Take a look at our
ThinkPads.com HOME PAGE
For those who might want to contribute to the blog, start here: Editors Alley Topic
Then contact Bill with a Private Message

TP 755CX - issues with mwave, sound and modem

Older ThinkPads from the 300, 500, 600, 700 Series, iSeries, Transnote etc.
Message
Author
stamasd
Posts: 37
Joined: Sat Dec 03, 2016 5:43 am
Location: Easton, CT

TP 755CX - issues with mwave, sound and modem

#1 Post by stamasd » Mon Dec 26, 2016 10:51 pm

I recently acquired a TP 755CX. It's actually my second one, and I also have a 755CE. I've installed a new HDD (it's actually a 1GB SSD in laptop IDE form factor) and installed Win98SE on it. The install went fine, except for the following.

The mwave audio and modem functions were not detected during the install. There is no "unknown device" showing up in device manager, nor is there a modem or audio controller. I have installed the mwave features package (v2.25a), which installs fine but still does not lead to the autodetection of the mwave audio & modem. On the other 2 laptops (the previous 755CX and the 755CE) the mwave would get detected and installed at this stage.

Now, I know that some 755CX machines didn't have a mwave/DSP board. However, this one does have a DSP. If I go into setup (BIOS) I can test the DSP, and it tests fine. Also, I've installed the Thinkpad features disk, and if I go to that and select DSP it does show me the DSP as installed and with the resources it uses. However the next sections, the audio SoundBlaster compatible system and the modem system are greyed out and cannot be selected. The SoundBlaster emulation does not show any resources assigned, and the modem section although greyed does have some resources assigned, like port COM2 etc. The system has plenty of resources available, IRQ5 and 7 are free, DMA channels 1 and 2 are free etc so it's not an issue with insufficient resources.

Does anyone have any suggestions on how can I get this going? I don't really care about a functioning modem in this day and age (besides I have plenty of PCMCIA modems I could be using if I wanted one) but I want the sound to work for games.


(edit) I have used the TP755 diagnostic disk to test the DSP/audio. On the initial screen it shows as: "audio card - connected (DSP card)"; then I went on to test DSP functions, and all pass. I can actually hear the sound the DSP generates through the laptop's speakers. But Windows still can't detect it.
Current Thinkpad collection: 755CX x2 and 755CE (with a Dock II 3546); 380ED; 380XD with port replicator; 770Z with SelectaDock III; 570 with UltraBase; R52 with advanced dock.
Former members, no longer alive: 760ED.

danikayser84
Sophomore Member
Posts: 130
Joined: Thu Mar 20, 2014 8:55 pm
Location: Albany, NY

Re: TP 755CX - issues with mwave, sound and modem

#2 Post by danikayser84 » Tue Dec 27, 2016 10:34 am

I have a similar issue, I put Windows for Workgroups 3.11 on and the wave audio works and SB16 emulation works but MIDI does not? (MIDI did work under Windows 95, however) Everything else is working (did not test the modem however, I have no use for it in almost 2017, and there's not even dial up here anymore)
Current: T440p (Win10), W500 4058-CTO (Win10), T61 8892-01U (Win2000), Semi-Retired: T61 8892-01U (Win10)
Museum/Retired: T400, Z60m, T43, T42, T30, T23, A30, A31p, 600X, 600E, 380ED, 770Z, 560Z, 765D, 755CX, 755CD
Others: Dell D630, MacBook Pro Mid-2012, PowerBook G3 Pismo, AlBook 15"/1.5G

stamasd
Posts: 37
Joined: Sat Dec 03, 2016 5:43 am
Location: Easton, CT

Re: TP 755CX - issues with mwave, sound and modem

#3 Post by stamasd » Wed Dec 28, 2016 9:09 am

Still haven't solved this. I reinstalled Win98SE, still doesn't detect the DSP/SB/modem.
At some point, after docking it to the Dock II (trying to force the hardware detection routine) then undocking, I managed to have it recognize the MPU-401 port, but nothing else.

I'm stumped as to what else to do.
Current Thinkpad collection: 755CX x2 and 755CE (with a Dock II 3546); 380ED; 380XD with port replicator; 770Z with SelectaDock III; 570 with UltraBase; R52 with advanced dock.
Former members, no longer alive: 760ED.

RealBlackStuff
Admin Emeritus
Admin Emeritus
Posts: 23809
Joined: Mon Sep 18, 2006 5:17 am
Location: Loch Garman, Éire

Re: TP 755CX - issues with mwave, sound and modem

#4 Post by RealBlackStuff » Wed Dec 28, 2016 9:42 am

I'm not familiar with those machines, but could it be lack of RAM or faulty RAM, which would not show up in the (very basic) tests?
Or a low/near-dead CMOS battery?
Old BIOS/EC?
Lovely day for a Guinness! (The Real Black Stuff)
Lenovo: X240, X250, T440p, T480, M900 Tiny.

PS: the old Boardroom website is still available on the Wayback Machine
.

stamasd
Posts: 37
Joined: Sat Dec 03, 2016 5:43 am
Location: Easton, CT

Re: TP 755CX - issues with mwave, sound and modem

#5 Post by stamasd » Wed Dec 28, 2016 10:17 am

This computer has the max amount of RAM it supports, 40MB (same as the other 755CX). I replaced the CMOS battery recently. All memory tests, system board etc test fine both in BIOS and by using the diagnostic disk (which appears to use more thorough tests)

I'm not sure how to check BIOS version. In setup the following information is displayed:

BIOS part number 91G0718
date 3/27/95
model FC
submodel 01
revision 00
power management revision 1.27
setup version 1.18

Now, the latest service disk (BIOS) is 1.44, but the earliest BIOS that the 755CX shipped with is AFAIK 1.20.
All that is moot since I can't flash a new BIOS anyway. The flasher requires a fully charged battery to function, and that check cannot be disabled. I have several batteries for this model, but none of them holds a charge. Even "new" batteries that you can buy are usually no good, as they have been manufactured 20+ years ago and though stored unused, they are all dead by now.
Current Thinkpad collection: 755CX x2 and 755CE (with a Dock II 3546); 380ED; 380XD with port replicator; 770Z with SelectaDock III; 570 with UltraBase; R52 with advanced dock.
Former members, no longer alive: 760ED.

RealBlackStuff
Admin Emeritus
Admin Emeritus
Posts: 23809
Joined: Mon Sep 18, 2006 5:17 am
Location: Loch Garman, Éire

Re: TP 755CX - issues with mwave, sound and modem

#6 Post by RealBlackStuff » Wed Dec 28, 2016 11:36 am

As for mwave: see if this helps: https://groups.google.com/forum/#!topic ... hLNqnlQ2Xc

As for batteries: check the pinout and compare with a more modern battery.
If they match, or can be made to match, make an adapter cable from 755CX battery-slot to new battery-connector.
I have made such adapter-cables and can now use any shape T6x/R6x/X6x battery in any shape T6x/R6x/X6x laptop.
Great for flashing BIOS etc.

hwattys
Junior Member
Junior Member
Posts: 420
Joined: Fri Dec 10, 2004 9:14 am
Location: Central Indiana
Contact:

Re: TP 755CX - issues with mwave, sound and modem

#7 Post by hwattys » Wed Dec 28, 2016 12:00 pm

On the 755 series mWave will not install in Windows 95 or Windows 98 unless you install the "plug and play" BIOS. It will work in Windows 3.1 with the original BIOS. These models straddled the 3.1 and 95 era. There is also a Windows 95 readiness disk that it helps to run which you can find (with the BIOS package) in the legacy file mirror accessible by links posted here. The problem is that in order to do the BIOS flash you pretty much have to have a working battery, and those are hard to come by now, as noted. I have a bunch of 755 batteries and may have an extra that holds some charge but I have not tested them in years. I do have a fully working 755CX that had a working battery last time I checked.

stamasd
Posts: 37
Joined: Sat Dec 03, 2016 5:43 am
Location: Easton, CT

Re: TP 755CX - issues with mwave, sound and modem

#8 Post by stamasd » Wed Dec 28, 2016 12:12 pm

Okay, sounds like it comes down to flashing somehow the latest BIOS... Lemme see if I can find a way to force that. I have found some posts about hex-editing the flasher, and a few others about forcing a flash manually.
Current Thinkpad collection: 755CX x2 and 755CE (with a Dock II 3546); 380ED; 380XD with port replicator; 770Z with SelectaDock III; 570 with UltraBase; R52 with advanced dock.
Former members, no longer alive: 760ED.

stamasd
Posts: 37
Joined: Sat Dec 03, 2016 5:43 am
Location: Easton, CT

Re: TP 755CX - issues with mwave, sound and modem

#9 Post by stamasd » Wed Dec 28, 2016 1:54 pm

Hmm, I have 5 batteries for the 75x/76x series (they all fit in 755) but they are all dead, none will hold any charge. And it seems that unlike the later 600/770 series, you really cannot flash a 755 without a battery - at least I haven't found on this forum or elsewhere any solution for that.

Guess I'm dead in the water.

The only way out that I see is that I somehow find a working battery - but in my experience that's next to impossible.
Current Thinkpad collection: 755CX x2 and 755CE (with a Dock II 3546); 380ED; 380XD with port replicator; 770Z with SelectaDock III; 570 with UltraBase; R52 with advanced dock.
Former members, no longer alive: 760ED.

stamasd
Posts: 37
Joined: Sat Dec 03, 2016 5:43 am
Location: Easton, CT

Re: TP 755CX - issues with mwave, sound and modem

#10 Post by stamasd » Wed Dec 28, 2016 1:59 pm

RealBlackStuff wrote:As for mwave: see if this helps: https://groups.google.com/forum/#!topic ... hLNqnlQ2Xc

As for batteries: check the pinout and compare with a more modern battery.
If they match, or can be made to match, make an adapter cable from 755CX battery-slot to new battery-connector.
I have made such adapter-cables and can now use any shape T6x/R6x/X6x battery in any shape T6x/R6x/X6x laptop.
Great for flashing BIOS etc.
Tell me more please about the adapters. The 755/760 batteries are 10.8V/3AH approx. I don't have any working batteries from laptops of that era, can it be made to work with more modern batteries? I do have a few modern laptops that have working batteries. I wonder if connecting just the + and - from an appropriate voltage battery to the + and - connectors in the laptop would work, or is there more circuitry involved.
Current Thinkpad collection: 755CX x2 and 755CE (with a Dock II 3546); 380ED; 380XD with port replicator; 770Z with SelectaDock III; 570 with UltraBase; R52 with advanced dock.
Former members, no longer alive: 760ED.

RealBlackStuff
Admin Emeritus
Admin Emeritus
Posts: 23809
Joined: Mon Sep 18, 2006 5:17 am
Location: Loch Garman, Éire

Re: TP 755CX - issues with mwave, sound and modem

#11 Post by RealBlackStuff » Wed Dec 28, 2016 5:03 pm


stamasd
Posts: 37
Joined: Sat Dec 03, 2016 5:43 am
Location: Easton, CT

Re: TP 755CX - issues with mwave, sound and modem

#12 Post by stamasd » Wed Dec 28, 2016 8:11 pm

Interesting, but I don't have any working batteries from that generation of laptops. I only have modern laptop batteries in a working state, and five dead TP755/760 batteries.
Current Thinkpad collection: 755CX x2 and 755CE (with a Dock II 3546); 380ED; 380XD with port replicator; 770Z with SelectaDock III; 570 with UltraBase; R52 with advanced dock.
Former members, no longer alive: 760ED.

RealBlackStuff
Admin Emeritus
Admin Emeritus
Posts: 23809
Joined: Mon Sep 18, 2006 5:17 am
Location: Loch Garman, Éire

Re: TP 755CX - issues with mwave, sound and modem

#13 Post by RealBlackStuff » Thu Dec 29, 2016 8:53 am

Take a dead battery apart to get to the socket that fits onto the laptop's battery-plug, and remove it, but in such a way that you can still solder wires to the socket-pins.
I found the pinout of that battery on page 400(Ni-MH) or 401(Li-ion) of the HMM tpvol2.pdf.
Download here: http://ps-2.kev009.com/ohlandl/books/tpvol2.pdf

Then check what other working batteries you have and find their pinout.
Their voltage is unimportant (anywhere between 8V and 16V is good).
You'll also need a matching (dead) motherboard or interposer card (as used in 15" T4x and T6x) for that battery.
Then remove the battery-plug from either mobo or interposer in such a way that you can still solder wires to the plug-pins.
Use at least 4"/10cm of e.g. leftover flat ribbon cable (from an old PC's HDD or FDD) to solder between 755-battery-socket and mobo/interposer-plug, as per pinout on each side.
Connect your new cable between laptop and battery and start using that battery.
Enjoy!

UPDATE: Found T4x/R5x/X4x pinout: http://pinout.net/pinout-scheme/3986/LE ... y%20pinout
Lovely day for a Guinness! (The Real Black Stuff)
Lenovo: X240, X250, T440p, T480, M900 Tiny.

PS: the old Boardroom website is still available on the Wayback Machine
.

hwattys
Junior Member
Junior Member
Posts: 420
Joined: Fri Dec 10, 2004 9:14 am
Location: Central Indiana
Contact:

Re: TP 755CX - issues with mwave, sound and modem

#14 Post by hwattys » Thu Dec 29, 2016 10:33 am

Great tutorial on the battery hack. In the event that is more soldering than you want to do, this weekend I will check all the 755 batteries I have (like maybe 10-12) in my 755CX and see if I have a working one. I will post the results here. If I find one working one I would be happy to send it as a loaner for the purpose of flashing the BIOS.

stamasd
Posts: 37
Joined: Sat Dec 03, 2016 5:43 am
Location: Easton, CT

Re: TP 755CX - issues with mwave, sound and modem

#15 Post by stamasd » Thu Dec 29, 2016 12:23 pm

hwattys wrote:Great tutorial on the battery hack. In the event that is more soldering than you want to do, this weekend I will check all the 755 batteries I have (like maybe 10-12) in my 755CX and see if I have a working one. I will post the results here. If I find one working one I would be happy to send it as a loaner for the purpose of flashing the BIOS.
Thanks for the offer! If you have one, I'd be happy to pay rent+deposit on it while I'm using it for flashing.

Or else, I could probably hack something together temporarily using alligator clips and blade contacts as seen on the page: http://oldcomputer.info/hacks/tpflash/index.htm
(BTW I tried the dangerous method explained there with shorting internal wires on cells on one of my batteries, but it's so far gone that it didn't do anything; of the 3 groups of cells inside, one is completely dead with 0V, the other two have less than 2V each i.e. also dead but to a lesser degree)
Current Thinkpad collection: 755CX x2 and 755CE (with a Dock II 3546); 380ED; 380XD with port replicator; 770Z with SelectaDock III; 570 with UltraBase; R52 with advanced dock.
Former members, no longer alive: 760ED.

danikayser84
Sophomore Member
Posts: 130
Joined: Thu Mar 20, 2014 8:55 pm
Location: Albany, NY

Re: TP 755CX - issues with mwave, sound and modem

#16 Post by danikayser84 » Thu Dec 29, 2016 5:26 pm

You could try bridging a charged NiMH 9V battery over the terminals to make it think there's a charged battery inside the machine, but I don't know if it works or not (I'm lucky enough to have at least one working 755/760 battery)
Current: T440p (Win10), W500 4058-CTO (Win10), T61 8892-01U (Win2000), Semi-Retired: T61 8892-01U (Win10)
Museum/Retired: T400, Z60m, T43, T42, T30, T23, A30, A31p, 600X, 600E, 380ED, 770Z, 560Z, 765D, 755CX, 755CD
Others: Dell D630, MacBook Pro Mid-2012, PowerBook G3 Pismo, AlBook 15"/1.5G

hwattys
Junior Member
Junior Member
Posts: 420
Joined: Fri Dec 10, 2004 9:14 am
Location: Central Indiana
Contact:

Re: TP 755CX - issues with mwave, sound and modem

#17 Post by hwattys » Thu Dec 29, 2016 7:24 pm

No dice. I had 9 of them. 4 Li-ion and 5 Ni-Mh. None of them even registers in the Thinkpad "Fuel" program. All say "no battery pack present". Sorry.

stamasd
Posts: 37
Joined: Sat Dec 03, 2016 5:43 am
Location: Easton, CT

Re: TP 755CX - issues with mwave, sound and modem

#18 Post by stamasd » Thu Dec 29, 2016 7:35 pm

Well thanks for trying. BTW the Ni-MH packs should be easy enough to rebuild, much less dangerous than the Li packs.

I will try various things, and will post back if I get something working. This wold be of use to anyone who needs to flash BIOS on these old Thinkpads but has no battery.
Current Thinkpad collection: 755CX x2 and 755CE (with a Dock II 3546); 380ED; 380XD with port replicator; 770Z with SelectaDock III; 570 with UltraBase; R52 with advanced dock.
Former members, no longer alive: 760ED.

stamasd
Posts: 37
Joined: Sat Dec 03, 2016 5:43 am
Location: Easton, CT

Re: TP 755CX - issues with mwave, sound and modem

#19 Post by stamasd » Thu Dec 29, 2016 7:57 pm

RealBlackStuff wrote:Take a dead battery apart to get to the socket that fits onto the laptop's battery-plug, and remove it, but in such a way that you can still solder wires to the socket-pins.
I found the pinout of that battery on page 400(Ni-MH) or 401(Li-ion) of the HMM tpvol2.pdf.
Download here: http://ps-2.kev009.com/ohlandl/books/tpvol2.pdf
With that information I can (almost) emulate a NiMH battery pack. Any idea what the Send signal is? Fortunately these aren't SMBus batteries so it should be probably a simple signal.
Current Thinkpad collection: 755CX x2 and 755CE (with a Dock II 3546); 380ED; 380XD with port replicator; 770Z with SelectaDock III; 570 with UltraBase; R52 with advanced dock.
Former members, no longer alive: 760ED.

hwattys
Junior Member
Junior Member
Posts: 420
Joined: Fri Dec 10, 2004 9:14 am
Location: Central Indiana
Contact:

Re: TP 755CX - issues with mwave, sound and modem

#20 Post by hwattys » Fri Dec 30, 2016 8:19 am

None of the Ni-Mh I have even lights up the battery charging light on the status bar but the Li-ions do. I think it would be a relatively simple matter of cutting open the plastic case and replacing the internal cells

stamasd
Posts: 37
Joined: Sat Dec 03, 2016 5:43 am
Location: Easton, CT

Re: TP 755CX - issues with mwave, sound and modem

#21 Post by stamasd » Fri Dec 30, 2016 9:26 am

hwattys wrote:None of the Ni-Mh I have even lights up the battery charging light on the status bar but the Li-ions do. I think it would be a relatively simple matter of cutting open the plastic case and replacing the internal cells
I have opened a Li-ion pack (85G8520), it has 17500-type cells inside (12 of them, 4P+3S)welded to a custom grid made of thin nickel strips. It would be quite difficult to replace them. Removing the old cells requires cutting them from the grid, which will destroy it, and you'd need to fabricate your own method for connecting the replacement cells. There's very little extra space inside the casing, round wires of an appropriate diameter won't fir so you need to make flat connectors. And that custom harness for 4P+3S would be quite complicated especially since one of the 4P groups is split in 2+2 (the cells inside are arranged in 2 rows of 6 cells).

I tried doing something like this with a battery for a Thinkpad 770 and was ultimately unsuccessful. I just couldn't cram the new cells, strip connectors, insulation and everything back in the case in a way that would allow the case to close.

I'm thinking if I can figure what the "send" signal is on the battery pack, I could probably emulate a NiMH battery pack with an external pack of 1.2V NiMH cells (I have an enclosure that will take 8 AA NiMH cells), a resistor to provide the appropriate "therm" signal and whatever it takes to signal the laptop as "send". The problem is I can't find anywhere what the "send" is, and without a working battery chances are slim that I can reverse engineer it.

The Li-ion pack has an extra signal "select", so it'd need extra things to emulate. I like to keep things simple. therefore my idea of emulating the NiMH pack instead.

Keep in mind that my goal here is not to make a working battery pack, but only to make the laptop think that it has one for the 5-10 minutes it will take to flash the BIOS.
Current Thinkpad collection: 755CX x2 and 755CE (with a Dock II 3546); 380ED; 380XD with port replicator; 770Z with SelectaDock III; 570 with UltraBase; R52 with advanced dock.
Former members, no longer alive: 760ED.

RealBlackStuff
Admin Emeritus
Admin Emeritus
Posts: 23809
Joined: Mon Sep 18, 2006 5:17 am
Location: Loch Garman, Éire

Re: TP 755CX - issues with mwave, sound and modem

#22 Post by RealBlackStuff » Fri Dec 30, 2016 10:09 am


stamasd
Posts: 37
Joined: Sat Dec 03, 2016 5:43 am
Location: Easton, CT

Re: TP 755CX - issues with mwave, sound and modem

#23 Post by stamasd » Fri Dec 30, 2016 10:22 am

I've seen that before, but these batteries are older than that. They are not SMBus, and don't use the signals described there. The NiMH battery has only one signal to the laptop named "send"
I'm also pretty sure that the "send" isn't 1-wire protocol, as this battery predates the 1-wire standard.
Current Thinkpad collection: 755CX x2 and 755CE (with a Dock II 3546); 380ED; 380XD with port replicator; 770Z with SelectaDock III; 570 with UltraBase; R52 with advanced dock.
Former members, no longer alive: 760ED.

RealBlackStuff
Admin Emeritus
Admin Emeritus
Posts: 23809
Joined: Mon Sep 18, 2006 5:17 am
Location: Loch Garman, Éire

Re: TP 755CX - issues with mwave, sound and modem

#24 Post by RealBlackStuff » Fri Dec 30, 2016 10:57 am


Kasm279
Junior Member
Junior Member
Posts: 260
Joined: Tue Jul 19, 2011 6:07 am
Location: Ririe, Idaho

Re: TP 755CX - issues with mwave, sound and modem

#25 Post by Kasm279 » Fri Dec 30, 2016 11:37 am

Additionally, are you 100% sure your machine has Mwave? It was an option, something my 755CX did not receive.
Main: Latitude E6430
Working ThinkPads: IBM 5155, 755C, 755CX, 760ED, 380Z, 600E (x3), i1420, 570E, X20, T23, T30 x3, T43, Z61t, T60p
WIP: 701c (Broken OS), 600 (LCD), PS/2 L40SX (HDD), 570 (No lid), X31 (HDD, LCD), R51 (HDD), Z60t (HDD), X60 (HDD), T400 (LCD), T43p (?)
Dead: i1420 (Mobo, Keyboard)

stamasd
Posts: 37
Joined: Sat Dec 03, 2016 5:43 am
Location: Easton, CT

Re: TP 755CX - issues with mwave, sound and modem

#26 Post by stamasd » Fri Dec 30, 2016 12:01 pm

Kasm279 wrote:Additionally, are you 100% sure your machine has Mwave? It was an option, something my 755CX did not receive.
It's in my original post. The DSP passes all checks in BIOS and also in the diagnostic disk, and during those I can actually hear sound through the laptop speakers.
Current Thinkpad collection: 755CX x2 and 755CE (with a Dock II 3546); 380ED; 380XD with port replicator; 770Z with SelectaDock III; 570 with UltraBase; R52 with advanced dock.
Former members, no longer alive: 760ED.

olex126
Junior Member
Junior Member
Posts: 401
Joined: Tue May 29, 2007 3:46 pm
Location: London, Ontario, CANADA

Re: TP 755CX - issues with mwave, sound and modem

#27 Post by olex126 » Sat Dec 31, 2016 8:01 am

In a place long ago and far away, there was a program on the Usenet Thinkpad Users Group which modified the BIOS of the 75x series of the laptops to accept a BIOS update WITHOUT a charged battery in place. I downloaded it and used it a couple of times. The program came with a set of instructions on how to make the required 3.5" floppy disk.

I came across the disk and (printed) instructions a few months ago in a box of items that I hadn't opened since I moved here five years ago :eek: ! The disk was still readable in my desktop floppy drive.

IF I can find the box and contents again (BIG IF) I can send along the pertinent details. Failing that, a detailed search of the Usenet group's archives might produce the desired program as well.

Regards.

Dave
Previous & Collection Thinkpads: 701C A22m A30/A31p T23p x2 T30 T41 X31 various 750's 760's & 390's.

Test Benches: X41T, X60T & X61T's, various T42p-T43p's, x200 x201 x220T x230 T520 W530 T601F LED (X9000/8Gb/250SSD/W7 U)

DD: P50

"Life Is A Journey...Enjoy The Ride!"

RealBlackStuff
Admin Emeritus
Admin Emeritus
Posts: 23809
Joined: Mon Sep 18, 2006 5:17 am
Location: Loch Garman, Éire

Re: TP 755CX - issues with mwave, sound and modem

#28 Post by RealBlackStuff » Sat Dec 31, 2016 8:16 am

Lovely day for a Guinness! (The Real Black Stuff)
Lenovo: X240, X250, T440p, T480, M900 Tiny.

PS: the old Boardroom website is still available on the Wayback Machine
.

hwattys
Junior Member
Junior Member
Posts: 420
Joined: Fri Dec 10, 2004 9:14 am
Location: Central Indiana
Contact:

Re: TP 755CX - issues with mwave, sound and modem

#29 Post by hwattys » Sat Dec 31, 2016 11:28 am

I have one of those here somewhere and I can try to revive one of the Ni-Mh batteries. If I recall they do not work on Li-ion.

stamasd
Posts: 37
Joined: Sat Dec 03, 2016 5:43 am
Location: Easton, CT

Re: TP 755CX - issues with mwave, sound and modem

#30 Post by stamasd » Sat Dec 31, 2016 1:59 pm

olex126 wrote:In a place long ago and far away, there was a program on the Usenet Thinkpad Users Group which modified the BIOS of the 75x series of the laptops to accept a BIOS update WITHOUT a charged battery in place. I downloaded it and used it a couple of times. The program came with a set of instructions on how to make the required 3.5" floppy disk.

I came across the disk and (printed) instructions a few months ago in a box of items that I hadn't opened since I moved here five years ago :eek: ! The disk was still readable in my desktop floppy drive.

IF I can find the box and contents again (BIG IF) I can send along the pertinent details. Failing that, a detailed search of the Usenet group's archives might produce the desired program as well.

Regards.

Dave
You would have a big THANKS from me if you were to find that disk. :D
Current Thinkpad collection: 755CX x2 and 755CE (with a Dock II 3546); 380ED; 380XD with port replicator; 770Z with SelectaDock III; 570 with UltraBase; R52 with advanced dock.
Former members, no longer alive: 760ED.

Post Reply
  • Similar Topics
    Replies
    Views
    Last post

Return to “ThinkPad Legacy Hardware”

Who is online

Users browsing this forum: Bing [Bot] and 47 guests