/*********************************************************************
 *
 *                  UART Interrupt Example
 *
 *********************************************************************
 * FileName:        uart_interrupt.c
 * Dependencies:
 * Processor:       PIC32
 *
 * Complier:        MPLAB C32
 *                  MPLAB IDE
 * Company:         Microchip Technology Inc.
 *
 * Software License Agreement
 *
 * The software supplied herewith by Microchip Technology Incorporated
 * (the Company) for its PIC32 Microcontroller is intended
 * and supplied to you, the Companys customer, for use solely and
 * exclusively on Microchip PIC32 Microcontroller products.
 * The software is owned by the Company and/or its supplier, and is
 * protected under applicable copyright laws. All rights are reserved.
 * Any use in violation of the foregoing restrictions may subject the
 * user to criminal sanctions under applicable laws, as well as to
 * civil liability for the breach of the terms and conditions of this
 * license.
 *
 * THIS SOFTWARE IS PROVIDED IN AN AS IS CONDITION. NO WARRANTIES,
 * WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED
 * TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. THE COMPANY SHALL NOT,
 * IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL OR
 * CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
 *
 *
 * $Id: uart_interrupt.c 9390 2008-06-16 23:43:04Z rajbhartin $
 * $Name: x.x $
 *
 **********************************************************************/

/***********************************************************************************
									UART Interrupt Example README
 ***********************************************************************************
 * Objective: Become familiar with PIC32MX tool suite and understand
 *		 	  basic UART Interrupt operations.
 *
 * Tools:
 *			1. MPLAB with PIC32MX support
 *			2. C32 Compiler
 *			3. Explorer 16 Rev 4 or 5 board.
 *			4. RS-232 Cable
 *			5. A Terminal program for Windows - HyperTerminal
 *
 *
 ***********************************************************************************
 ***********************************************************************************/

#include <plib.h>					// Peripheral Library


// *****************************************************************************
// *****************************************************************************
// Section: Configuration bits
// SYSCLK = 80 MHz (8MHz Crystal/ FPLLIDIV * FPLLMUL / FPLLODIV)
// PBCLK = 40 MHz
// Primary Osc w/PLL (XT+,HS+,EC+PLL)
// WDT OFF
// Other options are don't care
// *****************************************************************************
// *****************************************************************************
#pragma config FPLLMUL = MUL_20, FPLLIDIV = DIV_2, FPLLODIV = DIV_1, FWDTEN = OFF
#pragma config POSCMOD = HS, FNOSC = PRIPLL, FPBDIV = DIV_1

// *****************************************************************************
// *****************************************************************************
// Section: System Macros
// *****************************************************************************
// *****************************************************************************
#define	GetSystemClock() 			(80000000ul)
#define	GetPeripheralClock()		(GetSystemClock()/(1 << OSCCONbits.PBDIV))
#define	GetInstructionClock()		(GetSystemClock())

#define DESIRED_BAUDRATE    	(9600)      //The desired BaudRate


void WriteString(const char *string);

int main(void)
{

	// Configure the device for maximum performance but do not change the PBDIV
	// Given the options, this function will change the flash wait states, RAM
	// wait state and enable prefetch cache but will not change the PBDIV.
	// The PBDIV value is already set via the pragma FPBDIV option above..
	SYSTEMConfig(GetSystemClock(), SYS_CFG_WAIT_STATES | SYS_CFG_PCACHE);

	mPORTAClearBits(BIT_7); 		// Turn off RA7 on startup.
	mPORTASetPinsDigitalOut(BIT_7);	// Make RA7 as output.


	// Explorer-16 uses UART2 to connect to the PC.
	// This initialization assumes 36MHz Fpb clock. If it changes,
	// you will have to modify baud rate initializer.
    UARTConfigure(UART2, UART_ENABLE_PINS_TX_RX_ONLY);
    UARTSetFifoMode(UART2, UART_INTERRUPT_ON_TX_NOT_FULL | UART_INTERRUPT_ON_RX_NOT_EMPTY);
    UARTSetLineControl(UART2, UART_DATA_SIZE_8_BITS | UART_PARITY_NONE | UART_STOP_BITS_1);
    UARTSetDataRate(UART2, GetPeripheralClock(), DESIRED_BAUDRATE);
    UARTEnable(UART2, UART_ENABLE_FLAGS(UART_PERIPHERAL | UART_RX | UART_TX));

	// Configure UART2 RX Interrupt
	INTEnable(INT_SOURCE_UART_RX(UART2), INT_ENABLED);
    INTSetVectorPriority(INT_VECTOR_UART(UART2), INT_PRIORITY_LEVEL_2);
    INTSetVectorSubPriority(INT_VECTOR_UART(UART2), INT_SUB_PRIORITY_LEVEL_0);

    // configure for multi-vectored mode
    INTConfigureSystem(INT_SYSTEM_CONFIG_MULT_VECTOR);

    // enable interrupts
    INTEnableInterrupts();


   WriteString("*** UART Interrupt-driven Application Example ***\r\n");
   WriteString("*** Type some characters and observe echo and RA7 LED toggle ***\r\n");


	// Let interrupt handler do the work
	while (1);

	return 0;
}
// helper functions
void WriteString(const char *string)
{
    while(*string != '\0')
    {
        while(!UARTTransmitterIsReady(UART2))
            ;

        UARTSendDataByte(UART2, *string);

        string++;

        while(!UARTTransmissionHasCompleted(UART2))
            ;
    }
}
void PutCharacter(const char character)
{
        while(!UARTTransmitterIsReady(UART2))
            ;

        UARTSendDataByte(UART2, character);


        while(!UARTTransmissionHasCompleted(UART2))
            ;
}
// UART 2 interrupt handler
// it is set at priority level 2
void __ISR(_UART2_VECTOR, ipl2) IntUart2Handler(void)
{
	// Is this an RX interrupt?
	if(INTGetFlag(INT_SOURCE_UART_RX(UART2)))
	{
		// Clear the RX interrupt Flag
	    INTClearFlag(INT_SOURCE_UART_RX(UART2));

		// Echo what we just received.
		PutCharacter(UARTGetDataByte(UART2));


		// Toggle LED to indicate UART activity
		mPORTAToggleBits(BIT_7);

	}

	// We don't care about TX interrupt
	if ( INTGetFlag(INT_SOURCE_UART_TX(UART2)) )
	{
		INTClearFlag(INT_SOURCE_UART_TX(UART2));
	}
}

