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//###########################################################################
// FILE: Example_2837xSSci_Echoback.c
// TITLE: SCI Echoback.
//
//! \addtogroup cpu01_example_list
//! <h1>SCI Echoback (sci_echoback)</h1>
//!
//! This test receives and echo-backs data through the SCI-A port.
//!
//! The PC application 'hyperterminal' or another terminal
//! such as 'putty' can be used to view the data from the SCI and
//! to send information to the SCI. Characters received
//! by the SCI port are sent back to the host.
//!
//! \b Running \b the \b Application
//! -# Configure hyperterminal or another terminal such as putty:
//!
//! For hyperterminal you can use the included hyperterminal configuration file SCI_96.ht.
//! To load this configuration in hyperterminal
//! -# Open hyperterminal
//! -# Go to file->open
//! -# Browse to the location of the project and
//! select the SCI_96.ht file.
//! -# Check the COM port.
//! The configuration file is currently setup for COM1.
//! If this is not correct, disconnect (Call->Disconnect)
//! Open the File-Properties dialogue and select the correct COM port.
//! -# Connect hyperterminal Call->Call
//! and then start the 2837xS SCI echoback program execution.
//! -# The program will print out a greeting and then ask you to
//! enter a character which it will echo back to hyperterminal.
//!
//! \note If you are unable to open the .ht file, or you are using
//! a different terminal, you can open a COM port with the following settings
//! - Find correct COM port
//! - Bits per second = 9600
//! - Date Bits = 8
//! - Parity = None
//! - Stop Bits = 1
//! - Hardware Control = None
//!
//! \b Watch \b Variables \n
//! - LoopCount - the number of characters sent
//!
//! \b External \b Connections \n
//! Connect the SCI-A port to a PC via a transceiver and cable.
//! - GPIO28 is SCI_A-RXD (Connect to Pin3, PC-TX, of serial DB9 cable)
//! - GPIO29 is SCI_A-TXD (Connect to Pin2, PC-RX, of serial DB9 cable)
//
//###########################################################################
// $TI Release: F2837xS Support Library v180 $
// $Release Date: Fri Nov 6 16:27:58 CST 2015 $
// $Copyright: Copyright (C) 2014-2015 Texas Instruments Incorporated -
// http://www.ti.com/ ALL RIGHTS RESERVED $
//###########################################################################
#include "F28x_Project.h" // Device Headerfile and Examples Include File
// Prototype statements for functions found within this file.
void scib_echoback_init(void);
void scib_fifo_init(void);
void scib_xmit(int a);
void scib_msg(char *msg);
// Global counts used in this example
Uint16 LoopCount;
void main(void)
{
Uint16 ReceivedChar;
char *msg;
// Step 1. Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the F2837xS_SysCtrl.c file.
InitSysCtrl();
// Step 2. Initialize GPIO:
// This example function is found in the F2837xS_Gpio.c file and
// illustrates how to set the GPIO to it's default state.
InitGpio();
// For this example, only init the pins for the SCI-B port.
EALLOW;
GpioCtrlRegs.GPCMUX2.bit.GPIO86 = 1;
GpioCtrlRegs.GPCMUX2.bit.GPIO87 = 1;
GpioCtrlRegs.GPCGMUX2.bit.GPIO86 = 1;
GpioCtrlRegs.GPCGMUX2.bit.GPIO87 = 1;
EDIS;
// Step 3. Clear all __interrupts and initialize PIE vector table:
// Disable CPU __interrupts
DINT;
// Initialize PIE control registers to their default state.
// The default state is all PIE __interrupts disabled and flags
// are cleared.
// This function is found in the F2837xS_PieCtrl.c file.
InitPieCtrl();
// Disable CPU __interrupts and clear all CPU __interrupt flags:
IER = 0x0000;
IFR = 0x0000;
// Initialize the PIE vector table with pointers to the shell Interrupt
// Service Routines (ISR).
// This will populate the entire table, even if the __interrupt
// is not used in this example. This is useful for debug purposes.
// The shell ISR routines are found in F2837xS_DefaultIsr.c.
// This function is found in F2837xS_PieVect.c.
InitPieVectTable();
// Step 4. User specific code:
LoopCount = 0;
scib_fifo_init(); // Initialize the SCI FIFO
scib_echoback_init(); // Initialize SCI for echoback
DELAY_US(3000000); // 3SEC wait
msg = "\r\n\n\nHello World!\0";
scib_msg(msg);
msg = "\r\nYou will enter a character, and the DSP will echo it back! \n\0";
scib_msg(msg);
for(;;)
{
msg = "\r\nEnter a character: \0";
scib_msg(msg);
// Wait for inc character
while(ScibRegs.SCIFFRX.bit.RXFFST == 0) { } // wait for XRDY =1 for empty state
// Get character
ReceivedChar = ScibRegs.SCIRXBUF.all;
// Echo character back
msg = " You sent: \0";
scib_msg(msg);
scib_xmit(ReceivedChar);
LoopCount++;
}
}
// Test 1,SCIC DLB, 8-bit word, baud rate 0x000F, default, 1 STOP bit, no parity
void scib_echoback_init()
{
// Note: Clocks were turned on to the SCIC peripheral
// in the InitSysCtrl() function
ScibRegs.SCICCR.all =0x0007; // 1 stop bit, No loopback
// No parity,8 char bits,
// async mode, idle-line protocol
ScibRegs.SCICTL1.all =0x0003; // enable TX, RX, internal SCICLK,
// Disable RX ERR, SLEEP, TXWAKE
//ScibRegs.SCICTL2.all =0x0003;
ScibRegs.SCICTL2.bit.TXINTENA =1;
ScibRegs.SCICTL2.bit.RXBKINTENA =1;
//
// SCIC at115200 baud
ScibRegs.SCIHBAUD.all = 0x0;
ScibRegs.SCILBAUD.all = 53;
ScibRegs.SCICTL1.all =0x0023; // Relinquish SCI from Reset
}
// Transmit a character from the SCI
void scib_xmit(int a)
{
while (ScibRegs.SCIFFTX.bit.TXFFST != 0) {}
ScibRegs.SCITXBUF.all =a;
}
void scib_msg(char * msg)
{
int i;
i = 0;
while(msg[i] != '\0')
{
scib_xmit(msg[i]);
i++;
}
}
// Initialize the SCI FIFO
void scib_fifo_init()
{
ScibRegs.SCIFFTX.all=0xE040;
ScibRegs.SCIFFRX.all=0x2044;
ScibRegs.SCIFFCT.all=0x0;
}
//===========================================================================
// No more.
//===========================================================================
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