1 /* Copyright (C) 2011-2013 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
22 // ----- Includes -----
25 #include <Lib/MainLib.h>
29 #include <scan_loop.h>
37 // ----- Defines -----
39 // Verified Keypress Defines
40 #define USB_TRANSFER_DIVIDER 10 // 1024 == 1 Send of keypresses per second, 1 == 1 Send of keypresses per ~1 millisecond
45 #if defined(_at90usb162_) || defined(_atmega32u4_) || defined(_at90usb646_) || defined(_at90usb1286_)
46 #define CPU_PRESCALE(n) (CLKPR = 0x80, CLKPR = (n))
51 // ----- Variables -----
53 // Timer Interrupt for flagging a send of the sampled key detection data to the USB host
54 uint16_t sendKeypressCounter = 0;
56 // Flag generated by the timer interrupt
57 volatile uint8_t sendKeypresses = 0;
61 // ----- Functions -----
63 // Initial Pin Setup, make sure they are sane
64 inline void pinSetup(void)
68 #if defined(_at90usb162_) || defined(_atmega32u4_) || defined(_at90usb646_) || defined(_at90usb1286_)
70 // For each pin, 0=input, 1=output
71 #if defined(__AVR_AT90USB1286__)
81 // Setting pins to either high or pull-up resistor
82 #if defined(__AVR_AT90USB1286__)
92 #elif defined(_mk20dx128_)
93 // TODO - Should be cleared, but not that necessary due to the pin layout
98 inline void usbTimerSetup(void)
101 #if defined(_at90usb162_) || defined(_atmega32u4_) || defined(_at90usb646_) || defined(_at90usb1286_)
103 // Setup with 16 MHz clock
106 // Setup ISR Timer for flagging a kepress send to USB
107 // Set to 256 * 1024 (8 bit timer with Clock/1024 prescalar) timer
110 TIMSK0 = (1 << TOIE0);
113 #elif defined(_mk20dx128_)
114 // 48 MHz clock by default
116 // System Clock Gating Register Disable
117 SIM_SCGC6 |= SIM_SCGC6_PIT;
122 // Setup ISR Timer for flagging a kepress send to USB
123 // 1 ms / (1 / 48 MHz) - 1 = 47999 cycles -> 0xBB7F
124 PIT_LDVAL0 = 0x0000BB7F;
125 PIT_TCTRL0 = 0x3; // Enable Timer 0 interrupts, and Enable Timer 0
127 // Insert the required vector for Timer 0
128 NVIC_ENABLE_IRQ( IRQ_PIT_CH0 );
142 // Setup ISR Timer for flagging a kepress send to USB
145 // Main Detection Loop
146 uint8_t ledTimer = F_CPU / 1000000; // Enable LED for a short time
149 // Setup the scanning module
154 // Acquire Key Indices
155 // Loop continuously until scan_loop returns 0
157 while ( scan_loop() );
160 // Run Macros over Key Indices and convert to USB Keys
163 // Send keypresses over USB if the ISR has signalled that it's time
164 if ( !sendKeypresses )
170 // Clear sendKeypresses Flag
173 // Indicate Error, if valid
174 errorLED( ledTimer );
180 // Loop should never get here (indicate error)
183 // HID Debug Error message
184 erro_print("Detection loop error, this is very bad...bug report!");
189 // ----- Interrupts -----
191 // USB Keyboard Data Send Counter Interrupt
192 #if defined(_at90usb162_) || defined(_atmega32u4_) || defined(_at90usb646_) || defined(_at90usb1286_) // AVR
193 ISR( TIMER0_OVF_vect )
194 #elif defined(_mk20dx128_) // ARM
198 sendKeypressCounter++;
199 if ( sendKeypressCounter > USB_TRANSFER_DIVIDER ) {
200 sendKeypressCounter = 0;
204 #if defined(_mk20dx128_) // ARM
205 // Clear the interrupt flag