Olimex Support Forum

OLinuXino Android / Linux boards and System On Modules => A13 => Topic started by: letaft on June 29, 2013, 07:52:39 AM

Title: A13 + LCD 3.5"
Post by: letaft on June 29, 2013, 07:52:39 AM
Hi,

I recently acquired an A13 Wifi and I've been trying to use it with a 3.5" TFT Display
The one I have uses a HX8238D driver http://www.newhavendisplay.com/app_notes/HX8238.pdf (http://www.newhavendisplay.com/app_notes/HX8238.pdf).

I've been modifying the .fex in the Basic 2GB image with Debian.

Based on the datasheet I have been able to get the horizontal part working, but there's something wrong the the vertical sync and only a little part of the LCD is visible with some values and in red color(see image).

(https://lh5.googleusercontent.com/-KhQgeWAXUHk/Uc5g0fHGeFI/AAAAAAAAAJ0/pdNh1GkN4FY/w784-h588-no/IMG_20130628_210639.jpg)

I'm using the 24bit interface of the LCD with the 18bit interface of the A13 the connections are like the ones in the LCD7 board.

This is the part of my .fex that I have edited from the 800x480 version:


[lcd0_para]
lcd_used = 1
lcd_x = 320
lcd_y = 240
lcd_dclk_freq = 9
lcd_pwm_not_used = 0
lcd_pwm_ch = 0
lcd_pwm_freq = 10000
lcd_pwm_pol = 0
lcd_if = 0
lcd_hbp = 68
lcd_ht = 408
lcd_vbp = 18
lcd_vt = 524
lcd_hv_if = 0
lcd_hv_smode = 0
lcd_hv_s888_if = 0
lcd_hv_syuv_if = 0
lcd_hv_vspw = 3
lcd_hv_hspw = 30
lcd_lvds_ch = 0
lcd_lvds_mode = 0
lcd_lvds_bitwidth = 0
lcd_lvds_io_cross = 0
lcd_cpu_if = 0
lcd_frm = 1
lcd_io_cfg0 = 268435456


I got the values from the page 57 in the datasheet.

When I use lcd_vt value of 524 (262*2) I got nothing on the LCD, but when I start increasing the value (700+) I got something like the previous image.

I've been playing around with the values with no luck.

Thanks for your help!
Title: Re: A13 + LCD 3.5"
Post by: Nexum1 on October 09, 2014, 04:53:01 PM
Hi Letaft,

I noticed that you were attempting to use a non-standard LCD with the A13. I was wondering if you ever got it working, and how much manual intervention it took in the end?

I want to use the arduino 2.8" LCD...
Title: Re: A13 + LCD 3.5"
Post by: alsaleem on January 17, 2015, 08:41:18 PM
I wonder if any one has resolved this problem.

Please help.

Thanks.
Ahmad
Title: Re: A13 + LCD 3.5"
Post by: pawnies20 on June 19, 2015, 01:16:46 AM
Hi, do you have a solution to this problem please.
I can see similar prolem on my screen.

Thanx