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//########################################################################### 
// 
// FILE:    Example_281xSci_FFDLB.c 
// 
// TITLE:   DSP281x Device SCI FIFO Digital Loop Back Test.  
// 
// ASSUMPTIONS: 
// 
//          This program requires the DSP281x V1.00 header files.   
//          As supplied, this project is configured for "boot to H0" operation. 
// 
//          Other then boot mode pin configuration, no other hardware configuration 
//          is required.  
// 
// DESCRIPTION: 
// 
//          This test uses the loopback test mode of the SCI module to send 
//          characters starting with 0x00 through 0xFF.  The test will send 
//          a character and then check the receive buffer for a correct match. 
// 
//          Watch Variables: 
//                LoopCount for the number of characters sent 
//                ErrorCount  
//		 
// 
//########################################################################### 
// 
// Original Author: S.S. 
// 
//  Ver | dd mmm yyyy | Who  | Description of changes 
// =====|=============|======|=============================================== 
//  1.00| 11 Sep 2003 | L.H. | No change since previous version (v.58 Alpha) 
//########################################################################### 
 
 
#include "DSP281x_Device.h" 
#include "DSP281x_Examples.h" 
 
// Prototype statements for functions found within this file. 
void scia_loopback_init(void); 
void scia_fifo_init(void);	 
void scia_xmit(int a); 
void error(int); 
interrupt void scia_rx_isr(void); 
interrupt void scia_tx_isr(void); 
 
// Global counts used in this example 
Uint16 LoopCount; 
Uint16 ErrorCount;  
 
void main(void) 
{ 
    Uint16 SendChar; 
    Uint16 ReceivedChar; 
     
// Step 1. Initialize System Control registers, PLL, WatchDog, Clocks to default state: 
        // This function is found in the DSP281x_SysCtrl.c file. 
	InitSysCtrl(); 
 
// Step 2. Select GPIO for the device or for the specific application: 
       // This function is found in the DSP281x_Gpio.c file. 
       // InitGpio(); skip this as this is example selects the I/O for SCI in this file itself 
    EALLOW; 
    GpioMuxRegs.GPFMUX.all=0x0030;	// Select GPIOs to be Sci pins	  
                                    // Port F MUX - x000 0000 0011 0000 
    EDIS; 
 
// Step 3. Initialize PIE vector table: 
      // The PIE vector table is initialized with pointers to shell Interrupt  
      // Service Routines (ISR).  The shell routines are found in DSP281x_DefaultIsr.c. 
      // Insert user specific ISR code in the appropriate shell ISR routine in  
      // the DSP28_DefaultIsr.c file. 
 
      // Disable and clear all CPU interrupts: 
	DINT; 
	IER = 0x0000; 
	IFR = 0x0000; 
 
      // Initialize Pie Control Registers To Default State: 
      // This function is found in the DSP281x_PieCtrl.c file. 
	  // InitPieCtrl();  PIE is not used for this example 
 
      // Initialize the PIE Vector Table To a Known State: 
      // This function is found in DSP281x_PieVect.c. 
      // This function populates the PIE vector table with pointers 
      // to the shell ISR functions found in DSP281x_DefaultIsr.c. 
	  InitPieVectTable();   
 
      // Enable CPU and PIE interrupts 
      // This example function is found in the DSP281x_PieCtrl.c file.    
      EnableInterrupts(); 
	 
// Step 4. Initialize all the Device Peripherals to a known state: 
      // This function is found in DSP281x_InitPeripherals.c 
      // InitPeripherals(); skip this for SCI tests 
	 
// Step 5. User specific functions, Reassign vectors (optional), Enable Interrupts: 
 
    LoopCount = 0; 
    ErrorCount = 0; 
     
    scia_fifo_init();	   // Initialize the SCI FIFO 
    scia_loopback_init();  // Initalize SCI for digital loop back  
 
    // Note: Autobaud lock is not required for this example 
     
    // Send a character starting with 0  
    SendChar = 0;								 
 
// Step 6. Send Characters forever starting with 0x00 and going through 
// 0xFF.  After sending each, check the recieve buffer for the correct value 
 
	for(;;) 
    {  
       scia_xmit(SendChar); 
       while(SciaRegs.SCIFFRX.bit.RXFIFST !=1) { } // wait for XRDY =1 for empty state 
   
       // Check received character 
       ReceivedChar = SciaRegs.SCIRXBUF.all;			 
       if(ReceivedChar != SendChar) error(1); 
 
       // Move to the next character and repeat the test 
       SendChar++; 
       // Limit the character to 8-bits 
       SendChar &= 0x00FF; 
       LoopCount++; 
    } 
 
} 	 
 
 
// Step 7. Insert all local Interrupt Service Routines (ISRs) and functions here:	 
 
void error(int ErrorFlag) 
{ 
      ErrorCount++; 
//    asm("     ESTOP0");  // Uncomment to stop the test here 
//    for (;;); 
 
} 
 
// Test 1,SCIA  DLB, 8-bit word, baud rate 0x000F, default, 1 STOP bit, no parity  
void scia_loopback_init() 
{     
    // Note: Clocks were turned on to the SCIA peripheral 
    // in the InitSysCtrl() function 
     
 	SciaRegs.SCICCR.all =0x0007;   // 1 stop bit,  No loopback  
                                   // No parity,8 char bits, 
                                   // async mode, idle-line protocol 
	SciaRegs.SCICTL1.all =0x0003;  // enable TX, RX, internal SCICLK,  
                                   // Disable RX ERR, SLEEP, TXWAKE 
	SciaRegs.SCICTL2.all =0x0003;  
	SciaRegs.SCICTL2.bit.TXINTENA =1; 
	SciaRegs.SCICTL2.bit.RXBKINTENA =1; 
    SciaRegs.SCIHBAUD    =0x0000; 
    SciaRegs.SCILBAUD    =0x000F; 
	SciaRegs.SCICCR.bit.LOOPBKENA =1; // Enable loop back   
	SciaRegs.SCICTL1.all =0x0023;     // Relinquish SCI from Reset  
} 
 
// Transmit a character from the SCI' 
void scia_xmit(int a) 
{ 
    SciaRegs.SCITXBUF=a; 
}     
 
// Initalize the SCI FIFO 
void scia_fifo_init()										 
{ 
    SciaRegs.SCIFFTX.all=0xE040; 
    SciaRegs.SCIFFRX.all=0x204f; 
    SciaRegs.SCIFFCT.all=0x0; 
     
}   
 
                							 
  
     
 
 
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// No more. 
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