2020. 3. 1. 10:44ㆍ카테고리 없음
In this project, we will have brief discussion on how to interface 16×2 LCD module to AT89C51, which is an 8051 family microcontroller. We use LCD display for the displaying messages in a more interactive way to operate the system or displaying error messages etc. Interfacing 16×2 LCD with 8051 microcontroller is very easy if you understanding the working of LCD.Hence, in this project, I will not only give the information of LCD and also provide the code in C language which is working fine without any errors. Table of Contents.A Brief Note on 16×2 LCD16×2 Liquid Crystal Display which will display the 32 characters at a time in two rows (16 characters in one row). Each character in the display is of size 5×7 pixel matrix. This matrix differs for different 16×2 LCD modules, if you take JHD162A, this matrix goes to 5×8.
There are 16 pins in the LCD module, the pin configuration us given belowPIN NONAMEFUNCTION1VSSGround pin2VCCPower supply pin of 5V3VEEUsed for adjusting the contrast commonly attached to the potentiometer.4RSRS is the register select pin used to write display data to the LCD (characters), this pin has to be high when writing the data to the LCD. During the initializing sequence and other commands this pin should low.5R/WReading and writing data to the LCD for reading the data R/W pin should be high (R/W=1) to write the data to LCD R/W pin should be low (R/W=0)6EEnable pin is for starting or enabling the module. A high to low pulse of about 450ns pulse is given to this pin.7DB08DB19DB210DB311DB4DB0-DB7 Data pins for giving data(normal data like numbers characters or command data) which is meant to be displayed12DB513DB614DB715LED+Back light of the LCD which should be connected to Vcc16LED-Back light of LCD which should be connected to ground.So by reading the above table you can get a brief idea how to display a character. For displaying a character you should enable the enable pin (pin 6) by giving a pulse of 450ns, after enabling the pin6 you should select the register select pin (pin4) in write mode.
C Program For Lcd Interfacing With At89s52 Screen
Lcd Interfacing With 8051 Pdf
To select the register select pin in write mode you have to make this pin high (RS=1), after selecting the register select you have to configure the R/W to write mode that is R/W should be low (R/W=0). Follow these simple steps for displaying a character or data. E=1; enable pin should be high. RS=1; Register select should be high.
Lcd Interfacing With 8051 Notes
R/W=0; Read/Write pin should be low.To send a command to the LCD just follows these steps:. E=1; enable pin should be high. RS=0; Register select should be low. R/W=0; Read/Write pin should be low.Commands: There are some preset commands which will do a specific task in the LCD. These commands are very important for displaying data in LCD.
Below is a simple code written in assembly using keil.The code displays HELLO.The code is written for 8051 uc. For info on pin connections or other things,email me-ORG 0000HHERE: MOV A,#38HACALL CMNDMOV A,#0FHACALL CMNDMOV A,#06HACALL CMNDMOV A,#01HACALL CMNDMOV A,#080HACALL CMNDMOV A,#’ ‘ACALL DISPMOV A,#’H’ACALL DISPMOV A,#’E’ACALL DISPMOV A,#’L’ACALL DISPMOV A,#’ L’ACALL DISPMOV A,#’O’ACALL DISPSJMP HERECMND: MOV P2,ACLR P3.5CLR P3.4SETB P3.3CLR P3.3RETDISP: MOV P2,ASETB P3.5CLR P3.4CLR P3.3SETB P3.3RETEND.