Succeed to install a 12.1" SXGA+ LCD for thinkpad x40 / x41

[force]

These are pins 17-20 for the two panels:

Code: Select all

Pin     Stock   BOEHydis
17      (NC)    EDID 3.3V
18      (NC)    GND
19      GND     EDID CLK
20      GND     EDID DATA

I feel more comfortable with grounding all four pins instead of leaving the EDID power rails floating. I haven't traced the actual board yet, so I don't know what it's connected to on the other side.

I figured the (stock) X31/32 bios wasn't using EDID information since it's locked at XGA regardless of the installed panel. I'm guessing that the modified one just has SXGA+ hardcoded in place of XGA, however that's done.

[mojo-chan]

It should be fine to just connect them all without any modification.

It looks like it's just a simple serial ROM. Having the supply lines floating won't hurt it.

[plympton]

Hmm.. got my X41 tablet LCD in today - looks like a bust.

Connected it to my X32, and the backlight comes on, but the LCD shows nothing - not even garbage. I put the old panel back on, and it's fine.

The X31 LCD is an 1axg01m / 07k9760 / 11p8225
and the X41T LCD is an HD12x21-351 FRU 93p5599

They SHOULD be plug compatible from what I read in the datasheets, but I can't tell - the cables appear to be different in what they connect.

Here's a like with some pictures:
http://www.theimagedepot.com/p665750142 ... #h1bf83399

It was worth the risk for the experiment, but I'm not sure I'm up for soldering a new cable at this point. I'll try and take a photo to show the difference.

Any tips on troubleshooting this?

-Dan

[fasterbybike]

I've bought a very rough X31 with an intermittent mobo fault, my HV121P01-100 SXGA+ panel has arrived and I'm ready to start with this project. If I can get it to work on the X31, I will port the changes over to my X32 (which is too precious to use as a test bed).

BUT, I've run into trouble at the first hurdle: The X31is fitted with a IAXG01M XGA LCD. Comparing the datasheets for the two LCDs shows the following pin connections :

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Pin  XGA       SXGA+
1     GND      VDD
2     GND      VDD
3     RES       GND
4     RES       GND
5     GND      RIN0-
6     CLK+     RIN0+
7     CLK-      GND
8     GND      RIN1-
9     RIN2+   RIN1+
10   RIN-      GND
11   GND      RIN2-
12   RIN1+   RIN2+
13   RIn1-    GND
14   GND      CLK-
15   RIN0+   CLK+ 
16   RIN0-    GND
17   GND      EDID3.3v
18   GND      VSS
19   VDD      EDID CLK
20   VDD      EDID Data 

Spot the difference ?
Ignoring the EDID lines on the HV121P01, the lines appear to be connected in a mirror image on the LCDs. Is this for real, or am I misreading the data sheets ? Is one sheet giving the layout of the LCD and the other giving the layout of the cable ? Or was a different LCD and cable used on some X31s ?

Has anybody else got this far yet and have a definitive answer ?

[fasterbybike]

The X31 LCD is an 1axg01m / 07k9760 / 11p8225
and the X41T LCD is an HD12x21-351 FRU 93p5599

They SHOULD be plug compatible from what I read in the datasheets, but I can't tell - the cables appear to be different in what they connect.

Dan, see my post above. I reckon the X31/2 LCD is not compatible with either the X41 Tablet or the the X60 Tablet LCD. Here's why ...

The X31 uses an IAXG01M LCD which has a DF19KR-20P-1H connector
The X41T uses a HT12X21 LCD which has a DF19L-20P-1H connector
The X60T uses a HV121P01 LCD which has a DF19L-20P-1H connector

The Hirose datasheet shows the **KR** connector is designed to be mounted to the circuit board in reverse to the **L** connector. The datasheet shows pin 1 (marked by a small triangle) at a different end of the KR connector (cf the L connector) but the way the connectors are mounted to the LCD means that pin 1 is at the left of both LCDs when viewed from the back. The pinout on the X31 is a mirror image of the pinout on the X41T/X60T LCD.

It's time to look into mounting the LCD cable reversed . If this works then it's time to make a short adapter cable. I'm not sure how the guy in the original post (the linked site is now gone) managed to make it work.

HTH

David

[fasterbybike]

OK, reversing the cable at the LCD certainly brings results. The resolution is still XGA and tiled on the the larger SXGA+ LCD.

See attached pictures. Now time to order some connectors - but getting late here (NZ) so a job for the weekend

[force]

haha, yeah, I was going to suggest just flip the cable around.

It's good that you were able to get this far; this basically validates the hardware steps. Upon further reading, it seems like the tiling behavior is _exactly_ what is seen on the X60/X61 with only the panel replaced (and pins rerouted accordingly on the X6*). A BIOS modification is required now, since both the X3 and X6 are locked at XGA and don't use EDID or anything else to poll the display resolution.

[fasterbybike]

Interesting that the part LP121X04 (LG LCD FRU 11P8224 ?) has its pins arranged in reverse to the IAXG01M (IDTech LCD FRU 11P8225) yet there is only one LCD cable in the HMM. Time to open the X32 and check exactly what is inside that machine.

[plympton]

OK, reversing the cable at the LCD certainly brings results. The resolution is still XGA and tiled on the the larger SXGA+ LCD.

See attached pictures. Now time to order some connectors - but getting late here (NZ) so a job for the weekend

Thanks for guinea pigging on this one! Now I'm going to trim my cable and see if it works. I already connected it the "wrong" way, so I'm worried that something could be fried. Looking at my cable pictures, it DID look like they were reversed. I didn't (don't) have the spec sheets, so I wasn't sure - it was just by visuals for me.

Dang.. I need to get some work done today, too.

Quick tested it - looks BEAUTIFUL! Now the rest of the mods.. anyone know where to get the connectors? I *MIGHT* be able to just flip the connector with the existing cable, but I'm afraid I'll pinch the cable over time. What I might do is cut and strip the wires on my X41 cable, since it's not a ribbon, and stuff them inside the X31's cable connector... hack city, but it could work.

http://www.theimagedepot.com/p665750142 ... #h11d427e9

-Dan

[force]

Are you talking about the 20-pin connectors for the LVDS cable? If so, the part numbers are on the LCD datasheet (both the BOEHydis and the stock LG Philips). I believe erik on these forums bought some from Digikey, and you may have similar success from similar electronics suppliers (jameco, mouser, etc.).

[mojo-chan]

If you have a spare cable, it is possible to mod it.

[plympton]

I just twisted mine. Worked great (for now - will see long term, but I'm hopeful)

So, cramming an X41 XGA screen into an X32 actually works surprisingly well. It feels a little more "Brown" than the old screen, which was also a BOE-Hydis (and pretty decent as well). I chose not to move the frames around, and rely on the black sticky foam to hold the LCD in place while I got the frame back on.

It's pretty tight, and I'll probably go in an do a better job in the future, but for temporary, it works pretty nicely. I might try and re-center it again, too, as it's about .5mm - 1mm too far to the left, but no missing pixels. I just like my displays centered.

-Dan

[mojo-chan]

Yeah, sorry, that's what I meant by "mod", I was a bit distracted when writing that

I repair PCs for a living, and have had to twist the cable a couple of times for clients who desperately wanted a particular laptop up and running (often due to legacy ports, it's hard to get a laptop with a real parallel port these days) and where replacement screens were not available. I was worried about long term reliability, but they seem to have been fine.

[fasterbybike]

Good work guys / gals. I'm going to have to wait until the weekend till I get time to look at the BIOS. Till then

[plympton]

What's the going rate on an SXGA+ display these days - is the best place still eBay? (US purchase)

-Dan

[force]

I opened up my X32 and the panel that's installed is a BOEHydis HT121X01-100. I can take some pictures if anyone is interested. I'm not having much luck finding the datasheet for it, though.

Dan: I purchased one off of eBay for ~$250, but it was one with AFFS which should have better viewing angles and all. I thought I had been pretty careful in selecting the panel, but it came with the Wacom digitizer. For now, I'm leaving it intact and just testing the screen without assembling it into the lid, which I know will require mechanical modification.

[force]

Just out of curiosity, what was the behavior of the reversed cable? I'm seeing the screen displaying nothing (not even the IBM logo on startup) with the backlight turning on.

[plympton]

Just out of curiosity, what was the behavior of the reversed cable? I'm seeing the screen displaying nothing (not even the IBM logo on startup) with the backlight turning on.

Yep, that's it. Just nothing - makes you think you have a dead screen. Flip the cable around, and bingo, it works great. The easiest way is to just trim the cable's side lockouts (the "wings), so you can put the cable in backwards.

Why they did it that way is beyond me. Anyway, I'm typing from that machine now, so I can confirm it works.

-Dan

[plympton]

I opened up my X32 and the panel that's installed is a BOEHydis HT121X01-100. I can take some pictures if anyone is interested. I'm not having much luck finding the datasheet for it, though.

Dan: I purchased one off of eBay for ~$250, but it was one with AFFS which should have better viewing angles and all. I thought I had been pretty careful in selecting the panel, but it came with the Wacom digitizer. For now, I'm leaving it intact and just testing the screen without assembling it into the lid, which I know will require mechanical modification.

That's is the same as the one from my X32 - it's actually a pretty decent screen compared to the LG-Philips from my X31.

http://www.theimagedepot.com/p665750142 ... c#h987525c

Did you think you bought just the LCD, or did you know you were getting the digitizer? The X41 Tablet digitizer was really easy to remove - just 2 or 3 screws and a positional "nub". The plastic protection screen had sticky tape, which I used an X-acto to cut free.

Just be gentle and take your time, and all should go well.

-Dan

[force]

Word of caution to anyone thinking about trying this mod- make sure you get the right parts!

Different variants of the same LCD panel have different pinouts. For example, the BOEHydis HT121X01-100 has a pinout compatible with the X3*, and the HT121X01-101 pinout is (I think) compatible with the X6*.

I wrongly assumed that the variants retained the same pinout. Of course, datasheets for certain LCD panels are nigh impossible to find, so one has to be resourceful in figuring out which model has what pinout.

Update: I took a photo of the panel that I have (HV121P01-101) and traced the connections. The pins match up to the X3* panel pinout. Of course I find this out after I sew my X32 back up. I think at this point I'm just going to keep the X32 fully assembled and try the mod on the X60s. I should really figure out if the panel will even fit first.

Update 2: I looked at [url=http://www.theimagedepot.com/p665750142 ... #h14e6f290]the panel connector image[url] that Dan took and traced the lines. The image I took of the -101 panel shows the correct order, yet I wasn't able to get even the tiled display when I tried. Strange. It's getting late here so I'll take another wag at it tomorrow.

[fasterbybike]

I've now got a copy of a modified X31/32 BIOS, which is said to work with the SXGA+ LCD. I'll disassemble it tomorrow to see which modules have been changed - I'm cautious about bricking the mobo so will check it thoroughly first before I flash the changes required.

[fasterbybike]

Tonight's job is to install the modified BIOS onto the test machine and see how it works.
I think I'll need to make a short extension cable to reach from the folded X31 LCD cable to the HV121P01-100 LCD.

For those who find it easier to buy from Farnell, the part numbers for the extension cable are:
1719152 DF19G-20S-1C(05) HOUSING, 1MM, 20WAY
1719151 DF19G-20P-1H(56) RECEPTACLE, 1MM, R/A, 20WAY
1719158 DF19A-2830SCFA CONTACT, DF19, AWG28-30
plus you'll need cable and shielding tape (which I already have from another project).

More later ...

[fasterbybike]

Here's the results of the mod so far ...

A bit hard to see but the resolution is 1400x1050 !!!


To install the BIOS, I followed this sequence. I downgraded the existing BIOS in the X31 to version 3.1 so the attempt to reapply the 3.2 mod'd BIOS would work. I then got a copy of the latest diskette BIOS (3.2) from the lenovo website, and extracted it to a diskette. I compressed the BIOS (*.WPH) file I had been given, renamed it to the same as the extracted BIOS data file, set the Date / Time / Readonly attributes on this compressed BIOS data file and copied it to the diskette overwriting the existing one. Then run the BIOS update ... and it worked.

My next steps. Open the lid of the X32, swap over the cables and mod the new panel attachments to fit into the shell. If the LCD cable will not fit, then wait until the parts are available at Farnell (website said to phone, I did and was told to wait until mid September !).



HTH

David

[force]

Congratulations on getting things to work out!

As I'm trying this on an X60s (fallback is the X32), the LCD pinout is different than the cable so an adapter is necessary. I priced out the connector parts on digikey (I'm in the US, and they happened to be closer than Mouser (I'm impatient, I know =P)) and the receptacle is ~US$5.77 alone.

Since I don't have the crimper tool (I'm somewhat confident that one can get by without it), I opted instead to just buy a X60t cable which uses discrete wire for about the same cost. I might still have to pick up the connector to make things clean on the other end, but it's a start.

[mojo-chan]

A bit hard to see but the resolution is 1400x1050 !!!

EPIC WIN!

I really wish I had a screen now. Can't wait to see how you get on with the X32.

[Teflon77]

Congrats !!

But we need more pics !

[fasterbybike]

No time to continue with the lid assembly this weekend - but the following wkd should be OK. Patience is a virtue ?

And I may have found another source of LCDs - more later.

Cheers

D

[fasterbybike]

More progress. I've got a photo of my X32 all put back together with the SXGA+ screen. I decided in the end that I would not need to make a cable extension.

The LCD cable needed to be gently folded, the tabs on the LCD connector shaved off so it would fit into the LCD back-to-front. I've also fastened it to the back of the LCD panel with a wide piece of adhesive tape to ensure correct alignment and prevent strain on the flexible part where it exits the lid.

The LCD need all the metal and plastic tabs removing - a belt sander in a fixed jig made quick work (but take care to cover the screen surface).

The metal rails from the XGA screen were unscrewed from that screen and refastened to the SXGA+ screen with double sided tape. The two wifi aerials were then fastened with double side tape to the metal rails and the whole assembly was screwed back into the X32 lid. The Bezel fitted with no problems.

Here's the preview


A picture of the finished product can be viewed at
http://img220.yfrog.com/img220/784/picture042ogd.jpg (Warning large image and an annoying popup comes with the free hosting).

Any more questions - please ask.

[mojo-chan]

Wow, that is truly impressive!

I am surprised at the amount of modification you had to do to make the LCD fit. Maybe a different model would be easier. Still, it looks factory fitted, a really nice job.

[Terrahawk]

I *so* need to do this to my X31! I've really been enjoying the SXGA+ display on my T42p and it's disappointing when I have to use the X31 (it is smaller and more mobile, and better suits my line of work).

So, I need (in summary):
1 x HV121P01-100 SXGA+ display panel
1 x modified X31 BIOS
1 x Plenty Of Time To Do This

I'm looking forward to repeating this procedure