EB-005-12-3 and PIC18F26K80 with DEM20486SYH-LY LCD Problems

[victorhantelmann]

I can't figure out how to make this work ... I am using PIC18F26K80 for it's CAN capabilities because I will also need to be able to see what will be sent or received by CAN (future development).
The problem is that for the moment I can't make the LCD type DEM20486SYH-LY to work by using Flowcode 5 LCD component functions... Can you please point me what am I doing wrong?
There shouldn't any problem since DEM20486SYH-LY is Samsung's KS0066U DRIVER & CONTROLLER based as your EB005 LCD Board but in fact there is (probably something that I' doing wrong...)
Thank you in advance.

[victorhantelmann]

I am also adding a link to KS0066U datasheet
http://www.ece.uidaho.edu/ee/classes/EC ... S0066U.pdf
and DEM20486SYH datasheet for reference information.

[dazz]

Hi
what issues are you having ie nothing displaying etc
Regards
Dazz

[Enamul]

Hi
You have to check two things..One is whether your LCD controller is HD44780 or compatible with that or not. If not you have to modify the c code to make it compatible. Your R/W pin of LCD need to be ground for normal LCD operations. I am not sure whether you have done that in program or not..better to GND in hardware before you are sure that it works fine with existing LCD component of Flowcode.

[medelec35]

Hi Victor,
I can spot two issues with your flowchart.
1) You have set the osc frequency to 40MHz.
the default internal osc with no osccon set is 8MHz.
Therefore with PLL = 4 x 8 = 32MHz

2)Watchdog is enabled and there are no clear watchdog commands or auto clear watchdog is not enabled.

Is the LED running at the precise 1Hz?

Can you try this version please. I can't guarantee without testing it first.
Unfortunately I don't have a pic18F26K80

Martin

[victorhantelmann]

First of all thank you all very much for your fast reply.
Answer 1 - for dazz:
Nothing is displaying. V0 as in datasheet at 4.5 Vcc for best contrast. If I modify contrast voltage, I can see the background rectangles so the LCD is working.
Answer 2 - for Enamul:
I have grounded R/W pin but still no change. I'm not sure if KS0066U and HD44780 are fully compatible but they are certainly close, I am still studying the datasheet.
Answer 3 - for Medelec35:
The LED is blinks about 4 times slower than 1 Hz (with the code you provided) and nothing shows on LCD.
I will verify PIC18F26K80 datasheet for OSC configuration.
It would be nice to be able to work with INTOSC and PLL to 64 MHz but since PPPv3 application has different interface names than the ones used in datasheet by Microchip it is difficult and a little confusing for me because I have to guess. I have to look into this problem much more.
Answer 4 - for all:
I rechecked the wires on my prototype board so I am posting the new schematic.

[victorhantelmann]

I checked the suggestions given by medelec35 concerning PLL, OSCTUNE and OSCON. Thank you for pointing me in that direction.
I am posting the code containing oscillator settings, this code blinks the LED at 1 Hz.
Unfortunately the LCD is still blank but at least I solved the oscillator.

[kersing]

In your (revised) schematic there is the DEM20486SYH-LY, your message subject states DEM20286SYH-LY. Which one are you using?

Anyway, when looking at the 4 bit initialization sequence for DEM20486SYH-LY (data sheet you attached, page 13) and for the LCD on the Eblock (page 46) there seems to be quite a difference. I think this display will require modifications to the LCD Start code for it to work.

[victorhantelmann]

Answer to kersing:
1. I use DEM20486SYH-LY LCD sorry for this mistake, I changed all my posts accordingly.
2. You are right, I did wrote the INIT procedure and I am attaching the code for all of you to take a look and verify it if you have time.
3. Thank you for pointing me in the right direction.
4. Unfortunately my LCD is still not displaying anything on screen, but I think that there is more to it than just the INIT procedure ... Any advice would be appreciated.
Thank you again.

[kersing]

Have you considered changing the Start code of the LCD component? Right click on the LCD component, select 'Custom code', select 'Start' in the list of component macro's and click the button 'Edit Code'. Now you are able to change the C code in the macro. By updating this macro (and using RawSend) you do not need to worry about setting/resetting the handshake signals.

Also, while working on the display code it might help to keep the clock below 30MHz. There have been reports of timing issues with high speed clocks and the LCD component. Then increase the clock speed after you get the display working.

[victorhantelmann]

Thank you all for helping, I am attaching the final test code and the INITIALISATION SUPPL for this kind of display.
It is working well and I hope that it will be useful to others since it is a cheap and rather big display.
I will follow mr. kersing advice later as soon as I will have the time, thank you sir.