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+/* Keyboard example with debug channel, for Teensy USB Development Board
+ * http://www.pjrc.com/teensy/usb_keyboard.html
+ * Copyright (c) 2008 PJRC.COM, LLC
+ *
+ * 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.
+ */
+
+#include <avr/io.h>
+#include <avr/pgmspace.h>
+#include <avr/interrupt.h>
+#include <util/delay.h>
+#include "usb_keyboard_debug.h"
+#include "print.h"
+
+#define LED_CONFIG (DDRD |= (1<<6))
+#define LED_ON (PORTD &= ~(1<<6))
+#define LED_OFF (PORTD |= (1<<6))
+#define CPU_PRESCALE(n) (CLKPR = 0x80, CLKPR = (n))
+
+uint8_t number_keys[10]=
+ {KEY_0,KEY_1,KEY_2,KEY_3,KEY_4,KEY_5,KEY_6,KEY_7,KEY_8,KEY_9};
+
+uint16_t idle_count=0;
+
+int main(void)
+{
+ uint8_t b, d, mask, i, reset_idle;
+ uint8_t b_prev=0xFF, d_prev=0xFF;
+
+ // set for 16 MHz clock
+ CPU_PRESCALE(0);
+
+ // Configure all port B and port D pins as inputs with pullup resistors.
+ // See the "Using I/O Pins" page for details.
+ // http://www.pjrc.com/teensy/pins.html
+ DDRD = 0x00;
+ DDRB = 0x00;
+ PORTB = 0xFF;
+ PORTD = 0xFF;
+
+ // Initialize the USB, and then wait for the host to set configuration.
+ // If the Teensy is powered without a PC connected to the USB port,
+ // this will wait forever.
+ usb_init();
+ while (!usb_configured()) /* wait */ ;
+
+ // Wait an extra second for the PC's operating system to load drivers
+ // and do whatever it does to actually be ready for input
+ _delay_ms(1000);
+
+ // Configure timer 0 to generate a timer overflow interrupt every
+ // 256*1024 clock cycles, or approx 61 Hz when using 16 MHz clock
+ // This demonstrates how to use interrupts to implement a simple
+ // inactivity timeout.
+ TCCR0A = 0x00;
+ TCCR0B = 0x05;
+ TIMSK0 = (1<<TOIE0);
+
+ print("Begin keyboard example program\n");
+ print("All Port B or Port D pins are inputs with pullup resistors.\n");
+ print("Any connection to ground on Port B or D pins will result in\n");
+ print("keystrokes sent to the PC (and debug messages here).\n");
+ while (1) {
+ // read all port B and port D pins
+ b = PINB;
+ d = PIND;
+ // check if any pins are low, but were high previously
+ mask = 1;
+ reset_idle = 0;
+ for (i=0; i<8; i++) {
+ if (((b & mask) == 0) && (b_prev & mask) != 0) {
+ usb_keyboard_press(KEY_B, KEY_SHIFT);
+ usb_keyboard_press(number_keys[i], 0);
+ print("Port B, bit ");
+ phex(i);
+ print("\n");
+ reset_idle = 1;
+ }
+ if (((d & mask) == 0) && (d_prev & mask) != 0) {
+ usb_keyboard_press(KEY_D, KEY_SHIFT);
+ usb_keyboard_press(number_keys[i], 0);
+ print("Port D, bit ");
+ phex(i);
+ print("\n");
+ reset_idle = 1;
+ }
+ mask = mask << 1;
+ }
+ // if any keypresses were detected, reset the idle counter
+ if (reset_idle) {
+ // variables shared with interrupt routines must be
+ // accessed carefully so the interrupt routine doesn't
+ // try to use the variable in the middle of our access
+ cli();
+ idle_count = 0;
+ sei();
+ }
+ // now the current pins will be the previous, and
+ // wait a short delay so we're not highly sensitive
+ // to mechanical "bounce".
+ b_prev = b;
+ d_prev = d;
+ _delay_ms(2);
+ }
+}
+
+// This interrupt routine is run approx 61 times per second.
+// A very simple inactivity timeout is implemented, where we
+// will send a space character and print a message to the
+// hid_listen debug message window.
+ISR(TIMER0_OVF_vect)
+{
+ idle_count++;
+ if (idle_count > 61 * 8) {
+ idle_count = 0;
+ print("Timer Event :)\n");
+ usb_keyboard_press(KEY_SPACE, 0);
+ }
+}
+
+