| /* | |
| 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! | |
| */ | |
| /*----------------------------------------------------------- | |
| * Implementation of functions defined in portable.h for the Tern EE 186 | |
| * port. | |
| *----------------------------------------------------------*/ | |
| /* Library includes. */ | |
| #include <embedded.h> | |
| #include <ae.h> | |
| /* Scheduler includes. */ | |
| #include "FreeRTOS.h" | |
| #include "task.h" | |
| #include "portasm.h" | |
| /* The timer increments every four clocks, hence the divide by 4. */ | |
| #define portTIMER_COMPARE ( uint16_t ) ( ( configCPU_CLOCK_HZ / configTICK_RATE_HZ ) / ( uint32_t ) 4 ) | |
| /* From the RDC data sheet. */ | |
| #define portENABLE_TIMER_AND_INTERRUPT ( uint16_t ) 0xe001 | |
| /* Interrupt control. */ | |
| #define portEIO_REGISTER 0xff22 | |
| #define portCLEAR_INTERRUPT 0x0008 | |
| /* Setup the hardware to generate the required tick frequency. */ | |
| static void prvSetupTimerInterrupt( void ); | |
| /* The ISR used depends on whether the preemptive or cooperative scheduler | |
| is being used. */ | |
| #if( configUSE_PREEMPTION == 1 ) | |
| /* Tick service routine used by the scheduler when preemptive scheduling is | |
| being used. */ | |
| static void __interrupt __far prvPreemptiveTick( void ); | |
| #else | |
| /* Tick service routine used by the scheduler when cooperative scheduling is | |
| being used. */ | |
| static void __interrupt __far prvNonPreemptiveTick( void ); | |
| #endif | |
| /* Trap routine used by taskYIELD() to manually cause a context switch. */ | |
| static void __interrupt __far prvYieldProcessor( void ); | |
| /* The timer initialisation functions leave interrupts enabled, | |
| which is not what we want. This ISR is installed temporarily in case | |
| the timer fires before we get a change to disable interrupts again. */ | |
| static void __interrupt __far prvDummyISR( void ); | |
| /*-----------------------------------------------------------*/ | |
| /* See header file for description. */ | |
| StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t pxCode, void *pvParameters ) | |
| { | |
| StackType_t DS_Reg = 0; | |
| /* Place a few bytes of known values on the bottom of the stack. | |
| This is just useful for debugging. */ | |
| *pxTopOfStack = 0x1111; | |
| pxTopOfStack--; | |
| *pxTopOfStack = 0x2222; | |
| pxTopOfStack--; | |
| *pxTopOfStack = 0x3333; | |
| pxTopOfStack--; | |
| /* We are going to start the scheduler using a return from interrupt | |
| instruction to load the program counter, so first there would be the | |
| function call with parameters preamble. */ | |
| *pxTopOfStack = FP_SEG( pvParameters ); | |
| pxTopOfStack--; | |
| *pxTopOfStack = FP_OFF( pvParameters ); | |
| pxTopOfStack--; | |
| *pxTopOfStack = FP_SEG( pxCode ); | |
| pxTopOfStack--; | |
| *pxTopOfStack = FP_OFF( pxCode ); | |
| pxTopOfStack--; | |
| /* Next the status register and interrupt return address. */ | |
| *pxTopOfStack = portINITIAL_SW; | |
| pxTopOfStack--; | |
| *pxTopOfStack = FP_SEG( pxCode ); | |
| pxTopOfStack--; | |
| *pxTopOfStack = FP_OFF( pxCode ); | |
| pxTopOfStack--; | |
| /* The remaining registers would be pushed on the stack by our context | |
| switch function. These are loaded with values simply to make debugging | |
| easier. */ | |
| *pxTopOfStack = ( StackType_t ) 0xAAAA; /* AX */ | |
| pxTopOfStack--; | |
| *pxTopOfStack = ( StackType_t ) 0xBBBB; /* BX */ | |
| pxTopOfStack--; | |
| *pxTopOfStack = ( StackType_t ) 0xCCCC; /* CX */ | |
| pxTopOfStack--; | |
| *pxTopOfStack = ( StackType_t ) 0xDDDD; /* DX */ | |
| pxTopOfStack--; | |
| *pxTopOfStack = ( StackType_t ) 0xEEEE; /* ES */ | |
| pxTopOfStack--; | |
| /* We need the true data segment. */ | |
| __asm{ MOV DS_Reg, DS }; | |
| *pxTopOfStack = DS_Reg; /* DS */ | |
| pxTopOfStack--; | |
| *pxTopOfStack = ( StackType_t ) 0x0123; /* SI */ | |
| pxTopOfStack--; | |
| *pxTopOfStack = ( StackType_t ) 0xDDDD; /* DI */ | |
| pxTopOfStack--; | |
| *pxTopOfStack = ( StackType_t ) 0xBBBB; /* BP */ | |
| return pxTopOfStack; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| BaseType_t xPortStartScheduler( void ) | |
| { | |
| /* This is called with interrupts already disabled. */ | |
| /* Put our manual switch (yield) function on a known | |
| vector. */ | |
| setvect( portSWITCH_INT_NUMBER, prvYieldProcessor ); | |
| /* Setup the tick interrupt. */ | |
| prvSetupTimerInterrupt(); | |
| /* Kick off the scheduler by setting up the context of the first task. */ | |
| portFIRST_CONTEXT(); | |
| /* Should not get here! */ | |
| return pdFALSE; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| static void __interrupt __far prvDummyISR( void ) | |
| { | |
| /* The timer initialisation functions leave interrupts enabled, | |
| which is not what we want. This ISR is installed temporarily in case | |
| the timer fires before we get a change to disable interrupts again. */ | |
| outport( portEIO_REGISTER, portCLEAR_INTERRUPT ); | |
| } | |
| /*-----------------------------------------------------------*/ | |
| /* The ISR used depends on whether the preemptive or cooperative scheduler | |
| is being used. */ | |
| #if( configUSE_PREEMPTION == 1 ) | |
| static void __interrupt __far prvPreemptiveTick( void ) | |
| { | |
| /* Get the scheduler to update the task states following the tick. */ | |
| if( xTaskIncrementTick() != pdFALSE ) | |
| { | |
| /* Switch in the context of the next task to be run. */ | |
| portSWITCH_CONTEXT(); | |
| } | |
| /* Reset interrupt. */ | |
| outport( portEIO_REGISTER, portCLEAR_INTERRUPT ); | |
| } | |
| #else | |
| static void __interrupt __far prvNonPreemptiveTick( void ) | |
| { | |
| /* Same as preemptive tick, but the cooperative scheduler is being used | |
| so we don't have to switch in the context of the next task. */ | |
| xTaskIncrementTick(); | |
| /* Reset interrupt. */ | |
| outport( portEIO_REGISTER, portCLEAR_INTERRUPT ); | |
| } | |
| #endif | |
| /*-----------------------------------------------------------*/ | |
| static void __interrupt __far prvYieldProcessor( void ) | |
| { | |
| /* Switch in the context of the next task to be run. */ | |
| portSWITCH_CONTEXT(); | |
| } | |
| /*-----------------------------------------------------------*/ | |
| void vPortEndScheduler( void ) | |
| { | |
| /* Not implemented. */ | |
| } | |
| /*-----------------------------------------------------------*/ | |
| static void prvSetupTimerInterrupt( void ) | |
| { | |
| const uint16_t usTimerACompare = portTIMER_COMPARE, usTimerAMode = portENABLE_TIMER_AND_INTERRUPT; | |
| const uint16_t usT2_IRQ = 0x13; | |
| /* Configure the timer, the dummy handler is used here as the init | |
| function leaves interrupts enabled. */ | |
| t2_init( usTimerAMode, usTimerACompare, prvDummyISR ); | |
| /* Disable interrupts again before installing the real handlers. */ | |
| portDISABLE_INTERRUPTS(); | |
| #if( configUSE_PREEMPTION == 1 ) | |
| /* Tick service routine used by the scheduler when preemptive scheduling is | |
| being used. */ | |
| setvect( usT2_IRQ, prvPreemptiveTick ); | |
| #else | |
| /* Tick service routine used by the scheduler when cooperative scheduling is | |
| being used. */ | |
| setvect( usT2_IRQ, prvNonPreemptiveTick ); | |
| #endif | |
| } | |