| /* | |
| FreeRTOS V8.1.2 - Copyright (C) 2014 Real Time Engineers Ltd. | |
| All rights reserved | |
| VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. | |
| *************************************************************************** | |
| * * | |
| * FreeRTOS provides completely free yet professionally developed, * | |
| * robust, strictly quality controlled, supported, and cross * | |
| * platform software that has become a de facto standard. * | |
| * * | |
| * Help yourself get started quickly and support the FreeRTOS * | |
| * project by purchasing a FreeRTOS tutorial book, reference * | |
| * manual, or both from: http://www.FreeRTOS.org/Documentation * | |
| * * | |
| * Thank you! * | |
| * * | |
| *************************************************************************** | |
| 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 from 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?" * | |
| * * | |
| * http://www.FreeRTOS.org/FAQHelp.html * | |
| * * | |
| *************************************************************************** | |
| 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.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High | |
| Integrity Systems to sell under the OpenRTOS brand. Low cost OpenRTOS | |
| licenses offer ticketed support, indemnification and 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 <FreeRTOS.h> | |
| #include <task.h> | |
| /* 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 | |
| } |