LCD problem with 16F628

[Melanie]

You might want to try these two things...

1. Ground D0-D3 on the LCD

Don't leave those lines not connected and floating - it's bad practice.

2. Increase the inital Pause 500 to Pause 1000

Pause 500 may be insufficient for your LCD to initialise at power-on.

Why don't you want to use A.5 for E-Bit? That way the whole of PORTB is free for your applications use. If you used A.6 for the RS Bit, you wouldn't need that Resistor either.

Additionally, although this has nothing to do with the LCD... INTCON = 0 is unnescessary as Interrupts are disabled by default.

[ngeronikolos]

Melanie,

Thanks for your advice but nothing.I ground D0-D3 on the LCD and I change the inital Pause to 1000 and 1500.

I saw on my lcd all first line with black blocks.

Please advice

[Melanie]

1. Check the SPELLING of your LCD Defines... they must be EXACT because the compiler will not flag errors if have made a mistake there.

2. Check that you have not mistakenly swapped your E or RS bits and connected them the wrong way around...

3. Turn down your contrast... if it's too high then you might be swamping any displayed data with black blocks.

4. Finally, double-check your hardware connections against your DEFINES.

There are no problems or issues connecting LCDs to a 16F628 on internal oscillator with internal MCLR therefore it must be something in your connection...

[ngeronikolos]

The compiler is OK.No errors.

May my programmer cause the problem?
Because the circuit and the program was working in the past.

Thanks

[ngeronikolos]

Melanie,

I check my circuit and it seems ok.
That is the diargam of it.

Please have a look.

[Melanie]

Well, let's make sure your PIC is working...

Got an LED? Connect it say between PortB.0 with a series Resistor (anything between 220R and 470R) and Vss (0v).

After your LCD define put...

LED var PORTB.0

In your main loop, anywhere put...

Toggle LED

When the PIC runs, your LED should blink...

[ngeronikolos]

Dear Melanie,

You are right. My PIC is not working but I can not understand why?
I try to blink a led but nothing.Where is the problem with my code?

I attach my code and the hex file.

PLEASE HELP MEEEEEEEEEEEEEEEEEEEEEEE.