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Raspberry Pi2 320x240p via translating modeline to <hdmi_timings>

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WalkToFreedom:
I posted this in the Pi forums but didn't get a response so thought I would try here

https://www.raspberrypi.org/forums/viewtopic.php?f=38&t=124456&p=835368#p835368

I am trying to get the Pi to output 320x240p. I have had some success, via these settings:


--- Code: ---hdmi_group=1
hdmi_mode=8

--- End code ---

But hdmi_mode=8 is actually 720x240p.

I know this modeline works fine for the CRT (TV conversion RGB via SCART) as I have had it running via an ArcadeVGA (it's actually an ArcadeVGA modeline):


--- Code: ---Modeline "321x240@59,4Hz 15,7KHz (60Hz)" 6.460 321 336 368 412 240 242 245 264  -hsync -vsync

Modeline syntax: pclk hdisp hsyncstart hsyncend htotal vdisp vsyncstart vsyncend vtotal [flags] Flags (optional): +HSync, -HSync, +VSync, -VSync, Interlace, DoubleScan, CSync, +CSync, -CSync

eg: Modeline "1600x1200" 155   1600 1656 1776 2048   1200 1202 1205 1263
 #           (Label) (clk)     (x-resolution)        (y-resolution)
 #                     |
 #              (pixel clock in MHz)
--- End code ---

Is it possible to translate the modeline to an <hdmi_timings>? This is what I came up with, but screen just stays blank? Am I missing some other setting?


--- Code: ---hdmi_timings=<h_active_pixels> <h_sync_polarity <h_front_porch> <h_sync_pulse> <h_back_porch> <v_active_lines> <v_sync_polarity> <v_front_porch> <v_sync_pulse> <v_back_porch> <v_sync_offset_a> <v_sync_offset_b> <pixel_rep> <frame_rate> <interlaced> <pixel_freq> <aspect_ratio>

hdmi_group=2
hdmi_mode=87
hdmi_timings=321 0 15 32 76 240 0 2 3 19 0 0 0 60 0 6460819 1
--- End code ---

Thanks!

obcd:
Are you sure your hdmi 2 vga adapter is capable of handling such resolutions?
If I remember well, some are limited in what they can convert.

WalkToFreedom:

--- Quote from: obcd on November 05, 2015, 06:03:34 pm ---Are you sure your hdmi 2 vga adapter is capable of handling such resolutions?
If I remember well, some are limited in what they can convert.

--- End quote ---

Yeah, I wondered about that too but my guess is it just converts whatever the HDMI res is, it does work on:


--- Code: ---hdmi_group=1
hdmi_mode=8 # 720x240p
--- End code ---


So it can output as 240p:

bleck:
These links may be useful. The first is a listing of modelines for different broadcast standards and game consoles, while the second is a timing calculator

http://www.geocities.ws/podernixie/htpc/modes-en.html
http://www.epanorama.net/faq/vga2rgb/calc.html

One bug in it is that the name of the Modeline you enter has to be of the form "HRESxVRES". Any other characters will screw up the the calculation. For example, for NTSC SNES, I use Modeline "256x224" 5.370 256 274 299 341 224 236 239 262 as input and get

[*User-Defined_mode,(256X224)]
PIXEL_CLK   =   5370
H_DISP   =   256
H_FPORCH   =   18
H_SYNC   =   25
H_BPORCH   =   42
H_SYNC_POL   =   0
V_DISP   =   224
V_FPORCH   =   12
V_SYNC   =   3
V_BPORCH   =   23
V_SYNC_POL   =   0
INTERLACE_ENABLE  =  0

WalkToFreedom:
Hi. Many thanks for your reply. I had actually come across both of those pages. Taking a second look though and punching the numbers has revealed that mine are up the wacky do. Weird, nothing tricky there just plain wrong. Hmmmm. Will try the new ones and see how they work out. Thanks!

Oh, I'm assuming you're not using a Pi??? If so, where do you configure the modelines???

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