/* FreeRTOS V8.0.0 - 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! */ /* peripheral library include */ #include /* Scheduler includes. */ #include "FreeRTOS.h" #include "task.h" #include "queue.h" /* Demo includes. */ #include "lcd.h" /* * The LCD is written to by more than one task so is controlled by this * 'gatekeeper' task. This is the only task that is actually permitted to * access the LCD directly. Other tasks wanting to display a message send * the message to the gatekeeper. */ static void vLCDTask( void *pvParameters ); /* * Setup the peripherals required to communicate with the LCD. */ static void prvSetupLCD( void ); /* * Move to the first (0) or second (1) row of the LCD. */ static void prvLCDGotoRow( unsigned short usRow ); /* * Write a string of text to the LCD. */ static void prvLCDPutString( char *pcString ); /* * Clear the LCD. */ static void prvLCDClear( void ); /*-----------------------------------------------------------*/ /* Brief delay to permit the LCD to catch up with commands. */ #define lcdVERY_SHORT_DELAY ( 1 ) #define lcdSHORT_DELAY ( 8 / portTICK_PERIOD_MS ) #define lcdLONG_DELAY ( 15 / portTICK_PERIOD_MS ) /* LCD specific definitions. */ #define LCD_CLEAR_DISPLAY_CMD 0x01 #define LCD_CURSOR_HOME_CMD 0x02 #define LCD_ENTRY_MODE_CMD 0x04 #define LCD_ENTRY_MODE_INCREASE 0x02 #define LCD_DISPLAY_CTRL_CMD 0x08 #define LCD_DISPLAY_CTRL_DISPLAY_ON 0x04 #define LCD_FUNCTION_SET_CMD 0x20 #define LCD_FUNCTION_SET_8_BITS 0x10 #define LCD_FUNCTION_SET_2_LINES 0x08 #define LCD_FUNCTION_SET_LRG_FONT 0x04 #define LCD_NEW_LINE 0xC0 #define LCD_COMMAND_ADDRESS 0x00 #define LCD_DATA_ADDRESS 0x01 /* The length of the queue used to send messages to the LCD gatekeeper task. */ #define lcdQUEUE_SIZE 3 /*-----------------------------------------------------------*/ /* The queue used to send messages to the LCD task. */ QueueHandle_t xLCDQueue; /* LCD access functions. */ static void prvLCDCommand( char cCommand ); static void prvLCDData( char cChar ); /*-----------------------------------------------------------*/ QueueHandle_t xStartLCDTask( void ) { /* Create the queue used by the LCD task. Messages for display on the LCD are received via this queue. */ xLCDQueue = xQueueCreate( lcdQUEUE_SIZE, sizeof( xLCDMessage )); /* Start the task that will write to the LCD. The LCD hardware is initialised from within the task itself so delays can be used. */ xTaskCreate( vLCDTask, "LCD", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY + 1, NULL ); return xLCDQueue; } /*-----------------------------------------------------------*/ static void prvLCDGotoRow( unsigned short usRow ) { if(usRow == 0) { prvLCDCommand( LCD_CURSOR_HOME_CMD ); } else { prvLCDCommand( LCD_NEW_LINE ); } } /*-----------------------------------------------------------*/ static void prvLCDCommand( char cCommand ) { PMPSetAddress( LCD_COMMAND_ADDRESS ); PMPMasterWrite( cCommand ); vTaskDelay( lcdSHORT_DELAY ); } /*-----------------------------------------------------------*/ static void prvLCDData( char cChar ) { PMPSetAddress( LCD_DATA_ADDRESS ); PMPMasterWrite( cChar ); vTaskDelay( lcdVERY_SHORT_DELAY ); } /*-----------------------------------------------------------*/ static void prvLCDPutString( char *pcString ) { /* Write out each character with appropriate delay between each. */ while(*pcString) { prvLCDData(*pcString); pcString++; vTaskDelay(lcdSHORT_DELAY); } } /*-----------------------------------------------------------*/ static void prvLCDClear(void) { prvLCDCommand(LCD_CLEAR_DISPLAY_CMD); } /*-----------------------------------------------------------*/ static void prvSetupLCD(void) { /* Wait for proper power up. */ vTaskDelay( lcdLONG_DELAY ); /* Open the PMP port */ mPMPOpen((PMP_ON | PMP_READ_WRITE_EN | PMP_CS2_CS1_EN | PMP_LATCH_POL_HI | PMP_CS2_POL_HI | PMP_CS1_POL_HI | PMP_WRITE_POL_HI | PMP_READ_POL_HI), (PMP_MODE_MASTER1 | PMP_WAIT_BEG_4 | PMP_WAIT_MID_15 | PMP_WAIT_END_4), PMP_PEN_0, 0); /* Wait for the LCD to power up correctly. */ vTaskDelay( lcdLONG_DELAY ); vTaskDelay( lcdLONG_DELAY ); vTaskDelay( lcdLONG_DELAY ); /* Set up the LCD function. */ prvLCDCommand( LCD_FUNCTION_SET_CMD | LCD_FUNCTION_SET_8_BITS | LCD_FUNCTION_SET_2_LINES | LCD_FUNCTION_SET_LRG_FONT ); /* Turn the display on. */ prvLCDCommand( LCD_DISPLAY_CTRL_CMD | LCD_DISPLAY_CTRL_DISPLAY_ON ); /* Clear the display. */ prvLCDCommand( LCD_CLEAR_DISPLAY_CMD ); vTaskDelay( lcdLONG_DELAY ); /* Increase the cursor. */ prvLCDCommand( LCD_ENTRY_MODE_CMD | LCD_ENTRY_MODE_INCREASE ); vTaskDelay( lcdLONG_DELAY ); vTaskDelay( lcdLONG_DELAY ); vTaskDelay( lcdLONG_DELAY ); } /*-----------------------------------------------------------*/ static void vLCDTask(void *pvParameters) { xLCDMessage xMessage; unsigned short usRow = 0; /* Initialise the hardware. This uses delays so must not be called prior to the scheduler being started. */ prvSetupLCD(); /* Welcome message. */ prvLCDPutString( "www.FreeRTOS.org" ); for(;;) { /* Wait for a message to arrive that requires displaying. */ while( xQueueReceive( xLCDQueue, &xMessage, portMAX_DELAY ) != pdPASS ); /* Clear the current display value. */ prvLCDClear(); /* Switch rows each time so we can see that the display is still being updated. */ prvLCDGotoRow( usRow & 0x01 ); usRow++; prvLCDPutString( xMessage.pcMessage ); /* Delay the requested amount of time to ensure the text just written to the LCD is not overwritten. */ vTaskDelay( xMessage.xMinDisplayTime ); } }