16x2 lcd interfacing with msp430g2553

suri naidu

Other Parts Discussed in Thread: MSP430G2553

HI,

Iam using msp430g2553 and below code is using but no string should be displayed

can any help what i mistake

//
// MSP430 LCD interface
//
// | LCM |
// LCM Pin # | Function | MSP Pin #
//----------------------------
// PIN 5 | RW | GND
// PIN 4 | RS | P2.1
// PIN 6 | EN | P2.0
// PIN 14 | DB7 | P2.5
// PIN 13 | DB6 | P2.4
// PIN 12 | DB5 | P2.3
// PIN 11 | DB4 | P2.2
//

/*
The other LCM pins connections are as follows:

*/

//
// MSP430 LCD Code
//

#include "msp430G2553.h"

#define LCM_DIR P2DIR
#define LCM_OUT P2OUT

//
// Define symbolic LCM - MCU pin mappings
// We've set DATA PIN TO 4,5,6,7 for easy translation
//
#define LCM_PIN_RS BIT1 // P2.1
#define LCM_PIN_EN BIT0 // P2.0
#define LCM_PIN_D7 BIT5 // P2.5
#define LCM_PIN_D6 BIT4 // P2.4
#define LCM_PIN_D5 BIT3 // P2.3
#define LCM_PIN_D4 BIT2 // P2.2

#define FALSE 0
#define TRUE 1
void __delay_cycles(unsigned long i)
{
for(;i>0;i--)
{

}
}
//
// Routine Desc:
//
// This is the function that must be called
// whenever the LCM needs to be told to
// scan it's data bus.
//
// Parameters:
//
// void.
//
// Return
//
// void.
//
void PulseLcm()
{
//
// pull EN bit low
//
LCM_OUT &= ~LCM_PIN_EN;
__delay_cycles(600);

//
// pull EN bit high
//
LCM_OUT |= LCM_PIN_EN;
__delay_cycles(600);

//
// pull EN bit low again
//
LCM_OUT &= (~LCM_PIN_EN);
__delay_cycles(600);
}

//
// Routine Desc:
//
// Send a byte on the data bus in the 4 bit mode
// This requires sending the data in two chunks.
// The high nibble first and then the low nible
//
// Parameters:
//
// ByteToSend - the single byte to send
//
// IsData - set to TRUE if the byte is character data
// FALSE if its a command
//
// Return
//
// void.
//
void SendByte(char ByteToSend, int IsData)
{
//
// clear out all pins
//
LCM_OUT &= (~LCM_PIN_MASK);
//
// set High Nibble (HN) -
// usefulness of the identity mapping
// apparent here. We can set the
// DB7 - DB4 just by setting P1.7 - P1.4
// using a simple assignment
//
LCM_OUT |= (ByteToSend & 0x0F);

if (IsData == TRUE)
{
LCM_OUT |= LCM_PIN_RS;
}
else
{
LCM_OUT &= ~LCM_PIN_RS;
}

//
// we've set up the input voltages to the LCM.
// Now tell it to read them.
//
PulseLcm();
//
// set Low Nibble (LN) -
// usefulness of the identity mapping
// apparent here. We can set the
// DB7 - DB4 just by setting P2.7 - P2.4
// using a simple assignment
//
LCM_OUT &= (~LCM_PIN_MASK);
LCM_OUT |= ((ByteToSend & 0xF0) << 4);

if (IsData == TRUE)
{
LCM_OUT |= LCM_PIN_RS;
}
else
{
LCM_OUT &= ~LCM_PIN_RS;
}

//
// we've set up the input voltages to the LCM.
// Now tell it to read them.
//
PulseLcm();
}

//
// Routine Desc:
//
// Set the position of the cursor on the screen
//
// Parameters:
//
// Row - zero based row number
//
// Col - zero based col number
//
// Return
//
// void.
//
void LcmSetCursorPosition(char Row, char Col)
{
char address;

//
// construct address from (Row, Col) pair
//
if (Row == 0)
{
address = 0;
}
else
{
address = 0x40;
}

address |= Col;

SendByte(0x80 | address, FALSE);
}

//
// Routine Desc:
//
// Clear the screen data and return the
// cursor to home position
//
// Parameters:
//
// void.
//
// Return
//
// void.
//
void ClearLcmScreen()
{
//
// Clear display, return home
//
SendByte(0x01, FALSE);
SendByte(0x02, FALSE);
}

//
// Routine Desc:
//
// Initialize the LCM after power-up.
//
// Note: This routine must not be called twice on the
// LCM. This is not so uncommon when the power
// for the MCU and LCM are separate.
//
// Parameters:
//
// void.
//
// Return
//
// void.
//
void InitializeLcm(void)
{
//
// set the MSP pin configurations
// and bring them to low
//
LCM_DIR |= LCM_PIN_MASK;
LCM_OUT &= ~(LCM_PIN_MASK);

//
// wait for the LCM to warm up and reach
// active regions. Remember MSPs can power
// up much faster than the LCM.
//
__delay_cycles(600000);

//
// initialize the LCM module
//
// 1. Set 4-bit input
//
LCM_OUT &= ~LCM_PIN_RS;
LCM_OUT &= ~LCM_PIN_EN;

LCM_OUT = 0x20;
PulseLcm();

//
// set 4-bit input - second time.
// (as reqd by the spec.)
//
SendByte(0x28, FALSE);

//
// 2. Display on, cursor on, blink cursor
//
//SendByte(0x0E, FALSE);
SendByte(0xC0, FALSE);

//
// 3. Cursor move auto-increment
//
SendByte(0x06, FALSE);
SendByte(0x01, FALSE);
}

//
// Routine Desc
//
// Print a string of characters to the screen
//
// Parameters:
//
// Text - null terminated string of chars
//
// Returns
//
// void.
//
void PrintStr(char *Text)
{
char *c;

c = Text;

while ((c != 0) && (*c != 0))
{
SendByte(*c, TRUE);
c++;
}
}

//
// Routine Desc
//
// main entry point to the sketch
//
// Parameters
//
// void.
//
// Returns
//
// void.
//
void main(void)
{
WDTCTL = WDTPW + WDTHOLD; // Stop watchdog timer

InitializeLcm();

ClearLcmScreen();

PrintStr("Hello HANBIT!");

while (1)
{
__delay_cycles(6000);
}

}

over 13 years ago