i am doing a project which needs to control the text LCD with AT89S52. i got scuuess in initializing the LCD by connecting the 8 data pin to port 0 without using external pull-up resistor. However, when i try to connect to port 1 instead and make appropritate changes in programme, it can;t work.
Try using the resistor bank for pull up.It usually works.U need to use the pull ups wherever mentioned fror the controller.
read the datasheet of the lcd and give proper signals for initialising the Lcd.
If u want i may send u the code for lcd for 89c51.
Also check the voltage levels of the LCD and Controller....Sometimes the unwanted voltage drops occur which can cause reduced supply voltages for the circuit..
in fact i got the c code for the interfacing of LCD and MCU. i still have questions about....
1. For AT89S52, other than port 0, port 1, 2 and 3 are internally pulled-up. i just wonder why i still need to add an external pull-up resistor for port 1....
2. is it possible to connect the data port to other port pins than port 0 for the interfacing of LCD?