/* | |
FreeRTOS V7.4.1 - Copyright (C) 2013 Real Time Engineers Ltd. | |
FEATURES AND PORTS ARE ADDED TO FREERTOS ALL THE TIME. PLEASE VISIT | |
http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. | |
*************************************************************************** | |
* * | |
* FreeRTOS tutorial books are available in pdf and paperback. * | |
* Complete, revised, and edited pdf reference manuals are also * | |
* available. * | |
* * | |
* Purchasing FreeRTOS documentation will not only help you, by * | |
* ensuring you get running as quickly as possible and with an * | |
* in-depth knowledge of how to use FreeRTOS, it will also help * | |
* the FreeRTOS project to continue with its mission of providing * | |
* professional grade, cross platform, de facto standard solutions * | |
* for microcontrollers - completely free of charge! * | |
* * | |
* >>> See http://www.FreeRTOS.org/Documentation for details. <<< * | |
* * | |
* Thank you for using FreeRTOS, and thank you for your support! * | |
* * | |
*************************************************************************** | |
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. See the GNU General Public License for more | |
details. You should have received a copy of the GNU General Public License | |
and the FreeRTOS license exception along with FreeRTOS; if not it can be | |
viewed here: http://www.freertos.org/a00114.html and also obtained by | |
writing to Real Time Engineers Ltd., contact details for whom are available | |
on the FreeRTOS WEB site. | |
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, and our new | |
fully thread aware and reentrant UDP/IP stack. | |
http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High | |
Integrity Systems, who sell the code with commercial support, | |
indemnification and middleware, under the OpenRTOS brand. | |
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. | |
*/ | |
/* 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 portSHORT usRow ); | |
/* | |
* Write a string of text to the LCD. | |
*/ | |
static void prvLCDPutString( portCHAR *pcString ); | |
/* | |
* Clear the LCD. | |
*/ | |
static void prvLCDClear( void ); | |
/*-----------------------------------------------------------*/ | |
/* Brief delay to permit the LCD to catch up with commands. */ | |
#define lcdSHORT_DELAY 3 | |
/* SFR that seems to be missing from the standard header files. */ | |
#define PMAEN *( ( unsigned short * ) 0x60c ) | |
/* LCD commands. */ | |
#define lcdDEFAULT_FUNCTION 0x3c | |
#define lcdDISPLAY_CONTROL 0x0c | |
#define lcdCLEAR_DISPLAY 0x01 | |
#define lcdENTRY_MODE 0x06 | |
/* 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. */ | |
xQueueHandle xLCDQueue; | |
/*-----------------------------------------------------------*/ | |
xQueueHandle 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, ( signed portCHAR * ) "LCD", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY + 1, NULL ); | |
return xLCDQueue; | |
} | |
/*-----------------------------------------------------------*/ | |
static void prvLCDGotoRow( unsigned portSHORT usRow ) | |
{ | |
if( usRow == 0 ) | |
{ | |
PMADDR = 0x0000; | |
PMDIN1 = 0x02; | |
} | |
else | |
{ | |
PMADDR = 0x0000; | |
PMDIN1 = 0xc0; | |
} | |
vTaskDelay( lcdSHORT_DELAY ); | |
} | |
/*-----------------------------------------------------------*/ | |
static void prvLCDPutString( portCHAR *pcString ) | |
{ | |
/* Write out each character with appropriate delay between each. */ | |
while( *pcString ) | |
{ | |
PMADDR = 0x0001; | |
PMDIN1 = *pcString; | |
pcString++; | |
vTaskDelay( lcdSHORT_DELAY ); | |
} | |
} | |
/*-----------------------------------------------------------*/ | |
static void prvLCDClear( void ) | |
{ | |
/* Clear the display. */ | |
PMADDR = 0x0000; | |
PMDIN1 = lcdCLEAR_DISPLAY; | |
vTaskDelay( lcdSHORT_DELAY ); | |
} | |
/*-----------------------------------------------------------*/ | |
static void prvSetupLCD( void ) | |
{ | |
/* Setup the PMP. */ | |
PMCON = 0x83BF; | |
PMMODE = 0x3FF; | |
PMAEN = 1; | |
PMADDR = 0x0000; | |
vTaskDelay( lcdSHORT_DELAY ); | |
/* Set the default function. */ | |
PMDIN1 = lcdDEFAULT_FUNCTION; | |
vTaskDelay( lcdSHORT_DELAY ); | |
/* Set the display control. */ | |
PMDIN1 = lcdDISPLAY_CONTROL; | |
vTaskDelay( lcdSHORT_DELAY ); | |
/* Clear the display. */ | |
PMDIN1 = lcdCLEAR_DISPLAY; | |
vTaskDelay( lcdSHORT_DELAY ); | |
/* Set the entry mode. */ | |
PMDIN1 = lcdENTRY_MODE; | |
vTaskDelay( lcdSHORT_DELAY ); | |
} | |
/*-----------------------------------------------------------*/ | |
static void vLCDTask( void *pvParameters ) | |
{ | |
xLCDMessage xMessage; | |
unsigned portSHORT 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 ); | |
} | |
} | |