Hi,
I have to buy an raw LCD display (2''- 5''). Can you give me some
advice about the right model to buy?
Alex.
Sure. The one that you have the adapter card for. These displays do not plug directly into the board. You must have level shifters, power circuitry and back light supplies for them. So, if you are in a position to build such a board, the options open up. If not then currently options are limited. The only two I know of that are readily available are:
http://www.beagleboardtoys.com/ which is a 4.3" panel, not 3.5 as the website says and the same display can also be purchased from https://specialcomp.com/beagleboard/index.htm
Other people have talked about doing displays, but they have not really become visible or readily available as far as I know.
Now, if you do indeed want to buy a raw display and have the ability to design your own card, there are 100s of options. But, you need to be careful. If this is to be used in a product, some of those displays may not be available next year for purchase. The basic requirement is that the display interface be a RGB interface, with VS, HS, and clock, up to 24 bits. A 16 bit display (565) will also work.
I hope this help!
Gerald
Hi,
I am investigating using a PSP 3000 display with a beagle board. they are high res, relatively bright and best of all, inexpensive and widely available. they will also be around for awhile. If you search ebay you can find them for around $25 and you can still get the old ones made years and year ago.
They have a single standard .5 mm connector and use a LVDS interface.
I have the ability to dothe circuit design, pcb design and checkout. I plan to use the sparkfun pcb service so the circuit would be available to anyone who wants it for about the cost of the parts.
My problem? I have been unable to find the interface specification for the display. So my plan B is to reverse engineer it.
I do not have access to a psp3000. I have a breakout board that is intended to be installed between the psp3000 motherboard and the display. The idea is to put this inline and then use a scope and logic state to look at the signals to understand the pinout.
1.) does anyone have access to the psp3000 LCD specification. or
2.) Does anyone have a psp3000 and the ability to reverse engineer the pinout. I could send you the breakout board to make it easy to have access to the signals.
take care ted
This is the LCD used on the products that are located at the two links I sent out earlier.
Gerald
Thanks for your answer.
I can build PCB with level adapter and power supply. I'll be ride this
road.
i'm going to do some question about the information that you have
send to me
http://www.beagleboardtoys.com/ which is a 4.3" panel, not 3.5
as the
website says and the same display can also be purchased from
https://specialcomp.com/beagleboard/index.htm
did you mean this display: https://specialcomp.com/beagleboard/order.htm
LG LB043WQ1-TD01 LCD panel 4.3" 480x272 LCD touchscreen
can i connect this direct to beagleboard xM or I need RevC?
Now, if you do indeed want to buy a raw display and have the
ability to
design your own card, there are 100s of options. But, you need
to be
careful. If this is to be used in a product, some of those
displays may not
be available next year for purchase.
so have I to contact the manufacturer and ask to him?
I would like to use this one:
http://search.digikey.com/scripts/DkSearch/dksus.dll?lang=en&site=US&WT.z_homepage_link=hp_go_button&KeyWords=T-55226
do you think this display will be avaible the next years?
The basic requirement is that the
display interface be a RGB interface, with VS, HS, and clock,
up to 24
bits.
did you mean 24bit per color? or 8bit per color? My display have 8 bit
per color, did it work on BeagleBoard xM?
A 16 bit display (565) will also work.
What does it mean 565, is it dispaly name o standard?
thank you a lot...
Alex
so the
LG LB043WQ1-TD01 LCD panel
4.3" 480x272 LCD touchscreen
available at:
https://specialcomp.com/beagleboard/order.htm
is the same display of
PSP 3000
available on eBAy?
is PSP 3000 a touch screen?
thanks,
Alex
See below.
Gerald
Thanks for your answer.
I can build PCB with level adapter and power supply. I’ll be ride this
road.
i’m going to do some question about the information that you have
send to mehttp://www.beagleboardtoys.com/ which is a 4.3" panel, not 3.5
as the
website says and the same display can also be purchased from
https://specialcomp.com/beagleboard/index.htmdid you mean this display: https://specialcomp.com/beagleboard/order.htm
LG LB043WQ1-TD01 LCD panel 4.3" 480x272 LCD touchscreen
can i connect this direct to beagleboard xM or I need RevC?
It works and Rev C and should work on the -xM, but I have not seen anyone get it working on the -xM as the SW is requires changes to work on the -xM.
Now, if you do indeed want to buy a raw display and have the
ability to
design your own card, there are 100s of options. But, you need
to be
careful. If this is to be used in a product, some of those
displays may not
be available next year for purchase.so have I to contact the manufacturer and ask to him?
I would like to use this one:
http://search.digikey.com/scripts/DkSearch/dksus.dll?lang=en&site=US&WT.z_homepage_link=hp_go_button&KeyWords=T-55226
do you think this display will be avaible the next years?
I have not used Optreex, so you eed to ask them. Most liley it would be.
The basic requirement is that the
display interface be a RGB interface, with VS, HS, and clock,
up to 24
bits.did you mean 24bit per color? or 8bit per color? My display have 8 bit
per color, did it work on BeagleBoard xM?
I mean 24 bit color, 8 bit per color (Red, Green, Blue) on each pixel, hence 24 bit color per pixel.
A 16 bit display (565) will also work.
What does it mean 565, is it dispaly name o standard?
It is a standard 5 bits of red 6 nits of green and 5 bits of blue. 16 bits per pixel.
Hi.
thanks for very helpful answer!
another question about the display.
The raw LCD interfaces are the same on both XM Rev. C4, isn't true?
if the interfaces are the same, Why should I change the software to
use the LCD on xM?
Alex
The pins and signals on the connectors are the same. But the pins on the processors are different. That is why you have to change the SW. Take a look at the schematics for each board and you will see what I am referring to.
Gerald
The pins and signals on the connectors are the same. But the pins on the processors are different
That might explain the washed out colors in the beagleboard toys vga module
After a brief review of the schemantics (both c4 and xM), the DM3730 TRM and the xM SRM, its not very obvious why the pin mux needs to be changed (Im sure there is a reason, but at least by now its now immediately obivous after going thru the docs)
Here are the main questions:
If the signals in the LCD expansion headers are connected to the DVI_DATAn lines, then why it makes a difference the processor pin muxing? I mean, lets use P11 header pin 4 for a moment, it is connected to DVI_DATA0 signal, and this signal is connected to either DSS_DX0 (AG22) or DSS_D0 (H26) that correpsond to LCD Pixel Data bit 0 in either pin muxing mode (Legacy or 720p, according to Table 14 from xM SRM), that pin the the LCD header will get the blue0 signal in either mode
or is the header pin is connected directly to AG22?
And, according the file board/ti/beagle/beagle.h from UBoot (beagleboard-Validation), it is already booting in legacy mode (standard configuration)
MUX_VAL(CP(DSS_DATA0), (IDIS | PTD | DIS | M0))
AG22 is already in DSS_D0 mode
Am I missing something? (of course Im, but what it is? 
)
Lioric
The Toys’ VGA module should work fine if the SW is set up correctly for that monitor. Also, the Toys VGA board is not designed for real long cable, so make sure you don’t have a cable over 3 feet or so.
The pins mux needs to be changed because on the -xM different pins drive the signals off the processor as we had to move them in order to obtain 720 HD on some of the signals… If you don’t change it, it won’t work. Look at the schematic more closely and read the System Reference Manual for more information on the pins that move. If you use existing -xM SW that works on the -xM then nothing needs to change in the mux other than the resolutio and timing that is needed by the display. Default settings will not dirve the LCD correctly as the resolution and timing won’t be correct. If you try using SW configured for a rev C4, then the signals won’t be connected, requiring the pin mux change.
Gerald
Toys VGA board is not designed for real long cable, so make sure you don’t have a cable over 3 feet or so
Yep, using a ~20cm custom cable
If you use existing -xM SW that works on the -xM then nothing needs to change in the mux other than the resolutio and timing that is needed by the display
Timings and resolution are stable and correct, the timings for the resolutions that needed have been defined and are working as intended (displayed image is correct, but not their colors)
According to your input, we can safely say that if we are using the default xM uBoot and the HDMI display gets the correct color bits, then the LCD expansion header should be using the same correct signals, then there is no need to change pin mux, right? (the same display connected to the HDMI port has correct colors, but connected to the vga port is washed out)
In that case then there is something more that needs to be configured, as we have tested a couple of Toy’s VGA boards, and both produce the same washed out colors
I suppose that I will test by changing the mux to:
H26 dss_data0
H25 dss_data1
E28 dss_data3
J26 dss_data3
AC27 dss_data4
AC28 dss_data5
AH26 (sys_boot0) dss_data18
AG26 (sys_boot1) dss_data19
AF18 (sys_boot3) dss_data20
AF19 (sys_boot4) dss_data21
AE21 (sys_boot5) dss_data22
AF21 (sys_boot6) dss_data23
Should the following pins set to SAFE MODE then?
AG22
AH22
AG23
AH23
AG24
AH24
Lioric
After another review of the SRM and the schemantics, is seems that changing the mux of the pins is of no help without actually a hardware modification (resitor pack RP7 and RP2 change to RP1 and RP5)
I will continue to figure it out what you mean with “The pins and signals on the connectors are the same. But the pins on the processors are different. That is why you have to change the SW.” (on -xM), as I was in the process of creating a board with a SN75LVDS83A to dirve the LCD directly, but after your comment then I suppose it wont produce the correct colors either
Im wondering if my BeagleBoard has an issue in the LCD header, after all, Circuitco told me that Toy’s VGA board should work without modification (and Gerald latests comment seem to agree with this), but I dont have an ociloscope to verify this
Is there any person that has succesfully connected a LCD via the LCD header on -xM?
Lioric
Pin muxing does not need to be changed if you are using the base -xM kernel. Pin muxing is fine. It does not need to be changed. I am working from memory here as I don’t have access to schematics, but pin 1 of P13 on the LCD header voltage of the -xM was changed and may have to be set via SW. I do not recall if the VGA board uses that voltage or not. It was 3.3V on the Rev C4 version.
Have you tried running a color bar display over the VGA to see what you get?
Gerald