lcd driving instructions aren't obvious !

[bhomaidan]

I've 2*16 lcd and I'm totally a beginner so I don't know the instructions to clear the lcd and send some characters. I searched the manual but there's no clear info's about that so please help.

MCU : pic-16f877A

[Ttelmah]

The 'manual' has nothing to do with this....

Driving an LCD, is not a 'compiler' feature.

For an LCD, you need to be using a driver. CCS provide one, for standard text LCD's 'LCD.C'. This is documented _in the file_.

There are also examples of using this, with a keyboard, and a thermomemeter. EX_LCDKB.C, and EX_LCDTH.C.

There is also a 'third party' LCD driver in the code forum FLEX_LCD.C. This can be slightly simpler, and used to be a lot more flexible than the CCS driver (the CCS driver has improved in this regard). I'd suspect many of the long term users here actually use this.

However seriously, you need to also get the data sheet for your LCD. Look particularly at what voltages it requires - particularly the bias voltage Vo.

Best Wishes

[bhomaidan]

Driving an LCD, is not a 'compiler' feature.

I've written the code implemented lcd.c & lcd.h
lcd_init();
lcd_putc("\fReady...\n");

but the output on the lcd was full black first row and empty on the second row !

[temtronic]

Without seeing your code, it sounds like you don't have the LCD connected to the PIC properly.
The LCD driver has default assignments for the LCD module.
Please recheck your wiring it's easy to cross connect a couple of wires,especially if using the same colour wires.
I do know that the 877,LCD driver, LCD modules will together,that's why I suspect a wiring error.

hth
jay

[Ttelmah]

Before going even one step further, have you proved that you are actually able to make the CPU 'work' first?.

Can you attach an LED to one pin of the CPU (with a current limiting resistor), and write a program to flash this. Does the program work, and does the LED flash at the right rate?.

In programming, and electronics, one key thing is to move 'one step at a time'. You need to get the controller working first, before trying to control the LCD.
Once you have this working, and the speed is right, then get the data sheet of the LCD, and triple check your connections. The connections that often give problems, are:
1) Vo.
2) Realising that you connect to D4 to D7 on the LCD, not D0 to D3.
3) Forgetting the ground.

Then realise that if you don't define anything the driver defaults to using the pin connections used in the PicDem board. For your chip it'll be using PORTD. Is this what you have done?. If you want to use your own pin connections, and they don't match these, you need to have a set of defines like:

[bhomaidan]

I tried the microcontroller with the lcd on another compiler (microC Compiler) and the LCD worked very fine. But my problem is in the PICC compiler even though I configured it as posted in the upper reply, so please concentrate on this part.

[Mike Walne]

You're not giving us enough to work on.

I'm assuming the only difference between what works and what doesn't is the compiler. (Same PCB, chip, layout etc.)

CCS compiler requires a very different mindset. (You're not the first to encounter this problem.)

You need to:-

1) Show that you can get an LED flasher to work at the correct rate with CCS.
2) Tell us EXACTLY what all the relevant connections are.
3) Supply the shortest possible complete compilable code which you think should function.
4) Describe what does and doesn't happen.

Mike

[Ttelmah]

I think the key thing is the line:

"I configured it as posted in the upper reply".

This is not what you have to do. You have to change these configurations to match your hardware. These are examples of a set of declarations for an LCD. The set for your hardware, needs to be for your hardware, and nobody else can see this.