Using Graphical LCD with PIC16F877A

[PICTRAIL]

Hi, I bought Graphic LCD but i'm having problem using it with PIC16F877A. I tried to modify sample source program from PR21 Kit but it doesn't work.
I need someone to help me with a sample source code just to write "Cytron Technology" on the GLCD.

Thanks.

[hyng]

I'm not so sure. But i think the clue is at

CODE: SELECT_ALL_CODE

char test[] = {"testing0"};
char cali [] = {"  CALIBRATE...  "};
char mssg1[] = {"  LET IT FLAT "};
char mssg2[] = {" AND PRESS SW1 "};
char mssg3[] = {"FREESPACE      "};
char mssg4[] = {"FRICTION       "};

have you try to modify them?

[ABSF]

Hi, I bought Graphic LCD but i'm having problem using it with PIC16F877A. I tried to modify sample source program from PR21 Kit but it doesn't work.
I need someone to help me with a sample source code just to write "Cytron Technology" on the GLCD.

You didn't give enough details of the GLCD that you've bought. Which controller chip was it based on: HD61202, KS0108, T6963C, SED1330 or ST7920? What is the size of your GLCD? What clock rate is your 16F877a running on?

The PR21 GLCD is based on ST7920 and the 18F452 is running at 10MHz. That means the instruction cycle is 400nS per instruction. If your 16F877A is running at 20MHz, it is twice faster than the PR21 MCU.

I have a GLCD based on KS0108B chip and the connections are different from that of the PR21's GLCD. On P18, P16 & P15 of my GLCD, I have VEE , CS2 & CS1 respectively. My GLCD came with a demo board with a 16F57 PIC on it, so I have no problem testing my LCD that it is working by just pluging in the USB plug to supply +5V it requires.

Allen

[ABSF]

Hi,

Can someone confirm whether there is a character ROM built in the GLCD like the 16X2 LCD. Or do I have to load the whole ASCII charactet pattern into my program?

Allen

[PICTRAIL]

The GLCD is 128 x 64 same one with the PR21 Kit. Likewise my PIC16F877A is running on 20MHz.
I am very new to PIC microcontroller and i can't seem to get a way out to modify the other program.

I would appreciate a sample program just to write any message like (CYTRON TECHNOLOGY) placed at the centre of the screen and a sample image loading. With this i can make adjustment for it to suit my application.

Thanks for your support.


Ebby.

[hyng]

The GLCD is 128 x 64 same one with the PR21 Kit. Likewise my PIC16F877A is running on 20MHz.
I am very new to PIC microcontroller and i can't seem to get a way out to modify the other program.

I would appreciate a sample program just to write any message like (CYTRON TECHNOLOGY) placed at the centre of the screen and a sample image loading. With this i can make adjustment for it to suit my application.

Thanks for your support.


Ebby.

Please try with what i suggested

[PICTRAIL]

Hi, i did try but yet it does'nt work...

[ABSF]

You mean you're not getting anything on the LCD? How did you connect the Backlight? In PR21, the backlight goes to a transistor and is software controlled. The contrast should also be set to medium level.

The 3 arrays of 1024 bytes each are the "Cytron logo" and "GAME OVER" in graphic mode. I have not yet decode the 3rd one. The "icon" is a ball shaped graphic. To display text, it seems you just need the functions: init, delay, send_config, send_char, lcd_goto, lcd_clr, & send_string. To display graphic you need: lcd_xy, d_graphic, & clr_graphic.

But I still think that there is something wrong with your hardware setup.

Best regards,

Allen

[PICTRAIL]

Thank you so much for the suggestion... The backlight is ok because i'm controlling it manually using potentiometer.
I think the problem with PR21 sample is that it's using PIC18 while i am trying to use PIC16F877A i think there is difference in the protocol.

[shiyan]

Thank you so much for the suggestion... The backlight is ok because i'm controlling it manually using potentiometer.
I think the problem with PR21 sample is that it's using PIC18 while i am trying to use PIC16F877A i think there is difference in the protocol.

I don think you mean protocol. Protocol mean the method to communicate between 2 nodes or software layers.

Yes, definitely C18 and C compiler for PIC16F is different, but I don think is the protocol. Maybe we can study what is being done in those functions such as initialize, sending graphic to LCD.

Speed might also affect, do check the DIY project by Cytron, PIC18F can use PLL to multiplier the external oscillator to 4 times.