint8_t debouncing = DEBOUNCE;
-/* matrix state(1:on, 0:off) */
-static matrix_row_t matrix[MATRIX_ROWS];
-static matrix_row_t matrix_debouncing[MATRIX_ROWS];
-
-#if DIODE_DIRECTION == ROW2COL
- static matrix_row_t matrix_reversed[MATRIX_COLS];
- static matrix_row_t matrix_reversed_debouncing[MATRIX_COLS];
+#ifndef DEBOUNCING_DELAY
+# define DEBOUNCING_DELAY 5
#endif
-
-#if MATRIX_COLS > 16
- #define SHIFTER 1UL
+static const io_pin_t row_pins[MATRIX_ROWS] = MATRIX_ROW_PINS;
+static const io_pin_t col_pins[MATRIX_COLS] = MATRIX_COL_PINS;
+/* matrix state */
+#if DIODE_DIRECTION == COL2ROW
+static matrix_row_t matrix[MATRIX_ROWS];
+static matrix_row_t debouncing_matrix[MATRIX_ROWS];
#else
- #define SHIFTER 1
+static matrix_col_t matrix[MATRIX_COLS];
+static matrix_col_t debouncing_matrix[MATRIX_COLS];
#endif
+static int8_t debouncing_delay = -1;
+#if DIODE_DIRECTION == COL2ROW
+static void toggle_row(uint8_t row);
static matrix_row_t read_cols(void);
-static void init_cols(void);
-static void unselect_rows(void);
-static void select_row(uint8_t row);
+#else
+static void toggle_col(uint8_t col);
+static matrix_col_t read_rows(void);
+#endif
__attribute__ ((weak))
void matrix_init_quantum(void) {
-
}
__attribute__ ((weak))
void matrix_scan_quantum(void) {
-
}
-inline
-uint8_t matrix_rows(void)
-{
+uint8_t matrix_rows(void) {
return MATRIX_ROWS;
}
-inline
-uint8_t matrix_cols(void)
-{
+uint8_t matrix_cols(void) {
return MATRIX_COLS;
}
-void matrix_init(void)
-{
- // To use PORTF disable JTAG with writing JTD bit twice within four cycles.
- MCUCR |= (1<<JTD);
- MCUCR |= (1<<JTD);
-
-
- // initialize row and col
- unselect_rows();
- init_cols();
-
- // initialize matrix state: all keys off
- for (uint8_t i=0; i < MATRIX_ROWS; i++) {
- matrix[i] = 0;
- matrix_debouncing[i] = 0;
+void matrix_init(void) {
+ /* frees PORTF by setting the JTD bit twice within four cycles */
+ MCUCR |= _BV(JTD);
+ MCUCR |= _BV(JTD);
+ /* initializes the I/O pins */
+#if DIODE_DIRECTION == COL2ROW
+ for (int8_t r = MATRIX_ROWS - 1; r >= 0; --r) {
+ /* DDRxn */
+ _SFR_IO8(row_pins[r].input_addr + 1) |= _BV(row_pins[r].bit);
+ toggle_row(r);
}
-
+ for (int8_t c = MATRIX_COLS - 1; c >= 0; --c) {
+ /* PORTxn */
+ _SFR_IO8(col_pins[c].input_addr + 2) |= _BV(col_pins[c].bit);
+ }
+#else
+ for (int8_t c = MATRIX_COLS - 1; c >= 0; --c) {
+ /* DDRxn */
+ _SFR_IO8(col_pins[c].input_addr + 1) |= _BV(col_pins[c].bit);
+ toggle_col(c);
+ }
+ for (int8_t r = MATRIX_ROWS - 1; r >= 0; --r) {
+ /* PORTxn */
+ _SFR_IO8(row_pins[r].input_addr + 2) |= _BV(row_pins[r].bit);
+ }
+#endif
matrix_init_quantum();
}
-
-uint8_t matrix_scan(void)
-{
-
#if DIODE_DIRECTION == COL2ROW
- for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
- select_row(i);
- _delay_us(30); // without this wait read unstable value.
- matrix_row_t cols = read_cols();
- if (matrix_debouncing[i] != cols) {
- matrix_debouncing[i] = cols;
- if (debouncing) {
- debug("bounce!: "); debug_hex(debouncing); debug("\n");
- }
- debouncing = DEBOUNCE;
+uint8_t matrix_scan(void) {
+ for (int8_t r = MATRIX_ROWS - 1; r >= 0; --r) {
+ toggle_row(r);
+ matrix_row_t state = read_cols();
+ if (debouncing_matrix[r] != state) {
+ debouncing_matrix[r] = state;
+ debouncing_delay = DEBOUNCING_DELAY;
}
- unselect_rows();
+ toggle_row(r);
}
-
- if (debouncing) {
- if (--debouncing) {
- _delay_ms(1);
- } else {
- for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
- matrix[i] = matrix_debouncing[i];
- }
+ if (debouncing_delay >= 0) {
+ dprintf("Debouncing delay remaining: %X\n", debouncing_delay);
+ --debouncing_delay;
+ if (debouncing_delay >= 0) {
+ wait_ms(1);
}
- }
-#else
- for (uint8_t i = 0; i < MATRIX_COLS; i++) {
- select_row(i);
- _delay_us(30); // without this wait read unstable value.
- matrix_row_t rows = read_cols();
- if (matrix_reversed_debouncing[i] != rows) {
- matrix_reversed_debouncing[i] = rows;
- if (debouncing) {
- debug("bounce!: "); debug_hex(debouncing); debug("\n");
+ else {
+ for (int8_t r = MATRIX_ROWS - 1; r >= 0; --r) {
+ matrix[r] = debouncing_matrix[r];
}
- debouncing = DEBOUNCE;
}
- unselect_rows();
}
-
- if (debouncing) {
- if (--debouncing) {
- _delay_ms(1);
- } else {
- for (uint8_t i = 0; i < MATRIX_COLS; i++) {
- matrix_reversed[i] = matrix_reversed_debouncing[i];
- }
- }
- }
- for (uint8_t y = 0; y < MATRIX_ROWS; y++) {
- matrix_row_t row = 0;
- for (uint8_t x = 0; x < MATRIX_COLS; x++) {
- row |= ((matrix_reversed[x] & (1<<y)) >> y) << x;
- }
- matrix[y] = row;
- }
-#endif
-
matrix_scan_quantum();
-
return 1;
}
-bool matrix_is_modified(void)
-{
- if (debouncing) return false;
- return true;
+static void toggle_row(uint8_t row) {
+ /* PINxn */
+ _SFR_IO8(row_pins[row].input_addr) = _BV(row_pins[row].bit);
}
-inline
-bool matrix_is_on(uint8_t row, uint8_t col)
-{
- return (matrix[row] & ((matrix_row_t)1<col));
+static matrix_row_t read_cols(void) {
+ matrix_row_t state = 0;
+ for (int8_t c = MATRIX_COLS - 1; c >= 0; --c) {
+ /* PINxn */
+ if (!(_SFR_IO8(col_pins[c].input_addr) & _BV(col_pins[c].bit))) {
+ state |= (matrix_row_t)1 << c;
+ }
+ }
+ return state;
}
-inline
-matrix_row_t matrix_get_row(uint8_t row)
-{
+matrix_row_t matrix_get_row(uint8_t row) {
return matrix[row];
}
-void matrix_print(void)
-{
- print("\nr/c 0123456789ABCDEF\n");
- for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
- phex(row); print(": ");
- pbin_reverse16(matrix_get_row(row));
- print("\n");
+#else
+uint8_t matrix_scan(void) {
+ for (int8_t c = MATRIX_COLS - 1; c >= 0; --c) {
+ toggle_col(c);
+ matrix_col_t state = read_rows();
+ if (debouncing_matrix[c] != state) {
+ debouncing_matrix[c] = state;
+ debouncing_delay = DEBOUNCING_DELAY;
+ }
+ toggle_col(c);
}
-}
-
-uint8_t matrix_key_count(void)
-{
- uint8_t count = 0;
- for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
- count += bitpop16(matrix[i]);
+ if (debouncing_delay >= 0) {
+ dprintf("Debouncing delay remaining: %X\n", debouncing_delay);
+ --debouncing_delay;
+ if (debouncing_delay >= 0) {
+ wait_ms(1);
+ }
+ else {
+ for (int8_t c = MATRIX_COLS - 1; c >= 0; --c) {
+ matrix[c] = debouncing_matrix[c];
+ }
+ }
}
- return count;
+ matrix_scan_quantum();
+ return 1;
}
-static void init_cols(void)
-{
- int B = 0, C = 0, D = 0, E = 0, F = 0;
+static void toggle_col(uint8_t col) {
+ /* PINxn */
+ _SFR_IO8(col_pins[col].input_addr) = _BV(col_pins[col].bit);
+}
-#if DIODE_DIRECTION == COL2ROW
- for(int x = 0; x < MATRIX_COLS; x++) {
- int col = COLS[x];
-#else
- for(int x = 0; x < MATRIX_ROWS; x++) {
- int col = ROWS[x];
-#endif
- if ((col & 0xF0) == 0x20) {
- B |= (1<<(col & 0x0F));
- } else if ((col & 0xF0) == 0x30) {
- C |= (1<<(col & 0x0F));
- } else if ((col & 0xF0) == 0x40) {
- D |= (1<<(col & 0x0F));
- } else if ((col & 0xF0) == 0x50) {
- E |= (1<<(col & 0x0F));
- } else if ((col & 0xF0) == 0x60) {
- F |= (1<<(col & 0x0F));
- }
+static matrix_col_t read_rows(void) {
+ matrix_col_t state = 0;
+ for (int8_t r = MATRIX_ROWS - 1; r >= 0; --r) {
+ /* PINxn */
+ if (!(_SFR_IO8(row_pins[r].input_addr) & _BV(row_pins[r].bit))) {
+ state |= (matrix_col_t)1 << r;
+ }
}
- DDRB &= ~(B); PORTB |= (B);
- DDRC &= ~(C); PORTC |= (C);
- DDRD &= ~(D); PORTD |= (D);
- DDRE &= ~(E); PORTE |= (E);
- DDRF &= ~(F); PORTF |= (F);
+ return state;
}
-static matrix_row_t read_cols(void)
-{
- matrix_row_t result = 0;
+matrix_row_t matrix_get_row(uint8_t row) {
+ matrix_row_t state = 0;
+ matrix_col_t mask = (matrix_col_t)1 << row;
+ for (int8_t c = MATRIX_COLS - 1; c >= 0; --c) {
+ if (matrix[c] & mask) {
+ state |= (matrix_row_t)1 << c;
+ }
+ }
+ return state;
+}
-#if DIODE_DIRECTION == COL2ROW
- for(int x = 0; x < MATRIX_COLS; x++) {
- int col = COLS[x];
-#else
- for(int x = 0; x < MATRIX_ROWS; x++) {
- int col = ROWS[x];
#endif
- if ((col & 0xF0) == 0x20) {
- result |= (PINB&(1<<(col & 0x0F)) ? 0 : (SHIFTER<<x));
- } else if ((col & 0xF0) == 0x30) {
- result |= (PINC&(1<<(col & 0x0F)) ? 0 : (SHIFTER<<x));
- } else if ((col & 0xF0) == 0x40) {
- result |= (PIND&(1<<(col & 0x0F)) ? 0 : (SHIFTER<<x));
- } else if ((col & 0xF0) == 0x50) {
- result |= (PINE&(1<<(col & 0x0F)) ? 0 : (SHIFTER<<x));
- } else if ((col & 0xF0) == 0x60) {
- result |= (PINF&(1<<(col & 0x0F)) ? 0 : (SHIFTER<<x));
- }
- }
- return result;
+bool matrix_is_modified(void) {
+ if (debouncing_delay >= 0) return false;
+ return true;
}
-static void unselect_rows(void)
-{
- int B = 0, C = 0, D = 0, E = 0, F = 0;
+bool matrix_is_on(uint8_t row, uint8_t col) {
+ return matrix_get_row(row) & (matrix_row_t)1 << col;
+}
-#if DIODE_DIRECTION == COL2ROW
- for(int x = 0; x < MATRIX_ROWS; x++) {
- int row = ROWS[x];
-#else
- for(int x = 0; x < MATRIX_COLS; x++) {
- int row = COLS[x];
-#endif
- if ((row & 0xF0) == 0x20) {
- B |= (1<<(row & 0x0F));
- } else if ((row & 0xF0) == 0x30) {
- C |= (1<<(row & 0x0F));
- } else if ((row & 0xF0) == 0x40) {
- D |= (1<<(row & 0x0F));
- } else if ((row & 0xF0) == 0x50) {
- E |= (1<<(row & 0x0F));
- } else if ((row & 0xF0) == 0x60) {
- F |= (1<<(row & 0x0F));
- }
+void matrix_print(void) {
+ dprintln("Human-readable matrix state:");
+ for (uint8_t r = 0; r < MATRIX_ROWS; r++) {
+ dprintf("State of row %X: %016b\n", r, bitrev16(matrix_get_row(r)));
}
- DDRB &= ~(B); PORTB |= (B);
- DDRC &= ~(C); PORTC |= (C);
- DDRD &= ~(D); PORTD |= (D);
- DDRE &= ~(E); PORTE |= (E);
- DDRF &= ~(F); PORTF |= (F);
}
-static void select_row(uint8_t row)
-{
-
-#if DIODE_DIRECTION == COL2ROW
- int row_pin = ROWS[row];
-#else
- int row_pin = COLS[row];
-#endif
-
- if ((row_pin & 0xF0) == 0x20) {
- DDRB |= (1<<(row_pin & 0x0F));
- PORTB &= ~(1<<(row_pin & 0x0F));
- } else if ((row_pin & 0xF0) == 0x30) {
- DDRC |= (1<<(row_pin & 0x0F));
- PORTC &= ~(1<<(row_pin & 0x0F));
- } else if ((row_pin & 0xF0) == 0x40) {
- DDRD |= (1<<(row_pin & 0x0F));
- PORTD &= ~(1<<(row_pin & 0x0F));
- } else if ((row_pin & 0xF0) == 0x50) {
- DDRE |= (1<<(row_pin & 0x0F));
- PORTE &= ~(1<<(row_pin & 0x0F));
- } else if ((row_pin & 0xF0) == 0x60) {
- DDRF |= (1<<(row_pin & 0x0F));
- PORTF &= ~(1<<(row_pin & 0x0F));
- }
-} \ No newline at end of file
+uint8_t matrix_key_count(void) {
+ uint8_t count = 0;
+ for (int8_t r = MATRIX_ROWS - 1; r >= 0; --r) {
+ count += bitpop16(matrix_get_row(r));
+ }
+ return count;
+}
diff --git a/quantum/template/config.h b/quantum/template/config.h
index e6fb7866c6..cad3e3260a 100644
--- a/quantum/template/config.h
+++ b/quantum/template/config.h
@@ -41,15 +41,16 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
* DIODE_DIRECTION: COL2ROW = COL = Anode (+), ROW = Cathode (-, marked on diode)
* ROW2COL = ROW = Anode (+), COL = Cathode (-, marked on diode)
*
-*/
-#define COLS (int []){ F1, F0, B0 }
-#define ROWS (int []){ D0, D5 }
+*/
+#define MATRIX_ROW_PINS { D0, D5 }
+#define MATRIX_COL_PINS { F1, F0, B0 }
+#define UNUSED_PINS
/* COL2ROW or ROW2COL */
#define DIODE_DIRECTION COL2ROW
/* Debounce reduces chatter (unintended double-presses) - set 0 if debouncing is not needed */
-#define DEBOUNCE 5
+#define DEBOUNCING_DELAY 5
/* define if matrix has ghost (lacks anti-ghosting diodes) */
//#define MATRIX_HAS_GHOST
@@ -62,17 +63,17 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
/* Locking resynchronize hack */
#define LOCKING_RESYNC_ENABLE
-/*
+/*
* Force NKRO
*
- * Force NKRO (nKey Rollover) to be enabled by default, regardless of the saved
+ * Force NKRO (nKey Rollover) to be enabled by default, regardless of the saved
* state in the bootmagic EEPROM settings. (Note that NKRO must be enabled in the
* makefile for this to work.)
*
* If forced on, NKRO can be disabled via magic key (default = LShift+RShift+N)
* until the next keyboard reset.
*
- * NKRO may prevent your keystrokes from being detected in the BIOS, but it is
+ * NKRO may prevent your keystrokes from being detected in the BIOS, but it is
* fully operational during normal computer usage.
*
* For a less heavy-handed approach, enable NKRO via magic key (LShift+RShift+N)
@@ -90,7 +91,7 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
* the keyboard. They are best used in combination with the HID Listen program,
* found here: https://www.pjrc.com/teensy/hid_listen.html
*
- * The options below allow the magic key functionality to be changed. This is
+ * The options below allow the magic key functionality to be changed. This is
* useful if your keyboard/keypad is missing keys and you want magic key support.
*
*/