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sona1111
April 10th, 2010, 06:55 AM
hello community. I did my best to try to find that this was the correct forum to post this in before i posted it. And im pretty sure, i am very sorry if its not, though, and i will delete it and put it somewhere else in that case. anyway:

A long time ago when visiting my grandad (i was younger at the time, about 5-6 years ago.), i somehow came across the fact that he had an old laptop somewhere. And he gave it to me, but requested i delete the files on the hard drive (some may have been personal) I remember it did boot even though it had been sitting for awhile, and their was some kind of GUI interface, but i also remember i deleted too many files and ended up making it so that it could not boot from the hdd. Eventually i god mad at it and put it away.

5 or so years later, i have decided to try to learn assembly language, and the book i have checked out is old and has most of its examples run in dos. I noticed that old computer again, and thought i would give it a shot. Well, eventually i got obsessed with trying to completely fix it to a workable state again, and maybe even better. Thats the end of the story, heres whats up with the thing:

It you didnt notice the title it is a laptop style computer called "IBM PS/2 L40 SX" At first the best i could do was to get it to boot from a floppy, the hard drive was never detected. Whenever i tried to use fdisk it beeped and said none were detected. Eventually i found what the problem was here, the backup battery was dead. I successfully replaced this. I also found out, though, that something was wrong with the standard hard drive in there. I keeps spinning up and staying for about 5 seconds, then shuts off, spins up again shuts off again, it does this about 20 times, then shuts off for good. I believe it is broken somehow, but i still have it if any of you know how to fix this. Instead, i have decided to use a bigger hard disk (a little under 7 GB) from an ibm thinkpad. At first i had bucketloads of problems with this because it keeps recognizing it as only 7 MB, but then i found this sweet program, ezdrive, that actually rewrites your bios or something and allowed me to use the HDD correctly. I followed its install procedure and then installed Dos 7.1 with the windows 3.1 Add on. (http://ms-dos7.hit.bg/) (I figured this old computer might not be able to handle the win98 add on) Anyway it finally boots from the HDD, but here is the first problem i have to ask about that is not solved. Using dos normally from the HDD constantly freezes at random points. If i use the simple "dir /p" command in the c: directory, it freezes after displaying the files, it also freezes when trying to run many programs. What might be causing this?

I have a few other random questions about this PC too:

The main battery is completely dead, and i am going to try this tutorial to fix it: http://hpholm.dk/L40SX_battery-pack.html
has anyone else had success with this?

I noticed another small battery inside the computer in a yellow casing that looks like 3 small barrels, mounted above the main battery holder. It is most likely long dead too, what is it used for and how do i replace it?

I know memory upgrades are still available for this system, but what about this "math co processor" i have heard of, any change of getting one?

I saw on the motherboard their are a few places with two pins free, is it possible to install a standard DC fan on any of these? I know it would fit but i dont want to try anything without knowing the electronics of it.

Is it possible to get a replacement keyboard for this thing? the Down-Arrow key seems only semi functional.

Finally, i noticed some other threads in this forum about getting a LAN card into these old Pcs. I have to say it would be extremely awesome. It that in the least bit possible for this laotop? i Know its possible to install a modem in the side, but what about a LAN card?



thanks for reading...

BuggZ
April 10th, 2010, 12:26 PM
According to the L40SX Quick Reference manual you can install a math coprocessor and the memory can be increased to 18MB. You will need a reference disk for the L40SX if you need to make any changes or if your backup battery is dead. The Reference Disk also includes a hardware test program. I may have an original Reference Disk I can copy if you need it.

sona1111
April 10th, 2010, 02:18 PM
Hello. I do know its possible to install them, but with the system this old, is it possible to obtain a math coprocessor? I got a refdisk, and replaced the battery so thats ok. I think i may have found the problem with the freezing. When i chose FAT16 instead of FAT32 in EZdrive, it seems theirs still a few moments of freeze in the same places, but it does go away. I also drastically lowered the size of the partition that the OS is installed in. It could be either of these things but that problem seems to be fixed.

Can anyone answer the other questions, if they get a second? Again the network card would be awesome but that is currently something that is completely out of my zone.

I Also have one more question to add to the list:

I saw on the motherboard their are a few places with two pins free, is it possible to install a standard DC fan on any of these? I know it would fit but i dont want to try anything without knowing the electronics of it.

modem7
April 10th, 2010, 03:46 PM
Hello. I do know its possible to install them, but with the system this old, is it possible to obtain a math coprocessor?
Note that a math co-processor is not going to make the computer run faster, per se. What it will do, is for programs that are math co-processor aware (e.g. certain spreadsheet programs, certain CAD programs), it will allow those programs to execute faster.

Math co-processors for old computers can be purchased from places like eBay. You need to ensure that you get the correct one for the L40 SX.


I saw on the motherboard their are a few places with two pins free, is it possible to install a standard DC fan on any of these? I know it would fit but i dont want to try anything without knowing the electronics of it.
Does your motherboard match the one shown at http://www.walshcomptech.com/ohlandl/8543/8543.html ?

sona1111
April 11th, 2010, 04:20 PM
yes, thats the one.

modem7
April 11th, 2010, 11:28 PM
yes, thats the one.
As you may have seen, directly under the diagram is listed certain items on the motherboard, including jumpers and links. There's nothing there about a fan, and so I think I can write with some confidence that there's nothing on the motherboard designed to connect a fan to.

sona1111
April 12th, 2010, 10:39 AM
I know your not supposed to use them for a fan, but this computer can get hot so i thought it could use a fan, is it possible to tap power from the battery input? (J26A and J26C + and -) Its possible that voltages from the battery are already converted to DC so i might be able to run some wires.

Also, is it possible to get a replacement keyboard for this thing? the Down-Arrow key seems only semi functional.

lutiana
April 12th, 2010, 03:14 PM
I know your not supposed to use them for a fan, but this computer can get hot so i thought it could use a fan, is it possible to tap power from the battery input? (J26A and J26C + and -) Its possible that voltages from the battery are already converted to DC so i might be able to run some wires.

Also, is it possible to get a replacement keyboard for this thing? the Down-Arrow key seems only semi functional.

Throw a volt meter on the pins and see what voltage you get. 5v or 12v would mean you might get away with it. But first I would get it running 100% before making such mods, otherwise you are introducing another possible fail point that would be hard to isolate.

As for the keyboard, see if there is a part number on it, and just google it. It is very possible that some one out there has one for sale.



Finally, i noticed some other threads in this forum about getting a LAN card into these old Pcs. I have to say it would be extremely awesome. It that in the least bit possible for this laotop? i Know its possible to install a modem in the side, but what about a LAN card? Chances are yes. I have not read the specs for the thing, but I am guessing is you can add a modem you can probably find a LAN card for it, I am assuming you have a PCMCIA slot on the thing. Make sure if you get one, that it has DOS/Win drivers.



I noticed another small battery inside the computer in a yellow casing that looks like 3 small barrels, mounted above the main battery holder. It is most likely long dead too, what is it used for and how do i replace it?I would have thought that was the BIOS battery, but you said you allready replaced the "the backup battery". Does the laptop maintain the proper date and time? Hold the various BIOS settings? If so, then that yellow thing may not be a battery, or if it is then it is used for something else. Can you post a picture?

As for the freezing issue you are having what size partitions are you running (FAT16 or FAT32?)? What version of EZ-Bios is it? Have you tried using an off the shelf version of DOS like MS-DOS 6.22?

EDIT: The keyboard part number is PT-IBM-1396181 - Google is your friend when it comes to restoring and finding parts.

lutiana
April 12th, 2010, 03:20 PM
The main battery is completely dead, and i am going to try this tutorial to fix it: http://hpholm.dk/L40SX_battery-pack.html
has anyone else had success with this?


Not a very good guide. But if I am understanding it right you can crack the battery open and replace the cells inside with standard AA rechargeables. I don't know how effective this may or may not be, but since the thing is not working it is worth a try. You may also be able to buy a new batter here (http://www.ebatts.com), they seem to have a very large selection of batteries available.

Edit: Ebatts did not have one, but a quick google search and I found a battery here (http://www.directron.com/ibml40sxb1.html?gsear=1) for $70

sona1111
April 13th, 2010, 06:01 PM
Sorry for the long reply. No, i have not given up. :)

I got the pictures you crave.

First off, the keyboard:

before i spend money on a new one, i was wondering if anyone else was dumb enough to mess up their keyboard before like this and fix it:
http://i174.photobucket.com/albums/w98/sona1111/IMG_3420.jpg
http://i174.photobucket.com/albums/w98/sona1111/IMG_3421.jpg
the story: Their actually was something to provoke this. One of the 3 plastic coverings around the brass screw holder thingies that keeps the keyboard secure broke off. (i have managed to save the brass thingy) This made one side of the keyboard pop up which was annoying and might end up breaking the other holders too. Anyway, i was stupid and i guess i thought that the keyboard was sealed up. I put some super glue in the plastic hole to secure the brass thingy again. Not only did it not work, but a small amount of the glue got into the keyboard. this made both the "right arrow" and "down arrow" keys non functional. I have kind of solved this by waving a small screwdriver through the electronic sheets (which the glue used to be sticking together). Now the right arrow works again but the down arrow is only half functional, sometimes its really annoying to press it. So, is their any safe way to get this keyboard apart to check for remaining glue? In the meantime i have drilled a hole through where the plastic holder used to be and put a screw through it to hold down the keyboard.

-----------

Next, the battery:
http://i174.photobucket.com/albums/w98/sona1111/IMG_3423.jpg
http://i174.photobucket.com/albums/w98/sona1111/IMG_3424.jpg
It is a battery, and it is rechargeable. (or it was lol.) It has been out of the computer a while and has not seemed to cause any change. O_o
Anyway this is where it was originally:
http://i174.photobucket.com/albums/w98/sona1111/2-1.jpg
And this is where it plugs in:
http://i174.photobucket.com/albums/w98/sona1111/1-2.jpg
(note these light green bands are just circles i drew in mspaint)
------------
This is the hard disk i put in there. unfortunately even though it works correctly it does not secure to the cage normally, i have to use just one rather badly positioned screw:
http://i174.photobucket.com/albums/w98/sona1111/3-1.jpg
Maybe i will drill holes in there in the future
Also #2 is the recently replaced backup battery (NOT the other battery), and #3 is where i believe the modem (hopefully network card) would plug in. No idea what that port is.

And another note on that subject, i have seen two other solutions besides a network card (even though i would prefer that more) a "IBM PS/2 COMMUNICATIONS CARTRIDGE I" which looks promising but i cannot find for sale ANYWHERE, and a "parallel port network adapter. Which could also work but i do not know if it would work in dos. Their are no PCIMA slots, by the way. (but im guessing #3 is a type of earlier version of the PCIMA thing)

------------

Finally, here are those two jumpers i saw, the first one is prolly a no-no because their is already a jumper attached to 2 of its 3 pins:
http://i174.photobucket.com/albums/w98/sona1111/4-1.jpg
But the second one (located between the memory upgrade slots):
http://i174.photobucket.com/albums/w98/sona1111/5-1.jpg
Looks promising, at least to me, because it looks like where you can plug a fan in on desktop computers (but that might not apply here at all, no idea) Their are plenty of ventilation slots around the laptops case for air to escape.

sona1111
April 15th, 2010, 10:18 AM
bump?

lutiana
April 15th, 2010, 10:50 AM
I'd say just buy another keyboard.

According to the Mobo layout that yellow 3.6v battery is a "J32 Standby battery". Not sure what that is to be honest, but my guess is if you did not replace it you would probably be fine, though a 3.6v 45mAh Ni-Cd battery should not be too difficult to locate, you may need to steal the connector from the old one.

Also, that expansion slot looks like it is only for a fax modem, but I can't tell from the doc linked in a previous post (here (http://www.walshcomptech.com/ohlandl/8543/8543.html)). So you may be stuck with a parallel port nic or something like it.

Lastly, those jumpers you are thinking about using as fan headers don't look like they are designed for that. My guess is that they have something to do with the memory or possibly the keyboard (based in their location). If you want to put a fan in there you may need to tap power from somewhere else, and that could be quite a project.

sona1111
April 15th, 2010, 11:12 AM
thanks for the reply. Is it possible to have more specific information about the parallel port network adapter? Have you ever set one up yourself? will it work in DOS?

thanks.

lutiana
April 15th, 2010, 12:19 PM
thanks for the reply. Is it possible to have more specific information about the parallel port network adapter? Have you ever set one up yourself? will it work in DOS?

thanks.

Search the forums, other people have done it. I have not.

IBMMuseum
April 15th, 2010, 12:25 PM
Here (http://www.ibmmuseum.com/ohlandl/8543/8543.html) is some information too. There is a 16Mb EOS SIMM that was originally for the IBM Server 320/520 that can modified to work as an 8Mb module, allowing two converted modules to be used to obtain the full 18Mb. I've done the conversion, and have a math coprocessor on one of my units (I'll find the pictures in a moment).

The planar expansion is just for a proprietary FAX/modem. If you are lucky enough to find the "Communications Cartridge", an external housing and cable for a half-length ISA card, you can put an 8-bit Ethernet or Token Ring NIC in there. It was designed for that purpose.

EDIT: Here (http://www.IBMMuseum.com/L40SX16M.jpg) is a picture of the modified SIMMs in place (with a math co-processor in the socket)...

I thought the link provided by someone else for William Walsh's L40SX page was http://walshcomptech.com/ps2/L40SX.htm, so I posted a duplicate...

sona1111
April 15th, 2010, 07:06 PM
thanks, are you saying that the co processor actually Does do something? =P

if so, ill look into finding one.

I do not have any use for a modem, my house uses Ethernet. Also i have no idea what a "token ring" is (though i have seen it numerous times while searching for this) and i do not know if modern Ethernet connections are "8 bit" -_-

Ill take a look at that memory thing, though.

IBMMuseum
April 16th, 2010, 08:24 AM
thanks, are you saying that the co processor actually Does do something? =P

if so, ill look into finding one.

I do not have any use for a modem, my house uses Ethernet. Also i have no idea what a "token ring" is (though i have seen it numerous times while searching for this) and i do not know if modern Ethernet connections are "8 bit" -_-

Ill take a look at that memory thing, though.

In the picture it shows that I am using the 387SL low-power version. Unless you have a program that uses the math co-processor it will just idle and drain battery power. Any PLCC version of a 387SX/387SL should work for you.

Looks like I also have the FAX/modem on that unit. Probably the most maxed-out unit I have of several L40SX's. I do need to drop in a bigger hard drive like you have done though.

Since I have a Communications Cartridge I can take some pictures of it. Despite the L40SX being a 16-bit system, the single slot of the Communications Cartridge is 8-bit. Maybe I'll put a 3Com Ethernet adapter in there just to get it on the network.

sona1111
April 16th, 2010, 08:30 AM
If you get pictures/have any luck connecting with that cartridge, please do tell. =D

also, how many l40 sx's do you have laying around? any spare keyboards for sale?

IBMMuseum
April 16th, 2010, 08:35 PM
...how many l40 sx's do you have laying around? any spare keyboards for sale?

Ive got four complete L40SX units, and some accessories (no spare keyboards)...

sona1111
April 22nd, 2010, 11:25 AM
Sorry but i need to bump this up once again to ask for help. =S

My order of AA rechargeables came in today so i could complete this: http://hpholm.dk/L40SX_battery-pack.html

Well, i have done it just the way i was instructed and i am having a problem . Apperantly they ARE connected correctly becaus the computer does dectect the battery. However what exactly happens is: I put in the battery and over the period of one second it:
1) displays the charging arrow
2) fully charges (all of the bars fill up)
3) goes back to acting like their is no battery.
All of this happens very fast, but i can tell it actually did charge because If i turn on the computer with just the battery the screen flickers on for a split second.
Is their any way i can get it to charge correctly? Could this have something to do with the dead "Standby battery"?

thanks.

mikey99
April 22nd, 2010, 12:06 PM
Did you replace the old cells with NiCad or NiMh batteries ? The pictures in that link
show NiMh batteries, but I think they may have different charging characteristics than
the original NiCad cells.

Also, are the new batteries fully charged when you put them in the pack ?

sona1111
April 22nd, 2010, 12:49 PM
i believe they are NiMH, but the tutorial said that was OK.

They were not fully charged...should they be?

mikey99
April 22nd, 2010, 01:18 PM
i believe they are NiMH, but the tutorial said that was OK.

They were not fully charged...should they be?

In most cases the NiCad charger should work okay with NiMh batteries. If it
works for the person that created the tutorial it should be okay. It shouldnt
really matter if the batteries are fully charged, I was just wondering if somehow
the charger was detecting they were already fully charged.

If you have a voltmeter it would be a good idea to measure the total voltage
just to make sure they are connected correctly and no cells are bad. Looking
at the pictures the batteries are all attached in SERIES which should yield
9 X 1.2v = about 10.8 VDC

sona1111
April 22nd, 2010, 03:44 PM
thanks for your reply..again.

I am kind of mad at it right now. I actually charged the batteries on a standard charger, and lined them all up end to end and took a wire from each and to the + and - and it still will not run!

I actually figured out annoyingly that the little "chargeup and back to normal" that appeared just happens when you put the battery in, even if their are no cells attached!

So..i have no idea what is wrong...unless its just something with the main board.

mikey99
April 22nd, 2010, 06:13 PM
Were you able to measure the total voltage and verify its about 10.8 ? I guess its possible
that soldering the wires to the battery could damage the battery although i have soldered
many like this and never had a problem.

Will the computer run when attached to AC power even though the battery was dead ?

sona1111
April 22nd, 2010, 07:52 PM
yeah, the computer runs fine on wall power. (did you read the rest of the thread? no offense)

and i do not have a voltmeter currently. :(

i tested a few of the batteries in other devices and they seemed to work fine, but i guess i can test all of them.

lutiana
April 22nd, 2010, 10:32 PM
Are you lining the batteries up in series or in parallel?

I highly recommend that you get yourself a voltmeter. They have some really cheep ones at radio shack (under $20) that work well as basic units.

sona1111
April 23rd, 2010, 05:33 AM
they are in series.

that is what it appears to be in the tutorial.

mikey99
April 23rd, 2010, 10:51 AM
I found this spec on the L40 battery, so the cells in series is correct :

Replacement Battery Pack for IBM PS/2 Model L40SX (Beige)
Features: NiCad Main Battery Pack. Voltage: 10.8 Volt. Capacity: 2400mAH. Brand: ENERGY+

I have never seen any 2400mah NiCad cells so I wonder how they can make that claim.
If they're actually using NiMh batteries that 2400mah sounds reasonable.

sona1111
April 23rd, 2010, 07:40 PM
well i found the problem... Getting the voltmeter was a very good idea.

anyway something was wrong with the wire i was using...copper and normal metal do not mix.. i guess..

anyway with 9 batteries in series i am actually reading about 12.4 volts on the meter. FYI
I can now get the computer to start on batteries but the alarm goes off right away and it goes into standby before i can do anything. Charging it after this results in a short amount of charge time.

Is their any way to stop the computer from automatically entering standby when it detects "low battery"? I do not think the battery, 9 new AA cells, would really drain completely in 10 seconds.

thanks.

sona1111
April 24th, 2010, 08:47 AM
Also, i just got that pocket Ethernet adapter. (xircom)

I put put it in the parallel port and plugged it in and it lights up, however the self test on the floppy says it is not detected.

not sure what this is about.

Maverick1978
July 22nd, 2010, 12:53 PM
Did you ever get the problem with your battery pack solved?

I also have an L40sx I'm planning to restore. I've been toying with the idea of wiring up the battery pack as you've done.

Right now, I've got to replace the hard drive and replace both internal batteries (IIRC the smaller one in your pictures allows the computer to stay alive while one swaps the internal battery packs, while the larger lithium cell near the a/c adapter is for the CMOS). I also need the flip-down cover for the parallel port and a/c adapter on the back side, but I doubt I'll be able to find one without purchasing a parts unit. I was lucky with my purchase - it came with 12mb RAM, the internal dialup modem, a NIB trackpoint mouse, the the reference diskette, the demo diskette, 3qty keyboard overlays, and all documentation. I'm also toying with the idea of modifying a 16mb SIMM to max out the RAM in this system. We'll see.

ch_123
July 25th, 2010, 04:29 PM
I saw your thread when I was looking for information on the L40 keyboard, I might be able to help you replace or fix it -

IBM produced an external version of the L40 keyboard, called the Model M4. Here's a picture of one -

http://geekhack.org/picture.php?albumid=11&pictureid=129

I have a similar version of this keyboard (M4-1, which has a Trackpoint), and from dismantling it, it looks like IBM took the keyboard unit from the L40 laptop, and just designed a housing for it. The M4's keypad connects to a controller board inside the housing using the same sort of ribbon cables in your picture.

There's a company called Unicomp that ended up owning IBM's keyboard division that still sells these M4 keyboards. Their site claims that they are out of stock, but they do a repair service, and the people who run the company are really helpful, if you asked for a replacement keypad for an IBM M4, they might be able to help you.

That failing, you can try opening the keyboard assembly itself. On the underside, there's a little plastic wedge in the center, if you push it down you can slide the thing apart. I'd say that where the dead keys are, you will see a tear or erosion of the membrane traces. This can be repaired using conductive glue to patch up the failure in the traces.

There used to be a guy on eBay who sold the special "Trackpoint" (a rather nifty mouse that could be converted into a trackball) brand new in box for $5, unfortunately I can't find any...

http://www.usimperio.com/recycled/product_images/ibm/ibm_trackpoint.jpg