Hunyue Yau wrote:
I have the PSP LCD working and I am not happy with it. You can see it on my website (see .sig). The only thing good about the PSP LCD is that it is cheap in single quantities other then that, I can't think of anything good to say about it.
What about ipod/iphone displays? They look cheap too. I guess they are 320x480?
http://www.dealextreme.com/details.dx/sku.24897
http://www.dealextreme.com/details.dx/sku.24898
http://www.dealextreme.com/details.dx/sku.24896
What about ipod/iphone displays? They look cheap too. I guess they are
320x480?http://www.dealextreme.com/details.dx/sku.24897
http://www.dealextreme.com/details.dx/sku.24898
http://www.dealextreme.com/details.dx/sku.24896
Does any kind of easy accessible datasheet/information exist for these?
Søren
Frantisek Dufka wrote:
Hunyue Yau wrote:
I have the PSP LCD working and I am not happy with it. You can see it on my
website (see .sig). The only thing good about the PSP LCD is that it is cheap
in single quantities other then that, I can't think of anything good to say
about it.What about ipod/iphone displays? They look cheap too. I guess they are
320x480?
ipod video aka classic is only 320x240.
Hunyue Yau wrote:
I have the PSP LCD working and I am not happy with it. You can see it on my
website (see .sig). The only thing good about the PSP LCD is that it is cheap
in single quantities other then that, I can’t think of anything good to say
about it.
Dr. Aznar makes the compelling point.
Sure there are other interesting LCD panels out there but what are we really looking to do? A QVGA screen won’t make a good ebook reader but I bet a PSP screen will show off the OMAP3530 capabilities quite nicely.
I replaced the LCD screen on my HTC 6800 PocketPC phone (240x320) from a source on eBay. Very nice screen but goofy connector!
I have repaired SEVERAL iPods (320x240) and the first thing you find there is that there are so dang many of them. Every iPod has a different screen.
Hunyue saw some difficulty with the PSP screen but that hasn’t distracted thousands (11,807 as of this morning) from viewing the YouTube video of his Beagleboard based MID.
EarthLCD lists many interesting panels but how many of them are going to be around long term?
The PSP screen is readily available from several sources and provides a fine 16:9 format.
Hello
> I have the PSP LCD working and I am not happy with it. You can see it on
> my website (see .sig). The only thing good about the PSP LCD is that it
> is cheap in single quantities other then that, I can't think of anything
> good to say about it.That's the best point, along with its wide availability : COTS
replacement parts are both cheap and easily available, and should
always be preferred.
I wouldn't count on long term availability of this particular LCD given that
this is largely sold as a replacement part for a product that is getting old.
One factor that you might not be considering is a system as a whole. I built
the interface for my Beagle MID handheld. For some applications, this LCD may
be just fine. I am not saying it is a bad LCD, my point is that it I am
unhappy with it given my goals. Keep in mind that LCDs run a range of
electrical requirements. One LCD I used before had requirements for things
like a -17V contrast/bias voltage so compared to that, the all positive
voltage requirement is better. This is all relative.
However, given the response, I might reconsider things.
Which do you tihnk will sell better - $100 kit, LCD included, that
can be plugged to the bb directly, or a $200 kit which requires
specific LCDs that may or may not be available in the future?
I'd provide a third choice, a LCD kit that includes the LCD and behaves
better.
So I'd be interested in a board
Will respond off list to keep things O(n)T(opic)for the list.
BTW will displaying on the LCD port disable DVI output, or can both be
achieved (with different res and possibly different framebuffers)
The signals feeding the LCD connector and the DVI are the exact same signals.
So different res simultaneously is not possible as wired. The TRM alludes to
alternative wiring where the signals can be muxed between multiple LCDs but
things are not wired in a way that the muxing would work.
So, I have made it either LCD or DVI. This is enforced by using the disable
signal for the DVI as the LCD enable signal. Saves a pin and prevents some
confusion in figuring out why a DVI monitor won't work at 480x272. The FB
driver (at least the new one, DSS2) can be setup to let you select which
output in software pretty easily.
> What about ipod/iphone displays? They look cheap too. I guess they are
> 320x480?
>
> http://www.dealextreme.com/details.dx/sku.24897
> http://www.dealextreme.com/details.dx/sku.24898
> http://www.dealextreme.com/details.dx/sku.24896Does any kind of easy accessible datasheet/information exist for these?
Søren
The lack of data is a big killer for a lot of LCDs. If it wasn't for the
datasheet for the Sharp LCD, I would not been able to verify the source of
the problem was the LCD and not an issue elsewhere. LCDs can do weird things
when the specs are exceeded. Like the LCD on the SDP (big OMAP eval board)
appearing washed out but otherwise functional when I gave it a bad refresh
rate due to a silly bug where I used a clock should be a freq instead of a
period or vice versa. Other that it appears to works.
> > http://www.dealextreme.com/details.dx/sku.24897
> > http://www.dealextreme.com/details.dx/sku.24898
> > http://www.dealextreme.com/details.dx/sku.24896
>
> Does any kind of easy accessible datasheet/information exist for
> these?
> SørenThe lack of data is a big killer for a lot of LCDs. If it wasn't for
the datasheet for the Sharp LCD, I would not been able to verify the
source of the problem was the LCD and not an issue elsewhere. LCDs
can do weird things when the specs are exceeded.
I totally agree, which is why I asked if any public datasheet/specification
for these modules exist. In case not it's really a no go using them
(although they are cheap I admit), unless you want to spend a huge amount of
time reverse engineering the signaling from an original IPod/IPhone, which
though might be possible in case you really want... 
/ Søren
Hello
I wouldn't count on long term availability of this particular LCD given that
this is largely sold as a replacement part for a product that is getting old.
That's the point! The PSP was such a big hit you'll certainly find
spare parts on line for a long long time, at very decent prices. Look
at the gameboy advance.
And unlike brand new LCDs , the specs will match, because they are
sold for replacement!
However, given the response, I might reconsider things.
It seems to me I am not alone looking for a simple extension board,
with additional UARTs, MMC, LCD, I2C. Ideally it would support a
simple COTS remplacement LCD, but would also feature a LVDS port for
advanced uses.
Maybe you should just ask people what they need, and what would their
pricerange be?
Which do you tihnk will sell better - $100 kit, LCD included, that
can be plugged to the bb directly, or a $200 kit which requires
specific LCDs that may or may not be available in the future?I'd provide a third choice, a LCD kit that includes the LCD and behaves
better.
Sure that's better, but the only important things are 1) price 2) availability.
And then again, unless you intend on building thousands per month,
your limit will be LCD. COTS replacement parts are usually a good idea
for any research project.
Søren made a good point with iphone replacement screens. Unfortunately
there are too many different models. That's why I had suggested the
PSP screen. You could also consider the PDAs LCDs (dell, ipaq...) or
the netbooks LCDs - say eeePC 700 replacement screens. You'll
certainly find them for some time too.
A good test is ebay and google: the more sellers, the most available
is the screen. And you can simply indicate to the people purchasing
your board to get them online
The signals feeding the LCD connector and the DVI are the exact same signals.
So different res simultaneously is not possible as wired. The TRM alludes to
alternative wiring where the signals can be muxed between multiple LCDs but
things are not wired in a way that the muxing would work.
Thanks for your clarification. I hadn't fully understood that.
So its not possble to use two different DVI monitors with different
resolutions. So to have two displays there is the hdmi port and the
s-video port?!
Robert
Søren Steen Christensen wrote:
I totally agree, which is why I asked if any public datasheet/specification
for these modules exist. In case not it's really a no go using them
Yeah, sorry, for a moment I completely forgot about this bit. I did a quick google search and the only hint I found was here
"Sorry - we don't have any information on the connectors or pinout. You may want to refer to Apple iPhone hacking website."
So indeed this is a problem. There are some iphone linux websites and booting video on youtube but I couldn't find any LCD driver source (or even linux kernel source). And they may just draw into alrady initialized framebuffer anyway.
So its not possble to use two different DVI monitors with different
resolutions. So to have two displays there is the hdmi port and the
s-video port?!
Right - One third option is to find a SPI connected display in case only a
low resolution (i.e. 320x240@30fps) 2nd or 3rd display is needed...
/ Søren
Hello,
I'm trying to put this LCD screen with touchscreen on the
BeagleBoard :
http://radiospares-fr.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=0476533
I saw in your discussion about how connecting your LCD Screen.
I don't know if connect the LCD Signals (available on the BeagleBoard)
to my LCD Screen will work ( I noticed you are speaking with the
others guys about buffer, level translators...)
I would be happy if you can help me to resolve my issue.
Thanks,
Bastien
You must design an adapter board to convert from the 1.8V levels to the 3.3V levels required by this display. As it is CCFL and not LED, you will also need to find a high voltage CCFL lamp driver power supply as well to run the backlight and add the control circuitry to turn it on and off. The touchscreen interface device is also required. You can use the I2C port on the LCD expansion connectors for that, or if you connect to the expansion connecotor as well, you can use SPI. The board will also provide the connectors required to connect to the cables on the LCD panel.
Gerald