mirror of
https://github.com/FreeRTOS/FreeRTOS-Kernel.git
synced 2026-01-21 01:00:35 -05:00
This commit is contained in:
Richard Barry
parent
5c64e1fad9
commit
4baf272c92
5062 changed files with 1554463 additions and 0 deletions
350
20100923-V6.1.0-RC2/Demo/dsPIC_MPLAB/lcd.c
Normal file
350
20100923-V6.1.0-RC2/Demo/dsPIC_MPLAB/lcd.c
Normal file
|
|
@ -0,0 +1,350 @@
|
|||
/*
|
||||
FreeRTOS V6.1.0 - Copyright (C) 2010 Real Time Engineers Ltd.
|
||||
|
||||
***************************************************************************
|
||||
* *
|
||||
* If you are: *
|
||||
* *
|
||||
* + New to FreeRTOS, *
|
||||
* + Wanting to learn FreeRTOS or multitasking in general quickly *
|
||||
* + Looking for basic training, *
|
||||
* + Wanting to improve your FreeRTOS skills and productivity *
|
||||
* *
|
||||
* then take a look at the FreeRTOS books - available as PDF or paperback *
|
||||
* *
|
||||
* "Using the FreeRTOS Real Time Kernel - a Practical Guide" *
|
||||
* http://www.FreeRTOS.org/Documentation *
|
||||
* *
|
||||
* A pdf reference manual is also available. Both are usually delivered *
|
||||
* to your inbox within 20 minutes to two hours when purchased between 8am *
|
||||
* and 8pm GMT (although please allow up to 24 hours in case of *
|
||||
* exceptional circumstances). 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 exception 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 Richard Barry, contact details for whom are available on the
|
||||
FreeRTOS WEB site.
|
||||
|
||||
1 tab == 4 spaces!
|
||||
|
||||
http://www.FreeRTOS.org - Documentation, latest information, license and
|
||||
contact details.
|
||||
|
||||
http://www.SafeRTOS.com - A version that is certified for use in safety
|
||||
critical systems.
|
||||
|
||||
http://www.OpenRTOS.com - Commercial support, development, porting,
|
||||
licensing and training services.
|
||||
*/
|
||||
|
||||
/* 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 lcdVERY_SHORT_DELAY ( 1 )
|
||||
#define lcdSHORT_DELAY ( 4 / portTICK_RATE_MS )
|
||||
#define lcdLONG_DELAY ( 15 / portTICK_RATE_MS )
|
||||
|
||||
/* LCD commands. */
|
||||
#define lcdCLEAR ( 0x01 )
|
||||
#define lcdHOME ( 0x02 )
|
||||
#define lcdLINE2 ( 0xc0 )
|
||||
|
||||
/* SFR that seems to be missing from the standard header files. */
|
||||
#define PMAEN *( ( unsigned short * ) 0x60c )
|
||||
|
||||
/* LCD R/W signal. */
|
||||
#define lcdRW LATDbits.LATD5
|
||||
|
||||
/* LCD lcdRS signal. */
|
||||
#define lcdRS LATBbits.LATB15
|
||||
|
||||
/* LCD lcdE signal . */
|
||||
#define lcdE LATDbits.LATD4
|
||||
|
||||
/* Control signal pin direction. */
|
||||
#define RW_TRIS TRISDbits.TRISD5
|
||||
#define RS_TRIS TRISBbits.TRISB15
|
||||
#define E_TRIS TRISDbits.TRISD4
|
||||
|
||||
/* Port for LCD data */
|
||||
#define lcdDATA LATE
|
||||
#define lcdDATAPORT PORTE
|
||||
|
||||
/* I/O setup for data Port. */
|
||||
#define TRISDATA TRISE
|
||||
|
||||
/* 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;
|
||||
|
||||
static void prvLCDCommand( portCHAR cCommand );
|
||||
static void prvLCDData( portCHAR cChar );
|
||||
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
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 )
|
||||
{
|
||||
prvLCDCommand( lcdHOME );
|
||||
}
|
||||
else
|
||||
{
|
||||
prvLCDCommand( lcdLINE2 );
|
||||
}
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
static void prvLCDCommand( portCHAR cCommand )
|
||||
{
|
||||
/* Prepare RD0 - RD7. */
|
||||
lcdDATA &= 0xFF00;
|
||||
|
||||
/* Command byte to lcd. */
|
||||
lcdDATA |= cCommand;
|
||||
|
||||
/* Ensure lcdRW is 0. */
|
||||
lcdRW = 0;
|
||||
lcdRS = 0;
|
||||
|
||||
/* Toggle lcdE line. */
|
||||
lcdE = 1;
|
||||
vTaskDelay( lcdVERY_SHORT_DELAY );
|
||||
lcdE = 0;
|
||||
|
||||
vTaskDelay( lcdSHORT_DELAY );
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
static void prvLCDData( portCHAR cChar )
|
||||
{
|
||||
/* ensure lcdRW is 0. */
|
||||
lcdRW = 0;
|
||||
|
||||
/* Assert register select to 1. */
|
||||
lcdRS = 1;
|
||||
|
||||
/* Prepare RD0 - RD7. */
|
||||
lcdDATA &= 0xFF00;
|
||||
|
||||
/* Data byte to lcd. */
|
||||
lcdDATA |= cChar;
|
||||
lcdE = 1;
|
||||
Nop();
|
||||
Nop();
|
||||
Nop();
|
||||
|
||||
/* Toggle lcdE signal. */
|
||||
lcdE = 0;
|
||||
|
||||
/* Negate register select to 0. */
|
||||
lcdRS = 0;
|
||||
|
||||
vTaskDelay( lcdVERY_SHORT_DELAY );
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
static void prvLCDPutString( portCHAR *pcString )
|
||||
{
|
||||
/* Write out each character with appropriate delay between each. */
|
||||
while( *pcString )
|
||||
{
|
||||
prvLCDData( *pcString );
|
||||
pcString++;
|
||||
vTaskDelay( lcdSHORT_DELAY );
|
||||
}
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
static void prvLCDClear( void )
|
||||
{
|
||||
prvLCDCommand( lcdCLEAR );
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
static void prvSetupLCD( void )
|
||||
{
|
||||
/* Wait for proper power up. */
|
||||
vTaskDelay( lcdLONG_DELAY );
|
||||
|
||||
/* Set initial states for the data and control pins */
|
||||
LATE &= 0xFF00;
|
||||
|
||||
/* R/W state set low. */
|
||||
lcdRW = 0;
|
||||
|
||||
/* lcdRS state set low. */
|
||||
lcdRS = 0;
|
||||
|
||||
/* lcdE state set low. */
|
||||
lcdE = 0;
|
||||
|
||||
/* Set data and control pins to outputs */
|
||||
TRISE &= 0xFF00;
|
||||
|
||||
/* lcdRW pin set as output. */
|
||||
RW_TRIS = 0;
|
||||
|
||||
/* lcdRS pin set as output. */
|
||||
RS_TRIS = 0;
|
||||
|
||||
/* lcdE pin set as output. */
|
||||
E_TRIS = 0;
|
||||
|
||||
/* 1st LCD initialization sequence */
|
||||
lcdDATA &= 0xFF00;
|
||||
lcdDATA |= 0x0038;
|
||||
lcdE = 1;
|
||||
Nop();
|
||||
Nop();
|
||||
Nop();
|
||||
|
||||
/* Toggle lcdE signal. */
|
||||
lcdE = 0;
|
||||
|
||||
vTaskDelay( lcdSHORT_DELAY );
|
||||
vTaskDelay( lcdSHORT_DELAY );
|
||||
vTaskDelay( lcdSHORT_DELAY );
|
||||
|
||||
/* 2nd LCD initialization sequence */
|
||||
lcdDATA &= 0xFF00;
|
||||
lcdDATA |= 0x0038;
|
||||
lcdE = 1;
|
||||
Nop();
|
||||
Nop();
|
||||
Nop();
|
||||
|
||||
/* Toggle lcdE signal. */
|
||||
lcdE = 0;
|
||||
|
||||
vTaskDelay( lcdSHORT_DELAY );
|
||||
|
||||
/* 3rd LCD initialization sequence */
|
||||
lcdDATA &= 0xFF00;
|
||||
lcdDATA |= 0x0038;
|
||||
lcdE = 1;
|
||||
Nop();
|
||||
Nop();
|
||||
Nop();
|
||||
|
||||
/* Toggle lcdE signal. */
|
||||
lcdE = 0;
|
||||
|
||||
vTaskDelay( lcdSHORT_DELAY );
|
||||
|
||||
|
||||
/* Function set. */
|
||||
prvLCDCommand( 0x38 );
|
||||
|
||||
/* Display on/off control, cursor blink off (0x0C). */
|
||||
prvLCDCommand( 0x0C );
|
||||
|
||||
/* Entry mode set (0x06). */
|
||||
prvLCDCommand( 0x06 );
|
||||
|
||||
prvLCDCommand( lcdCLEAR );
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
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 );
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
Loading…
Add table
Add a link
Reference in a new issue