[Arm-netbook] 480 × 272 5" LCD lash up ready for testing

[luke.leighton]

On Thu, Sep 19, 2013 at 9:28 AM, joem <joem at martindale-electric.co.uk> wrote:
> On Thu, 2013-09-12 at 10:09 +0000, joem wrote:
>> Hi,
>>
>> A 480 × 272 5" LCD which costs <$15 has been lashed up for testing:
>>
>> http://www.gplsquared.com/eoma_boot/eoma_boot.html#lcd_lashup
>>
>> The LCD is a KD43G18-40NB-A1.
>> Aliexpress store sell these LCDs
>> http://www.aliexpress.com/wholesale?SearchText=KD43G18-40NB-A1
>>
>> Datasheet http://www.gplsquared.com/eoma_boot/KD43G18-40NB-A1-1.pdf
>>
>> Anyone got a time to do a time saving uSD image
>> configured for 480 x 272 operation that I can try for
>> a bit of quick verification :) ?
>
>
> The LCD was wired up with 3.3V and 18V + 100R in series
> for the back light last night.

 whoopeee!

> Notice one problem straight away.
> That particular model of LCD requires a DEN signal
> The DEN or Display ENable signal informs the LCD
> to ignore the data on the IO lines while the CPU
> is booting, or when the video bus is doing
> something unrelated to video. There is no DEN signal from
> the MEB,

 yes there is. on
http://rhombus-tech.net/community_ideas/micro_engineering_board/
 you can see it's pin 29.

 this comes from here:
http://elinux.org/Embedded_Open_Modular_Architecture/EOMA-68#Table_of_EOMA-68_pinouts
 which is pin 48.


> If the EOMA has spare pins, I recommend adding a DEN line

 already taken care of.


> At the moment the LCD is not being initialised properly.
> The boot log is here
> http://www.gplsquared.com/eoma_boot/lcd_boot_log.txt

<4>[DISP] *** Err01: Violate "lcd_hbp > lcd_hspw"
[    5.635979] [DISP] *** Err01: Violate "lcd_hbp > lcd_hspw"
<4>[DISP] *** Err02: Violate "lcd_vbp > lcd_vspw"
[    5.645902] [DISP] *** Err02: Violate "lcd_vbp > lcd_vspw"
<4>[DISP] *** Err03: Violate "lcd_ht >= (lcd_hbp+lcd_x*1+4)"
[    5.656779] [DISP] *** Err03: Violate "lcd_ht >= (lcd_hbp+lcd_x*1+4)"
<4>[DISP] *** Err04: Violate "(lcd_vt/2) >= (lcd_vbp+lcd_y+2)"
[    5.673792] [DISP] *** Err04: Violate "(lcd_vt/2) >= (lcd_vbp+lcd_y+2)"

 ok so you need to change those values so that the double-checks pass.
 just experiment until you have it ok?  although... to be honest, that
LCD's so common i'm sure you'd be able to find someone who's done this
already.

> The script.fex used is here
> http://www.gplsquared.com/eoma_boot/script.fex

 awesoome.

> Any help appreciated.
>
>
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