1 (edited by neutron spin 2010-09-01 13:42:01)

Topic: LCD display support

Hello new soon to be hackerboard user. Would it be possible to use an LCD as in the original board?  Most likely the code has to be changed.  What LCD display would be best to use? I suppose using an LCD composite monitor would work. I really would like just the display......Thanks.

Re: LCD display support

OK....just thought of a way to get an economical way to look at some output from the device....a 7" cheapy car LCD monitor...has composite video input and saw some for around $60 shipped on E-bay....not great resolution but a good bench setup for testing...OK now I am off to the hackerthon..!!... smile

Re: LCD display support

It would be possible, yes.  The 44-pin header on the back breaks out all of the LCD pins.  It'll require some driver hacking, though, as the kernel checks at boot to see if it's running on a hacker board, and switches the display to composite video.

Re: LCD display support


The PROpendous board is using the same cpu and has a cheapo 240 x 320 resistive touch screen attached to it. http://code.google.com/p/propendous/sou … PROpendous

I just happen to have a few similar screens lying around here, ordered on a blue Monday from Formike, Shenzen for less then 20$ a pop. http://www.wandisplay.com/doce/product-detail-87.html

They both use the ILI9325 chip.

I would love to connect the screen to something and the Chumby hackerboard looks like a good target. However I've just stumbled upon it and haven't taken a good look at the schematics yet.

Would you reckon it's possible to just use a few GPIOs to connect it to the LCD on a breakout board?


Re: LCD display support

Looking at a datasheet I found, it looks like that should support DOTCLK mode.  Because it's based off the chumby One, it already has the drivers for a 320x240 LCD with resistive touchscreen.  You'd just need to fab a board that goes from the 44-pin header on the back to a ribbon connector for the LCD module, then switch the screen to 320x240 (E.g. using switch_output), then modify the LCDIF registers using e.g. regutil.  Either that, or modify the kernel to natively use the LCD rather than switching to composite video.

6 (edited by ekrem 2011-01-14 06:53:07)

Re: LCD display support

This is my lcd project  480 * 272 pixel 18 bit

project in progress  no ended  I  have some pixclock timing problems

some photo link is  http://imxcommunity.org/photo

a lot  of thanks to  Tz and Chumbylurker for kindly helps of this project

Re: LCD display support

Ekrem , can you post a howto for this. Getting an LCD out from the chb would quadruple its appeal. An lcd easily available on adafruit or sparkfun would add to the glory since most of the others are selling in a language few understand.

8 (edited by ekrem 2011-03-14 22:29:55)

Re: LCD display support


My lcd Project details are below  thanks again Tz and chumbylurker


innolux  AT043TN24  480 * 272 + touch from ebay

2mm 44 pin male 2mm connector from ebay   or 2mm  2x 40 pin header

2mm to 2.54 converter  from  http://www.proto- advantage.com/store/product_info.php?products_id=3800084 

But this for 40 pins we need  44 pin so  add  4 pin  with  dremel

40 pin fpc to dip adapter whit  connector for lcd

from http://www.proto-advantage.com/store/pr … id=3400013
and main board from http://www.proto-advantage.com

very importand script thanks for chumbylurker adapted for my lcd by me

we must firstly run this script for correctly work new lcd

/mnt/storage/switch_output -l

regutil -w HW_LCDIF_CTRL=0x000b0820
regutil -w HW_LCDIF_VDCTRL4=0x1e0
usleep 50000
regutil -w HW_CLKCTRL_PIX=0x60
regutil -w HW_LCDIF_CTRL1=0x010f2101
regutil -w HW_LCDIF_TRANSFER_COUNT=0x011001e0
regutil -w HW_LCDIF_VDCTRL0=0x1130000a
regutil -w HW_LCDIF_VDCTRL1=286
regutil -w HW_LCDIF_VDCTRL2=0x2c000233
regutil -w HW_LCDIF_VDCTRL3=0x002b000c
regutil -w HW_LCDIF_VDCTRL4=0x000401e0
regutil -w HW_LCDIF_NEXT_BUF=$(regutil -r HW_PXP_S0BUF | cut -d' ' -f4)
regutil -w HW_LCDIF_CTRL_SET=1

we need root file set correctly re building kernel for whitout any kernel panic
link is: wget http://files.chumby.com/source/falconwi … .mx233.tgz

and we are editing lcd_lms430.c  for correctly settting lcd size pixlock and pixl porch size

#define DOTCLK_H_ACTIVE  480
#define DOTCLK_HF_PORCH  2
#define DOTCLK_HB_PORCH  2

#define DOTCLK_V_ACTIVE  272
#define DOTCLK_VF_PORCH  2
#define DOTCLK_VB_PORCH  2

and remove these lines
// don't check power limits for now -- bunnie revisit
    //    if (reg_set_current(data->regulator, bl_to_power(intensity))) {
    //      printk( "power limit exceeded.\n" );
    //        return -EBUSY;
    //    }   thanks to Tz

path is linux-2.6.28.mx233\linux-2.6.28\linux-2.6.28.mx233\arch\arm\mach-stmp3xxx

and re editing chumbyfbfw.c file  path is linux-2.6.28.mx233\linux-2.6.28\linux-2.6.28.mx233\drivers\video

in this file change porch pixel like below and esspecialy change to this file  pixclock lines
.pixclock  = 60000, 

after then these steps

Firstly we must change lcd type to lms430 before rebuilding kernel  make ARCH=arm menuconfig command and save

And writing zImage to sdcard via config_util --cmd=putblock --dev=/dev/mmcblk0p1 --block=krnX < /mnt/storage/zImage command

and reboot ,you see some changes on lcd screen then running imgtool or chumbyflashplayer.x

sorry for my english

Re: LCD display support

Thanks for the detailed info. Your english is just fine.