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Help adapting the NCR 4950

Posted: 13 Jul 2018, 04:56
by consideringquiet
I recently came into owning this keyboard in pretty great condition, and was hoping to find someone who had previously adapted it to USB before. Unfortunately after searching awhile I wasn't so lucky. If anyone has any knowledge on this board I'd greatly appreciate it. I'll be posting a picture of the pinout tomorrow morning.

Posted: 13 Jul 2018, 15:25
by Blaise170
There's no need to pin it out, it's standard AT protocol. All you need is a DIN-5 to PS/2 converter (and a PS/2 to USB converter if you can't use PS/2). Alternatively if you want to remap keys you can buy a pre-converted cable from Orihalcon that converts straight from DIN-5 to USB.

Posted: 13 Jul 2018, 15:28
by mike52787
Blaise170 wrote: There's no need to pin it out, it's standard AT protocol. All you need is a DIN-5 to PS/2 converter (and a PS/2 to USB converter if you can't use PS/2). Alternatively if you want to remap keys you can buy a pre-converted cable from Orihalcon that converts straight from DIN-5 to USB.
no? pretty sure this board has a RJ12 jack and some alien protocol. I had one, but never tried to convert it.

Posted: 13 Jul 2018, 15:40
by Blaise170
Ooh I misunderstood the wiki. Looks like if you desolder the RJ-11 cable and replace it with a DIN-5 or PS/2 cable that it should work as long as it has AT switching on the board.

Posted: 13 Jul 2018, 16:05
by consideringquiet
Blaise170 wrote: Ooh I misunderstood the wiki. Looks like if you desolder the RJ-11 cable and replace it with a DIN-5 or PS/2 cable that it should work as long as it has AT switching on the board.
So just stripping a USB and soldering it to the respective pinouy should work?

Posted: 13 Jul 2018, 16:12
by mike52787
consideringquiet wrote:
Blaise170 wrote: Ooh I misunderstood the wiki. Looks like if you desolder the RJ-11 cable and replace it with a DIN-5 or PS/2 cable that it should work as long as it has AT switching on the board.
So just stripping a USB and soldering it to the respective pinouy should work?
absolutely not.

Posted: 13 Jul 2018, 17:18
by Blaise170
USB is not directly compatible with AT protocol. PS/2 is compatible with AT and there are plenty of PS/2 to USB converters on the market though (and again, only if it has XT/AT switching on the mainboard since it appears that these used two protocols depending on manufacturing date).

Posted: 13 Jul 2018, 18:16
by consideringquiet
Blaise170 wrote: USB is not directly compatible with AT protocol. PS/2 is compatible with AT and there are plenty of PS/2 to USB converters on the market though (and again, only if it has XT/AT switching on the mainboard since it appears that these used two protocols depending on manufacturing date).
Oh okay, I wouldn't mind just using ps2 anyhow :)

Posted: 13 Jul 2018, 21:28
by consideringquiet
Blaise170 wrote: USB is not directly compatible with AT protocol. PS/2 is compatible with AT and there are plenty of PS/2 to USB converters on the market though (and again, only if it has XT/AT switching on the mainboard since it appears that these used two protocols depending on manufacturing date).
So, how would I deciper what colored wires are what on PS2? I got my cable from a Dell Quietkey so I am not sure how standard that cable is in terms of colors and ground wires (the ground in this case is a screw in).

Posted: 13 Jul 2018, 21:34
by Blaise170
I'm not that good with wiring - you'd need to ask someone else. Were you able to verify whether this is ADDS or XT/AT protocol?

Posted: 13 Jul 2018, 21:36
by consideringquiet
Blaise170 wrote: I'm not that good with wiring - you'd need to ask someone else. Were you able to verify whether this is ADDS or XT/AT protocol?
Well unfortunately no, I'm not entirely certain how to check that. Here's a photo

Posted: 13 Jul 2018, 22:34
by consideringquiet
So I took some extra photos. The ps2 cable I wanted to use is from a Dell quietkey. I spoke to a redditor on this and he gave me a pinout. He said he knew how to adapt my particular version and would tell me for a price. Anywho, attached are some photos I took. I have a cu on the ps2 jerry rigged in at some point. Don't want to plug in random configs for fear of frying

Posted: 13 Jul 2018, 22:48
by snacksthecat
consideringquiet wrote: So I took some extra photos. The ps2 cable I wanted to use is from a Dell quietkey. I spoke to a redditor on this and he gave me a pinout. He said he knew how to adapt my particular version and would tell me for a price. Anywho, attached are some photos I took. I have a cu on the ps2 jerry rigged in at some point. Don't want to plug in random configs for fear of frying
Seeing that voltage regulator makes me think maybe this isn't a 5V board. Do you have a multimeter to test?

Posted: 13 Jul 2018, 22:52
by snacksthecat
By the way, this reminds me very much of another terminal board that I worked on a couple months back.

workshop-f7/link-alloy-cherry-g80-0693- ... 18643.html

Posted: 13 Jul 2018, 22:55
by consideringquiet
snacksthecat wrote:
consideringquiet wrote: So I took some extra photos. The ps2 cable I wanted to use is from a Dell quietkey. I spoke to a redditor on this and he gave me a pinout. He said he knew how to adapt my particular version and would tell me for a price. Anywho, attached are some photos I took. I have a cu on the ps2 jerry rigged in at some point. Don't want to plug in random configs for fear of frying
Seeing that voltage regulator makes me think maybe this isn't a 5V board. Do you have a multimeter to test?
I do not :/

Posted: 13 Jul 2018, 23:09
by snacksthecat
I'm going to guess that it was built expecting 12V but also may work with 9V. If you share some pictures of the reverse side of the PCB (the one where you can see all the traces), someone should be able to confirm if that guy gave you the right pinout.

The first thing you want to figure out is which line is Gnd and Vcc

Then figure out what voltage it requires. Since you don't have a multimeter, one hint might be whether the lights come on when hooked up to 5V, or whether they stay dark (or some in between dim).

Then we need to figure out which are the signal line(s) (e.g. data/clock or serial)

Finally figure out what protocol it uses.

When you put it all together you get a nice little game plan.

For the record, I really do have a hunch that this board would work with my converter I made. Both boards were RJ-11, manufactured by NMB, and had similar voltage regulators.

Posted: 14 Jul 2018, 00:21
by TheInverseKey
I have some information to add to this since the adds2020 is close adds1010 that I am currently working to reverse engineer. Here is the datasheet for the IC.

Datasheet: https://www.datasheets360.com/pdf/-6219928323035552889


Edit:
Opps frogot to mention the colors and what they mean on the original cable since they can vary from board to board.

Black: GND
Green: N/A
Red: N/A
Yellow: VCC

I will be working on this for the next couple of weeks hopefully.

Edit2:
Back of the adds1010 controller
Image

Posted: 14 Jul 2018, 00:49
by TheInverseKey
consideringquiet wrote: So I took some extra photos. The ps2 cable I wanted to use is from a Dell quietkey. I spoke to a redditor on this and he gave me a pinout. He said he knew how to adapt my particular version and would tell me for a price. Anywho, attached are some photos I took. I have a cu on the ps2 jerry rigged in at some point. Don't want to plug in random configs for fear of frying

There should also be some parts of that board with some connections that are missing and have the following letter combo:

JUP

This is for the jumpers and I think last time I checked they were on the right side of the board on the front facing up. If you can post a picture of the whole top of the PCB then I can help you out more.

Posted: 14 Jul 2018, 02:50
by consideringquiet
TheInverseKey wrote:
consideringquiet wrote: So I took some extra photos. The ps2 cable I wanted to use is from a Dell quietkey. I spoke to a redditor on this and he gave me a pinout. He said he knew how to adapt my particular version and would tell me for a price. Anywho, attached are some photos I took. I have a cu on the ps2 jerry rigged in at some point. Don't want to plug in random configs for fear of frying

There should also be some parts of that board with some connections that are missing and have the following letter combo:

JUP

This is for the jumpers and I think last time I checked they were on the right side of the board on the front facing up. If you can post a picture of the whole top of the PCB then I can help you out more.
Heres some photos, sorry for iffy camera quality.

Posted: 14 Jul 2018, 03:11
by TheInverseKey
Here is a photo of the jumpers that need to be added so that it can be converted. They are the ones that have been done in copper wire that doesn't have a silver plating on them.

Image

Posted: 14 Jul 2018, 16:21
by consideringquiet
TheInverseKey wrote: Here is a photo of the jumpers that need to be added so that it can be converted. They are the ones that have been done in copper wire that doesn't have a silver plating on them.

Image
So just clip the JA jumpers and solder those two JP jumpers together?

Posted: 15 Jul 2018, 18:09
by TheInverseKey
Don't clip the the other jumpers and you should only solder the new ones on.

Posted: 15 Jul 2018, 18:27
by consideringquiet
TheInverseKey wrote: Don't clip the the other jumpers and you should only solder the new ones on.
Oh so just leave the JA jumps? I'll make sure not to. Any tips on getting the wires to stay put while soldering? Just pray?

Posted: 15 Jul 2018, 18:34
by snacksthecat
consideringquiet wrote:
TheInverseKey wrote: Don't clip the the other jumpers and you should only solder the new ones on.
Oh so just leave the JA jumps?
For my own needs; what is filling these links supposed to enable?

Posted: 15 Jul 2018, 18:38
by Compgeke
consideringquiet wrote: Heres some photos, sorry for iffy camera quality.
There's a 7805 in the middle of those pics which is going to throw a wrench into easy PS/2 conversion. It's not going to work without at least 7V input, of which PS/2 only provides 5. Unless modifying the jumpers will bypass the voltage regulation section, you won't get any signs of life from the board on PS/2.

Posted: 15 Jul 2018, 18:47
by consideringquiet
snacksthecat wrote:
consideringquiet wrote:
TheInverseKey wrote: Don't clip the the other jumpers and you should only solder the new ones on.
Oh so just leave the JA jumps?
For my own needs; what is filling these links supposed to enable?
From my understanding it enables the AT protocol on the board.
Compgeke wrote:
consideringquiet wrote: Heres some photos, sorry for iffy camera quality.
There's a 7805 in the middle of those pics which is going to throw a wrench into easy PS/2 conversion. It's not going to work without at least 7V input, of which PS/2 only provides 5. Unless modifying the jumpers will bypass the voltage regulation section, you won't get any signs of life from the board on PS/2.
Seems like it. I wired up the board to a PS2 cable, I haven't done the jumpers yet. But whenever I plugged it in to see if I'd get any lights, I got zip. Of course, it could also be my awful solder job but I digress.

Heres the mess I made:

Posted: 15 Jul 2018, 18:59
by Compgeke
Quick tip on soldering: the chisel tip is fine (it's what I use), it's more on method. For joining the wires to pins with solder, I'd tin the wire lead, tin the pin lead then heat them together to reflow the joints into one. Same process one would use for something like soldering leads on LEDs.

When tinning the leads, apply heat from the bottom and solder from the top. This helps make sure the solder flows throughout and not just a blob on one side.

Posted: 15 Jul 2018, 19:17
by snacksthecat
consideringquiet wrote: From my understanding it enables the AT protocol on the board.
My novice advice would be to first get the power problem sorted out then move on to the protocol.

Posted: 15 Jul 2018, 19:22
by consideringquiet
Compgeke wrote: Quick tip on soldering: the chisel tip is fine (it's what I use), it's more on method. For joining the wires to pins with solder, I'd tin the wire lead, tin the pin lead then heat them together to reflow the joints into one. Same process one would use for something like soldering leads on LEDs.

When tinning the leads, apply heat from the bottom and solder from the top. This helps make sure the solder flows throughout and not just a blob on one side.
So tinning is preapplying solder right? Thanks for the advice though, I'll hopefully remember it next time I need it :)

So I put all the jumpers in, and still, nada. I think I'll definitely have to figure out the power issue.

Posted: 15 Jul 2018, 19:31
by consideringquiet
All soldered in. Now I gotta figure out this power issue. The guy I spoke to over reddit didn't mention this to adapt but I'll try to contact him again.