Author Topic: XT/AT/PS2/Terminal to USB Converter with NKRO  (Read 893915 times)

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Offline fohat.digs

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #950 on: Tue, 29 October 2013, 07:38:29 »
There's a solder resist layer, so it shouldn't have directly shorted anything, and lines in parallel have some capacitance between them anyway.

Several hours on, and 2 reboots with no problem.

The solder resist layer looks to be intact, and clearly the problem could have been something else altogether.

As always, I appreciate your help and advice.
"It turns out that for a decade, whenever Trump wanted to get a loan, or make a deal, he would inflate the value of his real estate. For instance, suggesting that his 11,000-square foot penthouse was a 30,000-square foot penthouse.
And the attorney general of New York knew that Trump's property values were inflated because when it came time to pay taxes, Trump undervalued the very same properties.
It was all part of a very sophisticated real estate practice known as “lying.”
- Jon Stewart 2024-03-28

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #951 on: Tue, 29 October 2013, 19:25:42 »
Well that's good news! I wouldn't have thought it was that sensitive... next time I have one apart I'll try putting a hammer or two on some of those traces to see if it affects it.

Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #952 on: Mon, 04 November 2013, 03:43:39 »
Trying to rig up an external one, this is the most I get. Nothing happens if I hit a key, and only get R05 if I unplug or plug into the adapter.

Trollbogey:configs hellmark$ ~/Downloads/hid_listen.mac
Waiting for device:...
Listening:
wEE

remaining: 0051
2C@0008 remaps
05@0034 layers
20@0039 remaps
layerdefs: 01
max_layer: 01
total_macros: 00
alloc ok.


Keyboard ID: 0000
Code Set: 1
Mode: PC/XT

R05

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #953 on: Mon, 04 November 2013, 06:33:08 »
I think that's what you'd get if the clock line was permanently low, and always being read as 0. A few things could cause that (roughly in order of likelihood): either +5V isn't connected to the keyboard, or clock is shorted to ground, or there's an internal fault in the keyboard, or possibly the Teensy pin has been damaged by shorting it with +5V at some point (actually, I'm not sure exactly how a failure affects it in that case; it might always read as '1'). A multimeter would help a lot in checking the first two!

Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #954 on: Mon, 04 November 2013, 11:03:56 »
I soldered ground to the VCC and Ground near the reset switch. I do notice that most people tend to connect to the one up near the USB jack. Is there a difference that would be causing this?

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #955 on: Mon, 04 November 2013, 14:51:26 »
No, no difference between the two GND pads (or between the two VCC pads).

So, any chance that one of the possibilities above might be the problem? Could you post a pic in case there's some problem we might spot?

Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #956 on: Mon, 04 November 2013, 14:58:19 »
I am at work right now. Last night after I made the post, I unsoldered everything and soldered on pins before going to bed. When I get home, I'll attempt again, and double checking everything with my multimeter.

Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #957 on: Tue, 05 November 2013, 07:12:25 »
Taking a look at it now. 4.94V reading at the pins. Not seeing any sign of a short for the clock. Tried with another keyboard I know works, and still get the same thing for ID 0000, and R05.

Just to double check, the pinout that you have on the first post is for the female connector, right? That's how I read it as.
« Last Edit: Tue, 05 November 2013, 07:14:05 by Hellmark »

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #958 on: Tue, 05 November 2013, 07:49:39 »
The front of the female connector, yup. The docs have a diagram from the IBM techref that makes it clearer.

Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #959 on: Tue, 05 November 2013, 07:53:21 »
Damn, I was hoping that I misread it and wired it up backwards.

Would you say that it seems likely then that the teensy is damaged? What would I need to do to get it going with other pins for clock and data? I know your source isn't available, and often that sorta thing is hard coded.

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #960 on: Tue, 05 November 2013, 08:05:12 »
With no keyboard attached, does it still do the single R05 thing, but the PD1 pin is at roughly 5V?

edit: I just tried shorting clock to ground, and it does give this behaviour as I thought. There could be other ways, of course!

edit2a: Last time this problem came up was when Harry incorrectly wired a pull-up resistor (so it was pulling down, presumably).

edit2b: In case the Teensy is damaged, there is an alternate hex for atmega32u4 which uses different pins.
« Last Edit: Tue, 05 November 2013, 08:24:03 by Soarer »

Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #961 on: Tue, 05 November 2013, 08:31:51 »
no keyboard attached, no R05. I am running without pull up resistors, could lack of pull ups cause this?

Using the alternate pins and firmware, same result.
« Last Edit: Tue, 05 November 2013, 08:44:02 by Hellmark »

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #962 on: Tue, 05 November 2013, 09:09:10 »
Pull-ups are usually not required, and if they were it wouldn't give this kind of error.

So it doesn't seem like a damaged Teensy then,  the keyboard must be pulling it down. Still might be possible that wiring is wrong on your socket, but the next thing to test is resistance between pins on the keyboard (with it unplugged)...

ground to 5V - should a few kohm
data to 5v - should be 1 or 2 kohm (for a PC/XT, maybe higher for others)
clock to 5v - should be 1 or 2 kohm (for a PC/XT, maybe higher for others)
ground to clock - should be higher than ground to 5V, by 1 or 2 kohm
ground to data - should be higher than ground to 5V, by 1 or 2 kohm
might as well test data to clock as well!

What keyboard is it?

Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #963 on: Tue, 05 November 2013, 12:18:48 »
I have a XT model F (what I primarily want it for), and also tried with a AT NMB keyboard. Same results on both. I'll try do some more probing tonight.

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #964 on: Tue, 05 November 2013, 14:52:49 »
Actually, same on both would indicate something wrong with the wiring of the socket. Please quadruple check that it's not mirrored! If the 5V to the keyboard is actually GND, it will pull both clock and data low, and give that single R05 symptom. If, at the same time, the GND to the keyboard is actually 5V, that can easily damage the power smoothing capacitors (on the XT at least. Easy enough to replace though).

Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #965 on: Tue, 05 November 2013, 16:29:40 »
I'll check again tonight. I cut the female end of an AT adapter off, and out of that was 5 wires. Brown, Red, Black, and Orange, with the final one being bare. The bare one is what I've been treating as ground, because when I tested things initially it is what thought was ground, plus usually when ever I see bare in a bundle like that, it is the ground. When I tested things, I had been up for about 24 hours straight, so possible I poked the wrong spot with something.

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #966 on: Tue, 05 November 2013, 16:38:00 »
Ah, the bare one will be the case ground. One of the others needs to be connected to ground for it to operate (as well as the case ground if you like, but the case ground is optional). BUT I'm not sure whether that error alone would produce the same symptom, so check 'em all!

Offline vivalarevolución

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #967 on: Tue, 05 November 2013, 20:16:33 »
Great news!  After weeks of reading up on this thread, Soarer's documentation and such, I finally decided to take the dive and see if I could get my F122 to work with the converter using the materials that I have on hand.

So I stripped one end of the female-to-female breadboard wires and attached those to a socket.
Then I attached the intact female end of the breadboard wire to the Teensy.
I loaded the files onto the Teensy.
I then plugged the keyboard into the socket, restarted the computer, and everything seems to work alright. 

Typing on the F122 right now!  Was not nearly as difficult as I built it up in my head.

It looks pretty ugly and is an admittedly awful, temporary build, but I just wanted to see if I could get this thing to work.  And it does.

However, I still have some issues with getting the computer to consistently read the keyboard on restart or re-insertion of the converter.  I will describe those in more detail if they persist with a more solid build.
« Last Edit: Tue, 05 November 2013, 20:56:21 by prdlm2009 »
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Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #968 on: Wed, 06 November 2013, 00:35:28 »
Ok, I went through and double checked things. One wire I did have off. I before thought it was reset, but apparently there isnt' a wire to the reset, and instead is ground. I have both the bare wire ground ground and the pin ground now connected to the teensy's ground. The other ones seem to be correct though. Female plug facing me. from left to right, I have clock, ground, data, VCC, and what should be 3 but is no wire. That should match up with what the diagram shows.

Offline vivalarevolución

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #969 on: Wed, 06 November 2013, 05:53:49 »
Ok, I connected the breadboard female-to-female wires to the controller and I plan to directly contact those to the Teensy.  I am wondering if there is a way to determine the connection of each wire without using a multimeter, which seems to be the preferred method in this thread.  I know that others have documented this before, but I also know we cannot rely on the color of connection wires being consistent between models.

FYI, I have an F122, model #6110347.

EDIT:  Nevermind folks.  I searched the thread and found fohat's earlier fumbles with an F122 from two years ago, and I have this thing working fine with a direct connection to the controller without any soldering.

My only question is how permanent of a solution is the solderless converter?  I plan to keep the teensy in the case, but I have some concerns about the pins on the pre-soldered Teensy getting bent.
« Last Edit: Wed, 06 November 2013, 06:34:27 by prdlm2009 »
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Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #970 on: Wed, 06 November 2013, 06:28:34 »
Without a multimeter, may be a bit tricky. Luckily multimeters are cheap. Harbor Freight is in most areas and has them for $5. Quite a few different tool stores should have cheap no frills ones. Amazon also has a number of cheap ones in the $5 range.


Offline vivalarevolución

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #971 on: Wed, 06 November 2013, 06:37:02 »
Without a multimeter, may be a bit tricky. Luckily multimeters are cheap. Harbor Freight is in most areas and has them for $5. Quite a few different tool stores should have cheap no frills ones. Amazon also has a number of cheap ones in the $5 range.

Thanks.  I was able to figure things out looking at some older posts.  Now my only concern is the permanency of my current solution without soldering.
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Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #972 on: Wed, 06 November 2013, 06:52:15 »
Without soldering, it won't be permanent. Pick up a cheap iron go to town. Making stuff is fun, and a skillset so many people are missing any more.

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #973 on: Wed, 06 November 2013, 07:02:09 »
Good. Yes, if you've found the pinout of the connector on the controller, you can rely on that.

The key thing to the connections staying put is to stop the cable pulling on it - solve that and you're most of the way there. Then wrap the Teensy in something (foam?) or stick it down, and it should be fine for a good time. It's also improtant that the Teensy pins don't short to ground (e.g. the case!), especially pin PD6 since that's +5V when the LED is lit (also, since that's on the end, it's more likely to touch).

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #974 on: Wed, 06 November 2013, 07:09:18 »
Ok, I went through and double checked things. One wire I did have off. I before thought it was reset, but apparently there isnt' a wire to the reset, and instead is ground. I have both the bare wire ground ground and the pin ground now connected to the teensy's ground. The other ones seem to be correct though. Female plug facing me. from left to right, I have clock, ground, data, VCC, and what should be 3 but is no wire. That should match up with what the diagram shows.

Right, that sounds good. I still can't think how the missing ground gave the symptom, so it's worth checking at least the 5V to GND resistance on the XT keyboard in case it's damaged somehow. Otherwise, time to see what happens when it's plugged in...

Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #975 on: Wed, 06 November 2013, 09:23:43 »
Same results, no change on either the AT or XT.

1.3kOhm on the XT for ground to 5v. Data and clock to 5v are both 2kOhm. Data and clock to ground are both around 3.25kOhm. Data to clock is 4kOhm.

AT keyboard is 9.6 ground to 5v. 11.8kOhm data and clock to ground. Data to 5v is 2kOhm, clock is 2kOhm. 4.38kOhm data to clock.

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #976 on: Wed, 06 November 2013, 11:02:14 »
Those readings are all good. I'm stumped for the moment! Can't see how the clock line gets grounded, but only when a keyboard is plugged in, yet the keyboards seem fine.

In case I'm making an incorrect assumption, can you measure the voltage on the clock line when a keyboard is attached?

Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #977 on: Wed, 06 November 2013, 11:15:33 »
The AT keyboard I know is good, because I was using it before I unplugged it to test it with the teensy. I am wondering if I did something to dork up the plug, and didn't realize it, because I know it was all good to start with, since I used it with the AT keyboard to work on a PS/2 system before I started.

Yeah, I can test voltage tonight, shouldn't be a problem.

Offline vivalarevolución

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #978 on: Wed, 06 November 2013, 14:17:26 »
Without soldering, it won't be permanent. Pick up a cheap iron go to town. Making stuff is fun, and a skillset so many people are missing any more.

I do have a solder iron and I cannot wait to play with it!  But I'm a little cautious of screwing up the keyboard or Teensy with my novice soldering skills.  On the bright side, this converter has reawakened my dormant DIY and tinkering tendencies.

Good. Yes, if you've found the pinout of the connector on the controller, you can rely on that.

The key thing to the connections staying put is to stop the cable pulling on it - solve that and you're most of the way there. Then wrap the Teensy in something (foam?) or stick it down, and it should be fine for a good time. It's also improtant that the Teensy pins don't short to ground (e.g. the case!), especially pin PD6 since that's +5V when the LED is lit (also, since that's on the end, it's more likely to touch).

Luckily, these Model F's have a clamp of sorts that will keep that USB cable in place.  What is the purpose of wrapping the Teensy in foam?
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Offline fohat.digs

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #979 on: Wed, 06 November 2013, 14:24:36 »
What is the purpose of wrapping the Teensy in foam?

If you put it internal there are lots of metal surfaces that could touch any number of points and short them.

There is an extra bracket that I attach to if I am using a breadboard.
"It turns out that for a decade, whenever Trump wanted to get a loan, or make a deal, he would inflate the value of his real estate. For instance, suggesting that his 11,000-square foot penthouse was a 30,000-square foot penthouse.
And the attorney general of New York knew that Trump's property values were inflated because when it came time to pay taxes, Trump undervalued the very same properties.
It was all part of a very sophisticated real estate practice known as “lying.”
- Jon Stewart 2024-03-28

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #980 on: Wed, 06 November 2013, 16:06:18 »
Yeah, and foam would stop it rattling around, which might also be enough to prevent cables falling out. I'm thinking enough foam so the foam is squashed by the case when closed ;)

Offline vivalarevolución

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #981 on: Wed, 06 November 2013, 16:24:36 »
Thanks guys.  I'm a technological Luddite that forgot everything I learned from my Electronics merit badge.
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Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #982 on: Thu, 07 November 2013, 06:40:12 »
with AT keyboard attached, 2.28V on clock line. XT it is 2.84V.

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #983 on: Thu, 07 November 2013, 06:51:25 »
Interesting. I wonder if the 5V is connecting to the keyboard properly. I'd guess at similar voltages on the data line in that case.

Does the AT have LEDs, and do they flash on as they should when it's connected?

Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #984 on: Thu, 07 November 2013, 07:27:05 »
AT has LEDs, and they do not flash. Not even a flicker.

On data line, reading .69V when keyboard is plugged in.

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #985 on: Thu, 07 November 2013, 14:04:33 »
Time to test continuity all the way through then. Easiest with the XT because I can show you where to probe, and there's handy test pads as well! You'll need to open it up and connect it to the converter (but not plug the USB side in), then check resistance between these points and the corresponding pins on the Teensy - they should all be 'low', as in ohms or tens of ohms.

43082-0

Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #986 on: Thu, 07 November 2013, 23:57:31 »
I used the test pad as marked out by you in that pic. For the following I go from the test pad to the pin on the teensy. Keyboard plugged in, but USB isn't plugged in.
XT Test Point to teensy pin:
Ground to VCC = 1.25kOhm
Ground to Clock = 3.25kOhm
Ground to Data = 3.25kOhm
Ground to ground = 1.1kOhm

VCC to Clock = 2.02kOhm
VCC to Data = 2.03kOhm
VCC to Ground = 1.238kOhm
VCC to VCC = 1.1kOhm

Data to Clock = 4.03kOhm
Data to Ground = 3.28kOhm
Data to VCC = 2.03kOhm
Data to Data = 1.2kOhm

Clock to Data = 4.05kOhm
Clock to Ground = 3.26kOhm
Clock to VCC = 2.015kOhm
Clock to clock = 1.1kOhm

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #987 on: Fri, 08 November 2013, 07:05:34 »
They all seem as expected, except for these:

Ground to ground = 1.1kOhm
VCC to VCC = 1.1kOhm
Data to Data = 1.2kOhm
Clock to clock = 1.1kOhm

Which I think is just a mistake in writing them - they should be without the 'k' - since the other measurements wouldn't be as they are, otherwise.

Next test is to plug the USB in, and measure the Vcc, Data and Clock voltages on those test pads, using the GND test pad as reference ('reference' just means where you stick the black probe).

Surely we must find something wrong soon!  :'(

Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #988 on: Fri, 08 November 2013, 12:31:33 »
Oops, do believe that was a copy paste problem.

I'll double check voltages when I get home. I am hoping we can find something soon too, and thank you for being so patient.

Offline fohat.digs

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #989 on: Fri, 08 November 2013, 19:19:36 »
I forgot to report back on my mysterious problem with spurious key strokes. No problem any more after at least a week of constant use (although my USB port must be weird, every few days or weeks it stops working (and knocks out other USB ports, too) until I unplug it and hot plug it again).

Soarer was skeptical that the metallic paint was the problem, and I did completely disassemble and reassemble it, so various things could have been jiggled just a bit.

Another thing - I have 3 bolts added in the concave part of the plate: approximately between 5 and upper F5, between 0 and upper F10, and between Enter and Up Arrow. I feel that these tighten up the feel somewhat, since the F-122 has such a vast unsupported area down the center line (those tabs hardly touch).

In the earlier iteration, I had these torqued down fairly hard, perhaps too hard. Afterwards, I made them just a hair past "snug"

Perhaps I was simply pulling the plates too close together and getting near contact with the hammers.
"It turns out that for a decade, whenever Trump wanted to get a loan, or make a deal, he would inflate the value of his real estate. For instance, suggesting that his 11,000-square foot penthouse was a 30,000-square foot penthouse.
And the attorney general of New York knew that Trump's property values were inflated because when it came time to pay taxes, Trump undervalued the very same properties.
It was all part of a very sophisticated real estate practice known as “lying.”
- Jon Stewart 2024-03-28

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #990 on: Sat, 09 November 2013, 14:15:58 »
That sounds quite plausible :D

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #991 on: Sat, 09 November 2013, 21:59:25 »
with AT keyboard attached, 2.28V on clock line. XT it is 2.84V.

AT has LEDs, and they do not flash. Not even a flicker.

On data line, reading .69V when keyboard is plugged in.

I tried a few tests, and the closest I got to these voltages was 0.5V on both clock and data, when the +5V line was disconnected from the keyboard. When the +5V from the keyboard was connected to GND on the Teensy, both were even lower, about 0.27V. I'm not prepared to try connecting the keyboard's power in reverse, but, assuming it didn't emit smoke, I'd expect a similar 0.27V or thereabouts.

I can't think how to get anything like 2.2 to 2.8V with the various resistances available  - the pull-up within the Teensy is very roughly 25kOhm, so it would require something similar to that pulling down. The other option would be that it is constantly flitting between 0V and 5v (and the multimeter averages it), but then the converter should be putting out more error messages.

Also, I don't know why there's the difference between data and clock voltages, on yours.

Hmm  :confused:

Offline Hellmark

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  • Location: Maryland Heights, Mo, USA
Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #992 on: Sun, 10 November 2013, 00:37:14 »
Right now, I am kinda tempted to bypass the connector, and solder directly to the test pads, and see how it goes. I really wonder if i dorked up the plug.

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #993 on: Sun, 10 November 2013, 05:18:07 »
I dunno - measuring the resistances from the test pads to the Teensy seemed to show that the connector is fine.

What's the voltage at the Vcc test pad?

Offline Hellmark

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #994 on: Mon, 11 November 2013, 07:39:02 »
VCC test pad to Ground test pad = 1.529V
Ground to data = 110mV
ground to clock (black on ground) = -1.257V

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #995 on: Mon, 11 November 2013, 08:17:56 »
Well that's clearly not the voltages we want there! They would account for the single R05 symptom, so we're getting somewhere :)

It doesn't correlate at all with the resistances between the test pads and the Teensy though (reply 986) - if those were correct, there's no way we could see a -ve voltage on clock w.r.t. ground. In fact, the only way we'd see a -ve voltage anywhere w.r.t. ground is if ground wasn't wired to ground! (Which would probably also mean that at least one other wire isn't wired correctly).

Just to verify - when you measured the resistances, was it all the way from the test pads to the Teensy pins and not just between the test pads and the keyboard's controller or cable connector?

A photo of your Teensy wiring would be really helpful in case there's something visibly wrong!

Offline Hellmark

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  • Location: Maryland Heights, Mo, USA
Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #996 on: Mon, 11 November 2013, 08:48:34 »
When I tested resistance, I tested black on test pad to red on pins on the teensy. Wanted to make sure things went between the adapter and the cable.

Attached are how things are looking right now.

The pink looking thing is a bit of shrink tubing to help make sure that nothing shorted out on the case ground.

Offline Soarer

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Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #997 on: Mon, 11 November 2013, 09:10:40 »
That look OK.

So with everything plugged in, what's the voltage on the Teensy Vcc w.r.t ground? (I've been assuming that it's still 5V as it should be, since the Teensy appears to be running, and the USB port would probably have shut down otherwise).

Offline Hellmark

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  • Location: Maryland Heights, Mo, USA
Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #998 on: Wed, 13 November 2013, 07:33:39 »
Ground test pad to VCC pin on teensy, VCC test pad to ground pin on teensy, test pad to test pad, and pin to pin, doesn't matter, all register at 1.5V.

For ****s and grins, I tried going off the other ground and VCC pins on the teensy, and all works now!

Just to let you know that this works, I am typing this from the XT now, and will be taking it with me to work.

I really forgot about the different thwack sound of the F verses the M. Really been a long time since I had a chance to use one of these. I am really happy considering that I will be having some marathon sessions at work this week because of the final portion of the data center migration, so I am happy that I have this keyboard going. Right now on OSX, so no arrow keys since I cannot disable the numlock, but oh well. I have the keyboard working and that is what matters. That's a problem of the OS and not the keyboard or convertor, and could be overcome with changing the key mapping if I really want to, but probably won't monkey with since this is going to be used on Linux and Windows.
« Last Edit: Wed, 13 November 2013, 11:50:55 by Hellmark »

Offline Hellmark

  • Posts: 349
  • Location: Maryland Heights, Mo, USA
Re: XT/AT/PS2/Terminal to USB Converter with NKRO
« Reply #999 on: Wed, 13 November 2013, 07:39:06 »
Ok, after bringing it in to work with me, I realized that I definitely need to tweak the keymapping. The function keys are mapped to other things like media control, and for my work, I really need the function keys. Guess next step is to try and figure that out.
« Last Edit: Wed, 13 November 2013, 11:53:57 by Hellmark »