LCD Driver

doggitz · Joined: 04 Sep 2011 Posts: 9

A newbie needs some help. I am using an 18F4620 with a PCWH compiler and a PICKIT2 programmer. I am very new to C but have a reasonable amount of experience with BASIC. I have been using the WIZARD in the CCS IDE and find it very helpful for getting started. After compiling my program, I use the PICKIT2 software to import the hex file and program the chip. I have tried a few led flashing programs and it seems to work perfectly.

I can't get the lcd.c to work. My pin connections are:
Enable D5
RS D4
Data4 D0
Data5 D1
Data6 D2
Data7 D3

I am using the wizard to set the pins and when I look at the #define statements they are set correctly. I am using a 10MHz crystals and have set this, also in the wizard. As part of the program, I am flashing an LED, so I know my chip programming steps are working. I have used my BASIC compiler to test the board and the lcd, and it works properly.

Here is my program

temtronic · Posted: Sun Sep 04, 2011 9:58 am

While I don't use that PIC or lcd driver...

... the first thing is that you've got a fuse set for LP option(<200KHz) yet the #use delay(clock=10,000,000) //my commas
and you say you're using a 10MHz xtal.....
So I'd select the correct fuse for that xtal....

I use the flex_lcd driver with no problems...so perhaps maybe you haven't enabled/disabled the RW line or enable LCD control line ??

doggitz · Joined: 04 Sep 2011 Posts: 9

Thanks for the thought

Tried commenting out the LP line - no effect
I have also tried the flex_lcd driver and get the same result

I look at the comment section for the flex_lcd driver and find comments about grounding the RW line. I'm not sure whether that line on my board is grounded (I know that it is NOT connected to the chip) but will check it. As I mentioned, I tried a little test program using Proton Basic with the exact same set up on my test board, and the display works perfectly.

-D

temtronic · Posted: Sun Sep 04, 2011 12:17 pm

Your LCD to PIC wiring is wrong...

According to the LCD.c driver..
// As defined in the following structure the pin connection is as follows:
// D0 enable
// D1 rs
// D2 rw
// D4 D4
// D5 D5
// D6 D6
// D7 D7

you've got..

Enable D5
RS D4
Data4 D0
Data5 D1
Data6 D2
Data7 D3

So..
you either have to rewire the connections to be compatible with the LCD.c driver

OR
recode the driver to conform to your pinout

OR
use the flex_lcd driver and configure it to be 'pin compatible' with how you want the connections to be made.This is what I do, far easier and simpler.

Any of the above options will work, it all depends on how you want to 'configure' the system.

doggitz · Joined: 04 Sep 2011 Posts: 9

OK thanks --

I'll look at the flex driver and see how that works.

keep you posted

doggitz · Joined: 04 Sep 2011 Posts: 9

I have studied the flex_lcd driver documentation. It looks like the pin declarations are made in the driver - which I did. I also commented out the RW portion - which I am not using. I also included the stdio driver and made sure that my crystal was set to HS for a 10 MHZ crystal. No luck. All I get is a single (top) row of 5X8 pixel blocks. I also used an ohm meter to be sure all of the connections between the pic and the lcd were correct. any other suggestions?