lcd initializing problem with 89v51rd2

[princepatel9]

i am trying to connect lcd in 4bit mode with p0.0top0.3 data line and p0.5 and p0.7 rs and en line with rw gnd. but when i am switching on the circuit , in my lcd display only one 1 line with black blocks is coming only. after progrmming also only block line gets displayed. i also checked my lcd, it is perfectly working. so, please tell me anyone the solution for this problem. and also please send me the sample pgm with this pin out and also the circuit diagram.

 

[mgate]

If you are using an Hitachi HD44780 standard compatible LCD, You might want to check this tutorial:
https://www.8051projects.net/lcd-interfacing/introduction.php

here is the LCD connection diagram for 4 bit mode, and some how to tips:
https://www.8051projects.net/lcd-interfacing/lcd-4-bit.php

and here is some C and ASM code:
https://www.8051projects.net/lcd-interfacing/lcd-4-bit-programming.php



some additional tips:
-the lcd controller will increment/decrement(inc. or dec. is setup defined) char position after each char write.
-to write a character at a specific location, you need to specify the memory location before write char data..
-to write to the second line you need to set memory location to the begin of second line..

If you google for HD44780 interfacing 8051, you will get lot's of source code... try searching in this forum to0 ( as it is a common thread subject)

i.e. : https://www.edaboard.com/threads/214712/