Crystalfonts 4 x 16 help

TC · 2007-08-07 22:01

Hello all,
I just bought a display from Crystalfonts. But I am having trouble gitting it to work. I am using "Improve LCD Demo" from Steve Almond. I changed LINELENGHT from 20 to 16. when the demo runs I get jerbish on the display, also only lines 1 & 3 are lit. as the demo starts up you can see all 4 lines activate, but then 1 & 3 are on. I am still learning to program in SPIN so please be easy on me. I have included the datasheat for my display.

thanks
TC

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deSilva · 2007-08-08 04:22

The display offsets for line 3 and 4 are $10 and $50 respectively - this is typical for 4x16 displays; it is different from 4x20 displays, where theses offsets are $14 and $54.

Change that in your driver...

TC · 2007-08-08 04:53

That did not do anything. I dont think the driver is Initializing my display right. I am going to try to make my own driver and see what happen.

TC

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We all make mistakes when we are young………That’s why paste is edible!

deSilva · 2007-08-08 15:07

TC said...
I am going to try to make my own driver

This is an excellent idea!

But I also post a driver by Marcel Majoor, which I configured for a four line display in nibble mode. Works fine!

Edit:
I think I also changed the control pins

  CRs        = 13                                           ' Connected I/O for RS signal
  CRw        = 14                                           ' Connected I/O for RW signal
  CE         = 15                                          ' Connected I/O for E  signal

The original driver had 8,9, and 10, which is more logical... but you can of course use whatever pins you like

Post Edited (deSilva) : 8/8/2007 3:30:19 PM GMT

TC · 2007-08-08 23:54

deSilva, Thank you for the driver. It is very easy to understand for a beginer, but It did not work. I do not think it could be the display or my wiring. because I hooked it up to my computer and using CFAH_Wintest from crystalfontz, and it worked like it should. so now I am thinking it is the Initializition, but I don't know yet. I have included pics to show what I am gitting. also on LCD-101, only "hello world" was to be on the display.

Thanks

TC

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We all make mistakes when we are young………That’s why paste is edible!

Post Edited (TC) : 8/8/2007 11:59:25 PM GMT

TC · 2007-08-09 00:25

Just to see if crystalfontz has there own way of controling the display. I installed LCD Smartie, set it up for a basic 4 x 16 HD44780 controled display. and it is having no problem displaying all 4 lines.

thanks

TC

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We all make mistakes when we are young………That’s why paste is edible!

deSilva · 2007-08-09 18:40

This IS strange.... You use it in 4-bt mode don't you?
Try doubling the "Delay" in line 270.
This driver - and most others -do not check the "busy" condition, to avoid reading from the display

TC · 2007-08-10 01:21

I would first like to thank you deSilva for all you time and help. 2nd It still is not working right. at this point Delay is set to 20000. I have it hooked up using the pinout that you provied. It has to be somthing simple that we are just not seeing. I have attached my test program so you could take a look. please be gentle, I am still learning.

TC

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We all make mistakes when we are young………That’s why paste is edible!

TC · 2007-08-10 02:23

something has to be wrong. using a BS2 and parallax's basic program (·Parallel_LCD_2X16.bs2 ) made for a 2 x 16 display I have line 1 and line 2. when befor I only have 1 & 3. there has to be somthing I am missing

TC

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We all make mistakes when we are young………That’s why paste is edible!

deSilva · 2007-08-10 03:47

One very easy thing: You have to end ALL YOUR STRINGS with a ZERO-delimiiter. This convention is taken from the C-language; it is quite elegant on one hand, but has severe drawbacks on the other.......
Whatever, add ",0" after your string. This is what the string(.....) constructions does automatically.

This is a very good explanation for the look of the screen shot you provided: The driver tried to copy A LOT of memory to the display

I also add the test program from Marcel for safety.

Post Edited (deSilva) : 8/10/2007 3:56:46 AM GMT

TC · 2007-08-10 23:39

WOOOOOOOHOOOOOO!!!!!!......

It is working. Thank you deSilva for all your help. now I have a reason to learn spin

TC

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We all make mistakes when we are young………That’s why paste is edible!

Crystalfonts 4 x 16 help

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