1 /* Copyright (C) 2011 by Jacob Alexander
3 * Permission is hereby granted, free of charge, to any person obtaining a copy
4 * of this software and associated documentation files (the "Software"), to deal
5 * in the Software without restriction, including without limitation the rights
6 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
7 * copies of the Software, and to permit persons to whom the Software is
8 * furnished to do so, subject to the following conditions:
10 * The above copyright notice and this permission notice shall be included in
11 * all copies or substantial portions of the Software.
13 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
14 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
16 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
17 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
18 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23 #include <avr/pgmspace.h>
24 #include <avr/interrupt.h>
25 #include <util/delay.h>
26 //#include "usb_keys.h"
27 #include "scan_loop.h"
28 //#include "layouts.h"
29 //#include "usb_keyboard.h"
32 #include "usb_keyboard_debug.h"
35 #define CPU_PRESCALE(n) (CLKPR = 0x80, CLKPR = (n))
40 // Verified Keypress Defines
41 #define USB_TRANSFER_DIVIDER 10 // 1024 == 1 Send of keypresses per second, 1 == 1 Send of keypresses per ~1 millisecond
44 void errorLED( uint8_t on )
59 // If the matrix is properly set, this function does not need to be changed
60 inline void pinSetup(void)
62 // For each pin, 0=input, 1=output
66 DDRD = 0x40; // LED Setup
71 // Setting pins to either high or pull-up resistor
75 PORTD = 0x40; // LED Enable
82 // Setup with 16 MHz clock
88 // Initialize the USB, and then wait for the host to set configuration.
89 // If the Teensy is powered without a PC connected to the USB port,
90 // this will wait forever.
92 while ( !usb_configured() ) /* wait */ ;
94 // Wait an extra second for the PC's operating system to load drivers
95 // and do whatever it does to actually be ready for input
98 // Setup ISR Timer for flagging a kepress send to USB
99 // Set to 256 * 1024 (8 bit timer with Clock/1024 prescalar) timer
102 TIMSK0 = (1 << TOIE0);
105 // Main Detection Loop
109 // Loop should never get here (indicate error)
112 // HID Debug Error message
113 erro_print("Detection loop error, this is very bad...bug report!");
117 // Timer Interrupt for flagging a send of the sampled key detection data to the USB host
118 uint16_t sendKeypressCounter = 0;
120 ISR( TIMER0_OVF_vect )
122 sendKeypressCounter++;
123 if ( sendKeypressCounter > USB_TRANSFER_DIVIDER ) {
124 sendKeypressCounter = 0;