/* FreeRTOS V8.2.0rc1 - Copyright (C) 2014 Real Time Engineers Ltd. All rights reserved VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. This file is part of the FreeRTOS distribution. FreeRTOS is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License (version 2) as published by the Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception. >>! NOTE: The modification to the GPL is included to allow you to !<< >>! distribute a combined work that includes FreeRTOS without being !<< >>! obliged to provide the source code for proprietary components !<< >>! outside of the FreeRTOS kernel. !<< FreeRTOS 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. Full license text is available on the following link: http://www.freertos.org/a00114.html 1 tab == 4 spaces! *************************************************************************** * * * Having a problem? Start by reading the FAQ "My application does * * not run, what could be wrong?". Have you defined configASSERT()? * * * * http://www.FreeRTOS.org/FAQHelp.html * * * *************************************************************************** *************************************************************************** * * * FreeRTOS provides completely free yet professionally developed, * * robust, strictly quality controlled, supported, and cross * * platform software that is more than just the market leader, it * * is the industry's de facto standard. * * * * Help yourself get started quickly while simultaneously helping * * to support the FreeRTOS project by purchasing a FreeRTOS * * tutorial book, reference manual, or both: * * http://www.FreeRTOS.org/Documentation * * * *************************************************************************** *************************************************************************** * * * Investing in training allows your team to be as productive as * * possible as early as possible, lowering your overall development * * cost, and enabling you to bring a more robust product to market * * earlier than would otherwise be possible. Richard Barry is both * * the architect and key author of FreeRTOS, and so also the world's * * leading authority on what is the world's most popular real time * * kernel for deeply embedded MCU designs. Obtaining your training * * from Richard ensures your team will gain directly from his in-depth * * product knowledge and years of usage experience. Contact Real Time * * Engineers Ltd to enquire about the FreeRTOS Masterclass, presented * * by Richard Barry: http://www.FreeRTOS.org/contact * * *************************************************************************** *************************************************************************** * * * You are receiving this top quality software for free. Please play * * fair and reciprocate by reporting any suspected issues and * * participating in the community forum: * * http://www.FreeRTOS.org/support * * * * Thank you! * * * *************************************************************************** http://www.FreeRTOS.org - Documentation, books, training, latest versions, license and Real Time Engineers Ltd. contact details. http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products, including FreeRTOS+Trace - an indispensable productivity tool, a DOS compatible FAT file system, and our tiny thread aware UDP/IP stack. http://www.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate. Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS. http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High Integrity Systems ltd. to sell under the OpenRTOS brand. Low cost OpenRTOS licenses offer ticketed support, indemnification and commercial middleware. http://www.SafeRTOS.com - High Integrity Systems also provide a safety engineered and independently SIL3 certified version for use in safety and mission critical applications that require provable dependability. 1 tab == 4 spaces! */ /* Changes from V3.0.0 + ISRcode is pulled inline and portTICKisr() is therefore deleted from this file. + Prescaler logic for Timer1 added to allow for a wider range of TickRates. Changes from V3.0.1 */ #include #include /* IO port constants. */ #define portBIT_SET (1) #define portBIT_CLEAR (0) /* * Hardware setup for the tick. * We use a compare match on timer1. Depending on MPU-frequency * and requested tickrate, a prescaled value with a matching * prescaler are determined. */ #define portTIMER_COMPARE_BASE ((APROCFREQ/4)/configTICK_RATE_HZ) #if portTIMER_COMPARE_BASE < 0x10000 #define portTIMER_COMPARE_VALUE (portTIMER_COMPARE_BASE) #define portTIMER_COMPARE_PS1 (portBIT_CLEAR) #define portTIMER_COMPARE_PS0 (portBIT_CLEAR) #elif portTIMER_COMPARE_BASE < 0x20000 #define portTIMER_COMPARE_VALUE (portTIMER_COMPARE_BASE / 2) #define portTIMER_COMPARE_PS1 (portBIT_CLEAR) #define portTIMER_COMPARE_PS0 (portBIT_SET) #elif portTIMER_COMPARE_BASE < 0x40000 #define portTIMER_COMPARE_VALUE (portTIMER_COMPARE_BASE / 4) #define portTIMER_COMPARE_PS1 (portBIT_SET) #define portTIMER_COMPARE_PS0 (portBIT_CLEAR) #elif portTIMER_COMPARE_BASE < 0x80000 #define portTIMER_COMPARE_VALUE (portTIMER_COMPARE_BASE / 8) #define portTIMER_COMPARE_PS1 (portBIT_SET) #define portTIMER_COMPARE_PS0 (portBIT_SET) #else #error "TickRate out of range" #endif /*-----------------------------------------------------------*/ /* * Setup a timer for a regular tick. */ void portSetupTick( void ) { /* * Interrupts are disabled when this function is called. */ /* * Setup CCP1 * Provide the tick interrupt using a compare match on timer1. */ /* * Set the compare match value. */ CCPR1H = ( uint8_t ) ( ( portTIMER_COMPARE_VALUE >> 8 ) & 0xff ); CCPR1L = ( uint8_t ) ( portTIMER_COMPARE_VALUE & 0xff ); /* * Set Compare Special Event Trigger Mode */ bCCP1M3 = portBIT_SET; bCCP1M2 = portBIT_CLEAR; bCCP1M1 = portBIT_SET; bCCP1M0 = portBIT_SET; /* * Enable CCP1 interrupt */ bCCP1IE = portBIT_SET; /* * We are only going to use the global interrupt bit, so disable * interruptpriorities and enable peripheral interrupts. */ bIPEN = portBIT_CLEAR; bPEIE = portBIT_SET; /* * Set up timer1 * It will produce the system tick. */ /* * Clear the time count */ TMR1H = ( uint8_t ) 0x00; TMR1L = ( uint8_t ) 0x00; /* * Setup the timer */ bRD16 = portBIT_SET; // 16-bit bT1CKPS1 = portTIMER_COMPARE_PS1; // prescaler bT1CKPS0 = portTIMER_COMPARE_PS0; // prescaler bT1OSCEN = portBIT_SET; // Oscillator enable bT1SYNC = portBIT_SET; // No external clock sync bTMR1CS = portBIT_CLEAR; // Internal clock bTMR1ON = portBIT_SET; // Start timer1 }