IBM trackpoint question for modding

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Input Nirvana

13 Oct 2012, 04:28

The separate full size keyboard track point with it's own little pcb has been available to mod via the IBM KPD8923 for quite a while. I heard a rumor that the IBM RT3200 V:5NTW may be constructed like the IBM KPD8923. If this is true, it would be another source of the coveted trackpoints for mods we've used. Is there anyone who has one or can find a pic of the interior of one of these? I've taken a look and have come up dry.

The only other option is to finally take the more readily accessible laptop track points and Gorilla Glue an extension. Which I will do soon if this rumor proves to be false.

The second question is has anyone determined an easily accessible, inexpensive, laptop track point to use?

I posted this on GH as well.

forcefollow

13 Oct 2012, 05:40

Hi IN..

I believe aries' would have detailed insightin salvaging trackpoint for the mod you described.
I thought I saw him post here (or was it GH) last year.

I gave up working on this mod when I saw ergodox :p actually I'm too lazy to learn electronics from scratch

Are you going to implant one of those in your kinesis?

User avatar
Input Nirvana

13 Oct 2012, 06:11

I've already installed a trackpoint from a KPD8923 in my split Kinesis. It's flawless. I had purchased several of them, but I've been a bit too generous over the last 2 years and gave a couple away, now I'm short :)

But I wanted to find another option anyhow, for versatility and maybe there's something better, driver-wise. So rather than buy another KPD8923, the benefit is the long pointing stick. But I thought I'd see what else can be used, and if nothing else, possibly extend the short laptop pointing stick, some glues are definitely strong enough.

Thank you for the link...going for a visit right now....

forcefollow

13 Oct 2012, 06:54

well, if it's about the height and drivers, I only found one from neko's keyboard room
look the same as my M13's trackpoint (if not bit shorter) though.

um, how do you come into conclusion that it will me more cost-effective harvesting trackpoints from these?

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Input Nirvana

13 Oct 2012, 07:28

I don't come to the conclusion they are more cost effective. If anything I'm hoping they are the same cost. The pcb is considerably larger which isn't a problem with the Kinesis. I'm mostly looking for another reliable source. Good drivers are a plus, but I personally use Mac, so I'm thinking of others with regards to the drivers.

I might be making it a bit harder than necessary, but I'm thinking ahead and trying to get a few options available. Someone else has finally put a pointing stick in a Kinesis and I think several people might do it to Maltrons. It's a natural fit, even if you don't care for Trackpoints.

I think there may be a way to purchase pointing sticks from someone....I've seen it in Keyboardmods.com but have not gotten ahold of the guy. (I'm "GG" in the comments section)

User avatar
wcass

13 Oct 2012, 17:10

i harvested a trackpoint from an old IBM laptop i was disposing. i know i will never use it, but thought that someone from the community might. if you would like it, send me a PM.

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Input Nirvana

13 Oct 2012, 19:31

LOOK!!!!

I think it has it's own pcb like the KPD8923...this helps.

Any help or info on what this part is from the IBM Thinkpad...

Translation would be the bomb!

http://alpha.mixi.co.jp/2011/10803/

User avatar
Icarium

14 Oct 2012, 13:16

As mentioned here ( http://deskthority.net/workshop-f7/dail ... trackpoint ) many Thinkpads have the trackpoint on another PCB. Not all of them though but there are so many of those keyboards on ebay for cheap that trying works decently.

The more annoying part is to find a nice piece of plastic to glue to them. :)

User avatar
wcass

15 Oct 2012, 20:03

free to good home:
Trackpoint.jpg
Trackpoint.jpg (177.16 KiB) Viewed 8359 times
Trackpoint 001.jpg
Trackpoint 001.jpg (195.91 KiB) Viewed 8359 times

User avatar
Input Nirvana

15 Oct 2012, 20:18

So 4 of the 10 contacts the ribbon connects to, are the 4 usb wires (or ps/2). Those would be the only connections needed.

Am I seeing/understanding this correctly?

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wcass

15 Oct 2012, 23:30

input nirvana wrote:So 4 of the 10 contacts the ribbon connects to, are the 4 usb wires (or ps/2). Those would be the only connections needed.

Am I seeing/understanding this correctly?
yes, i believe that 4 of these are PS2.

User avatar
Input Nirvana

15 Oct 2012, 23:43

We're both in the US, so if no one else is all over that thing, I'll spot a few dollars to you for that homeless waif. I need another Trackpoint for the second Kinesis.

I can photo it, catalog some info, and add a sub-header to the Kinesis wiki, which should be a fairly helpful bit of info that will continue to get passed along. If course the wiki won't be rebuilt till the holidays I'm sure.

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Input Nirvana

23 Oct 2012, 02:13

Wcass sent me the trackpoint shown above from an IBM G40.....2388-BBG (Thank you!)

At some point, I'll find the pinouts, maybe test with a meter, solder intermediate connecting wires directly to the pcb, and then to a passive ps/2>usb adapter which will connect to a 4 port usb hub located in the Kinesis. Locate the 3 button connections (I know each button has 2 wires...the buttons must just be contact switches). The other 4 wires are the ps/2 connections.

Of course, that's assuming Mac OSX will have no issues with it, just like the trackpoint from the KPD8923 is problem-free.

Icarium: Now that I'm holding the tiny thing in my hand, you're right, cementing the extended post will be a bit of a challenge if nothing else than other due to the very small size. It's all about the glue.

User avatar
wcass

23 Oct 2012, 03:35

Icarium, would you share the pin assignments from the trackpoint that you worked on? they might be the same.

User avatar
Input Nirvana

23 Oct 2012, 04:37

Looks like a PTPM754DB just like in Icariums datasheet link...not that I'm familiar...I'm not an electronics guy.
So according to some schematics, I'm thinking this is a Trackpoint IV, with firmware 3E.
I noted on Icariums photos, he had 7 wires (4 for the ps/2 and only 3 for the buttons, not 6 for in/out buttons?)

So maybe the 10 contacts to the ribbon are the same?
Attachments
wcass trackpoint.JPG
wcass trackpoint.JPG (124.67 KiB) Viewed 8297 times

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Icarium

23 Oct 2012, 12:01

Uhm...so do you need any specific information? I don't remember much of the top of my head but could check my scribblings. :)

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suka
frobiac

23 Oct 2012, 12:34

In case you want to cross-check, I have two other trackpoints documented in my DIY project that use the same chip.

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Input Nirvana

23 Oct 2012, 15:50

Thanks you guys...looks to be very similar. I've taken a look at the data sheets and the links to posts and pics. I feel confident that the pinouts may be the same. I already figured the 2 middle pins were for power and ground since they had the larger traces...and that matches your pinouts. I don't think I can go wrong as long as I have power and ground.

So for the 3 buttons,there is a wire going to each contact switch, then the other side of the switch goes to any ground, correct?

What is the 'reset' for, and what will it be connected to?

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uberben

29 Nov 2012, 16:00

Have you looked on AliExpress? They sell replacement laptop keyboards with TrackPoint modules for between $15 and $50 (ThinkPad keyboards are towards the upper end, but you can get a Dell or HP at the lower end): http://www.aliexpress.com/wholesale?Sea ... 0&manual=y

I don't like the idea of buying a brand new keyboard just to harvest out a tiny part and throw out the rest. Maybe you could contact the seller and see if they would be willing to sell some TrackPoints on their own. AliExpress, to my knowledge, is like a store for the manufacturers, you are skipping all middle men, so asking for just the Trackpoints just might work. In that case, they might have a minimum quantity, so maybe a group buy would be needed.

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uberben

29 Nov 2012, 17:43

This mouse looks interesting too, though it seems like the TrackPoint might just be for scrolling (they refer to it as a ScrollPoint): http://shop.lenovo.com/us/itemdetails/3 ... 1FC42C9CA3

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