I am interfacing Lcd to msp430f2132.Lcd display facing problem with garbage value.what changes should i do in this code.please help me.
#include "msp430f2132.h"unsigned int i;#define LCM_DIR P1DIR#define LCM_OUT P1OUT//// Define symbolic LCM - MCU pin mappings// We've set DATA PIN TO 4,5,6,7 for easy translation//#define LCM_PIN_RS BIT5 // p2.5#define LCM_PIN_EN BIT6 // P2.6#define LCM_PIN_D7 BIT7 // P1.7#define LCM_PIN_D6 BIT6 // P1.6#define LCM_PIN_D5 BIT5 // P1.5#define LCM_PIN_D4 BIT4 // P1.4#define LCM_PIN_MASK ((LCM_PIN_RS | LCM_PIN_EN | LCM_PIN_D7 | LCM_PIN_D6 | LCM_PIN_D5 | LCM_PIN_D4))#define FALSE 0#define TRUE 1//// 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(200); // // pull EN bit high // LCM_OUT |= LCM_PIN_EN; __delay_cycles(200); // // pull EN bit low again // LCM_OUT &= (~LCM_PIN_EN); __delay_cycles(200);}//// 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 & 0xF0); 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 P1.7 - P1.4 // using a simple assignment // LCM_OUT &= (~LCM_PIN_MASK); LCM_OUT |= ((ByteToSend & 0x0F) << 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(1000000); // // initialize the LCM module // // 1. Set 4-bit input // LCM_OUT &= ~LCM_PIN_RS; __delay_cycles(5000); LCM_OUT &= ~LCM_PIN_EN; __delay_cycles(5000); LCM_OUT = 0x20; __delay_cycles(5000); PulseLcm(); __delay_cycles(5000); // // set 4-bit input - second time. // (as reqd by the spec.) // SendByte(0x28, FALSE); __delay_cycles(5000); // // 2. Display on, cursor on, blink cursor // SendByte(0x0E, FALSE); __delay_cycles(5000); // // 3. Cursor move auto-increment // SendByte(0x06, FALSE); __delay_cycles(5000);}//// 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); __delay_cycles(5000); c++; }}//// Routine Desc//// main entry point to the sketch//// Parameters// // void.//// Returns// // void.//void main(void){ WDTCTL = WDTPW + WDTHOLD; // Stop watchdog timer DCOCTL=CAL_DCO_1MHZ ; BCSCTL1=CAL_BC1_1MHZ ; P2DIR |=0xA0; P2OUT|=0xA0; for(;;) { InitializeLcm(); ClearLcmScreen(); PrintStr("H!"); i = 50000; // Delay do (i--); while (i != 0);}}
haridini belanfacing problem with garbage value.what changes should i do in this code.please help me.
Before you jump in and start changing stuff, you need to work out why you are getting "garbage".
This is called debugging - and is an essential part of any form of development.
Once you know out why you are getting "garbage", it should be clear what you need to change in order to correct the problem(s)!
If you just make random changes whithout knowing why you are getting "garbage", you will not know if you have actually fixed the underlying problem(s) - or just masked the symptoms...
So, the first thing you need to check is that your code actually produces signals to the LCD that are fully in conformance with the LCD's specifications. You should pay particular attention to timing...
Here's some debugging tips to get you started:
http://www.8052.com/faqs/120313
http://www.eetimes.com/discussion/break-point/4027526/Developing-a-good-bedside-manner?pageNumber=0
thank you