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Author Topic: rgb SCREEN and vsync and hsync signals  (Read 5514 times)

pawnies20

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rgb SCREEN and vsync and hsync signals
« on: June 12, 2015, 12:01:24 AM »
Hi
After connecting a LCD RGB 24 bits screen on an  olimex A10 board, i can see with olimex debian image that signals vsync and hsync seems no work.

If i disconnect them, nothing change.

With  a scope i see nothing on the 2 pins from olimex board.

Can you help me please?

Thanx

dave-at-axon

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Re: rgb SCREEN and vsync and hsync signals
« Reply #1 on: June 12, 2015, 02:29:50 AM »
Some displays don't need the sync lines. My display is DE controlled.

You need to build your own image if you want proper control of each signal. Trying to use a prebuilt image to use a display that is not compatible with the image is a waste of time.

With your own image you have complete control over the output signals.

pawnies20

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Re: rgb SCREEN and vsync and hsync signals
« Reply #2 on: June 12, 2015, 10:34:19 AM »
Ok dave
In first, screen i must obtain:

http://www.tiikoni.com/tis/view/?id=193e911


But this is what i obtained:
http://www.tiikoni.com/tis/view/?id=32163ed

Whan i move my mouse i can see black rays
http://www.tiikoni.com/tis/view/?id=d2cb83f


My ic is a HX8238A.
Doc here:
https://www.olimex.com/Products/_resources/LCD/HX8238A.pdf

We can see if i disconnec hsync and vsync it must work in de mode (page 57)

To connect my screen , i'm using différents adaptator and total lenght to arrive in fc cable is 20cm.

i have added longest cable to see but nothing change, the screen stay the same.

I'm using same fex and same screen that lemaker's one (banana pi).

It must work but.....not

https://github.com/LeMaker/fex_configuration

I'm using these pin layer from bananapi:
http://www.tiikoni.com/tis/view/?id=c1d97b7

When connecting SEL0 SEL1 SEL2 to power with resistor it didn't work it's normal cause RGB mode is not selected;


A question, if RGB signals are inverted, colors will be changed but appearance of the screen will be ok?

I think in the kernel de mode is activated and no sync +de mode: is it possible?


Thanx
« Last Edit: June 15, 2015, 10:32:22 AM by pawnies20 »

dave-at-axon

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Re: rgb SCREEN and vsync and hsync signals
« Reply #3 on: June 16, 2015, 03:40:58 PM »
It looks like a timing issue.

Can you record a short video of the startup and put this on YouTube?

Don't use Vimeo as I can't access that website from here.

pawnies20

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Re: rgb SCREEN and vsync and hsync signals
« Reply #4 on: June 16, 2015, 04:56:56 PM »
ok but we can see nothing on the video.
Screen is white, become black and few seconds after, it shows me the  screen below:

http://www.tiikoni.com/tis/view/?id=32163ed

dave-at-axon

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Re: rgb SCREEN and vsync and hsync signals
« Reply #5 on: June 16, 2015, 06:32:52 PM »
I am sure this is a timing issue.

pawnies20

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Re: rgb SCREEN and vsync and hsync signals
« Reply #6 on: June 18, 2015, 12:48:27 AM »
You are agree it s a timing issue.
I have lcd with differents chip^: NV3035 and hx8238a

i  don't know what kind of timing put in it.

I try this under but nothing:
https://www.olimex.com/forum/index.php?topic=1549.msg7061#msg7061


[disp_init]
disp_init_enable = 1
disp_mode = 0
screen0_output_type = 1
screen0_output_mode = 4
screen1_output_type = 2
screen1_output_mode = 11
fb0_framebuffer_num = 2
fb0_format = 10
fb0_pixel_sequence = 0
fb0_scaler_mode_enable = 1
fb1_framebuffer_num = 2
fb1_format = 10
fb1_pixel_sequence = 0
fb1_scaler_mode_enable = 0
lcd0_backlight = 197
lcd1_backlight = 197
lcd0_bright = 50
lcd0_contrast = 50
lcd0_saturation = 57
lcd0_hue = 50
lcd1_bright = 50
lcd1_contrast = 50
lcd1_saturation = 57
lcd1_hue = 50

[lcd0_para]
lcd_used = 1
lcd_x = 320
lcd_y = 240
lcd_dclk_freq = 7
lcd_pwm_not_used = 0
lcd_pwm_ch = 0
lcd_pwm_freq = 22000
lcd_pwm_pol = 0
lcd_max_bright = 240
lcd_min_bright = 64
lcd_if = 0
lcd_hbp = 68
lcd_ht = 408
lcd_vbp = 18
lcd_vt = 524
lcd_vspw = 3
lcd_hspw = 30
lcd_hv_if = 0
lcd_hv_smode = 0
lcd_hv_s888_if = 0
lcd_hv_syuv_if = 0
lcd_lvds_ch = 0
lcd_lvds_mode = 0
lcd_lvds_bitwidth = 0
lcd_lvds_io_cross = 0
lcd_cpu_if = 0
lcd_frm = 0
lcd_io_cfg0 = 268435456
lcd_gamma_correction_en = 0
lcd_gamma_tbl_0 = 0x0
lcd_gamma_tbl_1 = 0x10101
lcd_gamma_tbl_255 = 0xffffff
lcd_bl_en_used = 1
lcd_bl_en = port:PH08<1><0><default><1>
lcd_power_used = 1
lcd_power = port:PH12<1><0><default><1>
lcd_pwm_used = 1
lcd_pwm = port:PB02<2><0><default><default>
lcdd0 = port:PD00<2><0><3><default>
lcdd1 = port:PD01<2><0><3><default>
lcdd2 = port:PD02<2><0><3><default>
lcdd3 = port:PD03<2><0><3><default>
lcdd4 = port:PD04<2><0><3><default>
lcdd5 = port:PD05<2><0><3><default>
lcdd6 = port:PD06<2><0><3><default>
lcdd7 = port:PD07<2><0><3><default>
lcdd8 = port:PD08<2><0><3><default>
lcdd9 = port:PD09<2><0><3><default>
lcdd10 = port:PD10<2><0><3><default>
lcdd11 = port:PD11<2><0><3><default>
lcdd12 = port:PD12<2><0><3><default>
lcdd13 = port:PD13<2><0><3><default>
lcdd14 = port:PD14<2><0><3><default>
lcdd15 = port:PD15<2><0><3><default>
lcdd16 = port:PD16<2><0><3><default>
lcdd17 = port:PD17<2><0><3><default>
lcdd18 = port:PD18<2><0><3><default>
lcdd19 = port:PD19<2><0><3><default>
lcdd20 = port:PD20<2><0><3><default>
lcdd21 = port:PD21<2><0><3><default>
lcdd22 = port:PD22<2><0><3><default>
lcdd23 = port:PD23<2><0><3><default>
lcdclk = port:PD24<2><0><3><default>
lcdde = port:PD25<1><0><3><0>
lcdhsync = port:PD26<2><0><3><default>
lcdvsync = port:PD27<2><0><3><default>

dave-at-axon

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Re: rgb SCREEN and vsync and hsync signals
« Reply #7 on: June 18, 2015, 05:06:43 AM »
You need the datasheet for the LCD to see what timing it requires. The controller datasheets don't tell you anything as they can be used to drive different size displays.

Do you have a link to the datasheet for the display you are using?

Try this and see what happens.

lcd_io_cfg0 = 0

This sets the phase adjustment on the clock. See if this has any effect. I want to see if there is any changes being detected.

pawnies20

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Re: rgb SCREEN and vsync and hsync signals
« Reply #8 on: June 18, 2015, 11:18:43 PM »
nothing change with lcd_io_cfg0 = 0

this is the datasheet

http://www.buydisplay.com/download/manual/ER-TFT035-3_Datasheet.pdf


I Think, it's connexion problem*with this parameters:
[lcd0_para]
lcd_used = 1
lcd_x = 320
lcd_y = 240
lcd_dclk_freq = 25
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 = 700
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 can see this screen:

http://www.tiikoni.com/tis/view/?id=62e1ef8

The good one is this:(the file on desktop is missing in this screenshot)

http://www.tiikoni.com/tis/view/?id=193e911

this is my installation with long cables:

http://www.tiikoni.com/tis/view/?id=c6c561c
« Last Edit: June 19, 2015, 01:03:48 AM by pawnies20 »

dave-at-axon

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Re: rgb SCREEN and vsync and hsync signals
« Reply #9 on: June 19, 2015, 05:52:58 AM »
Your datasheet link has no timing data so I found this.

http://www.displayfuture.com/Display/datasheet/TFT/ER-TFT035-3.pdf

Where did you get your timing from? The HBP of 68 seems too high. The datasheet shows 38 but does state that the data starts after clock 68. Just try first.

Try these. It's just a best case guess from looking at the timing and assuming you have RGB select via the selection pins? What state is LF0, LF1 and LF2? Are they all LOW for the RGB interface?

lcd_hbp = 38
lcd_ht = 408
lcd_vbp = 15
lcd_vt = 700

I can't see how you get 700 for the vertical timing? Looking at the datasheet I think this should be 262?

According to the datasheet, the clock is only 6.5Mhz for the RGB interface and you are using 25? Trying using 6 or 7 instead.