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/*

    FreeRTOS V6.1.1 - Copyright (C) 2011 Real Time Engineers Ltd.

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    This file is part of the FreeRTOS distribution.

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*/

/*

 * This is a mini co-routine demo for the Rowley CrossFire LM3S102 development

 * board.  It makes use of the boards tri-colour LED and analogue input.

 *

 * Four co-routines are created - an 'I2C' co-routine and three 'flash'

 * co-routines.

 *

 * The I2C co-routine triggers an ADC conversion then blocks on a queue to

 * wait for the conversion result - which it receives on the queue directly

 * from the I2C interrupt service routine.  The conversion result is then

 * scalled to a delay period.  The I2C interrupt then wakes each of the

 * flash co-routines before itself delaying for the calculated period and

 * then repeating the whole process.

 *

 * When woken by the I2C co-routine the flash co-routines each block for

 * a given period, illuminate an LED for a fixed period, then go back to

 * sleep to wait for the next cycle.  The uxIndex parameter of the flash

 * co-routines is used to ensure that each flashes a different LED, and that

 * the delay periods are such that the LED's get flashed in sequence.

 */

/* Scheduler include files. */

#include "FreeRTOS.h"

#include "task.h"

#include "queue.h"

#include "croutine.h"

/* Demo application include files. */

#include "partest.h"

/* Library include files. */

#include "DriverLib.h"

/* States of the I2C master interface. */

#define mainI2C_IDLE       0

#define mainI2C_READ_1     1

#define mainI2C_READ_2     2

#define mainI2C_READ_DONE  3

#define mainZERO_LENGTH 0

/* Address of the A2D IC on the CrossFire board. */

#define mainI2CAddress  0x4D

/* The queue used to send data from the I2C ISR to the co-routine should never

contain more than one item as the same co-routine is used to trigger the I2C

activity. */

#define mainQUEUE_LENGTH 1

/* The CrossFire board contains a tri-colour LED. */

#define mainNUM_LEDs    3

/* The I2C co-routine has a higher priority than the flash co-routines.  This

is not really necessary as when the I2C co-routine is active the other

co-routines are delaying. */

#define mainI2c_CO_ROUTINE_PRIORITY 1

/* The current state of the I2C master. */

static volatile unsigned portBASE_TYPE uxState = mainI2C_IDLE;

/* The delay period derived from the A2D value. */

static volatile portBASE_TYPE uxDelay = 250;

/* The queue used to communicate between the I2C interrupt and the I2C

co-routine. */

static xQueueHandle xADCQueue;

/* The queue used to synchronise the flash co-routines. */

static xQueueHandle xDelayQueue;

/*

 * Sets up the PLL, I2C and GPIO used by the demo.

 */

static void prvSetupHardware( void );

/* The co-routines as described at the top of the file. */

static void vI2CCoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex );

static void vFlashCoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex );

/*-----------------------------------------------------------*/

int main( void )

{

unsigned portBASE_TYPE uxCoRoutine;

        /* Setup all the hardware used by this demo. */

        prvSetupHardware();

        /* Create the queue used to communicate between the ISR and I2C co-routine.

        This can only ever contain one value. */

        xADCQueue = xQueueCreate( mainQUEUE_LENGTH, sizeof( portTickType ) );

        /* Create the queue used to synchronise the flash co-routines.  The queue

        is used to trigger three tasks, but is for synchronisation only and does

        not pass any data.  It therefore has three position each of zero length. */

        xDelayQueue = xQueueCreate( mainNUM_LEDs, mainZERO_LENGTH );

        /* Create the co-routine that initiates the i2c. */

        xCoRoutineCreate( vI2CCoRoutine, mainI2c_CO_ROUTINE_PRIORITY, 0 );

        /* Create the flash co-routines. */

        for( uxCoRoutine = 0; uxCoRoutine < mainNUM_LEDs; uxCoRoutine++ )

        {

                xCoRoutineCreate( vFlashCoRoutine, tskIDLE_PRIORITY, uxCoRoutine );

        }

        /* Start the scheduler.  From this point on the co-routines should

        execute. */

        vTaskStartScheduler();

        /* Should not get here unless we did not have enough memory to start the

        scheduler. */

        for( ;; );

        return 0;

}

/*-----------------------------------------------------------*/

static void prvSetupHardware( void )

{

        /* Setup the PLL. */

        SysCtlClockSet( SYSCTL_SYSDIV_10 | SYSCTL_USE_PLL | SYSCTL_OSC_MAIN | SYSCTL_XTAL_6MHZ );

        /* Enable the I2C used to read the pot. */

        SysCtlPeripheralEnable( SYSCTL_PERIPH_I2C );

        SysCtlPeripheralEnable( SYSCTL_PERIPH_GPIOB );

        GPIOPinTypeI2C( GPIO_PORTB_BASE, GPIO_PIN_2 | GPIO_PIN_3 );

        /* Initialize the I2C master. */

        I2CMasterInit( I2C_MASTER_BASE, pdFALSE );

        /* Enable the I2C master interrupt. */

        I2CMasterIntEnable( I2C_MASTER_BASE );

    IntEnable( INT_I2C );

        /* Initialise the hardware used to talk to the LED's. */

        vParTestInitialise();

}

/*-----------------------------------------------------------*/

static void vI2CCoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex )

{

portTickType xADCResult;

static portBASE_TYPE xResult = 0, xMilliSecs, xLED;

        crSTART( xHandle );

        for( ;; )

        {

                /* Start the I2C off to read the ADC. */

                uxState = mainI2C_READ_1;

                I2CMasterSlaveAddrSet( I2C_MASTER_BASE, mainI2CAddress, pdTRUE );

                I2CMasterControl( I2C_MASTER_BASE, I2C_MASTER_CMD_BURST_RECEIVE_START );

                /* Wait to receive the conversion result. */

                crQUEUE_RECEIVE( xHandle, xADCQueue, &xADCResult, portMAX_DELAY, &xResult );

                /* Scale the result to give a useful range of values for a visual

                demo. */

                xADCResult >>= 2;

                xMilliSecs = xADCResult / portTICK_RATE_MS;

                /* The delay is split between the four co-routines so they remain in

                synch. */

                uxDelay = xMilliSecs / ( mainNUM_LEDs + 1 );

                /* Trigger each of the flash co-routines. */

                for( xLED = 0; xLED < mainNUM_LEDs; xLED++ )

                {

                        crQUEUE_SEND( xHandle, xDelayQueue, &xLED, 0, &xResult );

                }

                /* Wait for the full delay time then start again.  This delay is long

                enough to ensure the flash co-routines have done their thing and gone

                back to sleep. */

                crDELAY( xHandle, xMilliSecs );

        }

        crEND();

}

/*-----------------------------------------------------------*/

static void vFlashCoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex )

{

portBASE_TYPE xResult, xNothing;

        crSTART( xHandle );

        for( ;; )

        {

                /* Wait for start of next round. */

                crQUEUE_RECEIVE( xHandle, xDelayQueue, &xNothing, portMAX_DELAY, &xResult );

                /* Wait until it is this co-routines turn to flash. */

                crDELAY( xHandle, uxDelay * uxIndex );

                /* Turn on the LED for a fixed period. */

                vParTestSetLED( uxIndex, pdTRUE );

                crDELAY( xHandle, uxDelay );

                vParTestSetLED( uxIndex, pdFALSE );

                /* Go back and wait for the next round. */

        }

        crEND();

}

/*-----------------------------------------------------------*/

void vI2C_ISR(void)

{

static portTickType xReading;

        /* Clear the interrupt. */

        I2CMasterIntClear( I2C_MASTER_BASE );

        /* Determine what to do based on the current uxState. */

        switch (uxState)

        {

                case mainI2C_IDLE:              break;

                case mainI2C_READ_1:    /* Read ADC result high byte. */

                                                                xReading = I2CMasterDataGet( I2C_MASTER_BASE );

                                                                xReading <<= 8;

                                                                /* Continue the burst read. */

                                                                I2CMasterControl( I2C_MASTER_BASE, I2C_MASTER_CMD_BURST_RECEIVE_CONT );

                                                                uxState = mainI2C_READ_2;

                                                                break;

                case mainI2C_READ_2:    /* Read ADC result low byte. */

                                                                xReading |= I2CMasterDataGet( I2C_MASTER_BASE );

                                                                /* Finish the burst read. */

                                                                I2CMasterControl( I2C_MASTER_BASE, I2C_MASTER_CMD_BURST_RECEIVE_FINISH );

                                                                uxState = mainI2C_READ_DONE;

                                                                break;

                case mainI2C_READ_DONE: /* Complete. */

                                                                I2CMasterDataGet( I2C_MASTER_BASE );

                                                                uxState = mainI2C_IDLE;

                                                                /* Send the result to the co-routine. */

                                crQUEUE_SEND_FROM_ISR( xADCQueue, &xReading, pdFALSE );

                                                                break;

        }

}

/*-----------------------------------------------------------*/

void vApplicationIdleHook( void )

{

        for( ;; )

        {

                vCoRoutineSchedule();

        }

}