Welcome, Guest. Please login or register.


Author Topic: PS/2 keyboard hardware assembly (Read 5852 times)

Offline pear

  • EP lover
  • *
  • Posts: 795
  • Country: pl
  • Z80 only
  • OS:
  • Windows 7/Server 2008 R2 Windows 7/Server 2008 R2
  • Browser:
  • Firefox 44.0 Firefox 44.0
    • View Profile
Re: PS/2 keyboard hardware assembly
« Reply #15 on: 2016.February.28. 12:46:35 »
A piece of universal board should suffice.

Offline Z80System

  • EP addict
  • *
  • Posts: 3939
  • Country: hu
  • OS:
  • Windows NT 10.0 Windows NT 10.0
  • Browser:
  • Chrome 48.0.2564.116 Chrome 48.0.2564.116
    • View Profile
Re: PS/2 keyboard hardware assembly
« Reply #16 on: 2016.February.28. 14:02:54 »
Okay,

Alongside your bigger pcb idea I made some tests.


If both god and Zozosoft want that, the above EP mobo will be expanded with Saint's internal memory expansion,
so plenty of space will be released.

So I tried the spacers around the Nick. It would be good, because of the holes around the Nick are way bigger than necessary for the spacers,
so spacers can be moved approx. 2 mm in the hole, but still can be tighten. It would be good for the fix matrix universal PCB -s ...

The drawback is that Nick is pretty far from the keyboard ICs, so there would be many long wires ... not so good:
Z80 System

Offline Z80System

  • EP addict
  • *
  • Posts: 3939
  • Country: hu
  • OS:
  • Windows NT 10.0 Windows NT 10.0
  • Browser:
  • Chrome 48.0.2564.116 Chrome 48.0.2564.116
    • View Profile
Re: PS/2 keyboard hardware assembly
« Reply #17 on: 2016.February.28. 14:05:13 »
So, I tried other thing, what is closer to your idea.

In this case there will not be space for moving the spacers, because there are wires on the PCB around.

What do you think about this smaller version ? :
Z80 System

Offline pear

  • EP lover
  • *
  • Posts: 795
  • Country: pl
  • Z80 only
  • OS:
  • Windows 7/Server 2008 R2 Windows 7/Server 2008 R2
  • Browser:
  • Firefox 44.0 Firefox 44.0
    • View Profile
Re: PS/2 keyboard hardware assembly
« Reply #18 on: 2016.February.28. 14:09:36 »
If it fits, why not ? :)

Offline Z80System

  • EP addict
  • *
  • Posts: 3939
  • Country: hu
  • OS:
  • Windows NT 10.0 Windows NT 10.0
  • Browser:
  • Chrome 48.0.2564.116 Chrome 48.0.2564.116
    • View Profile
Re: PS/2 keyboard hardware assembly
« Reply #19 on: 2016.February.28. 14:43:24 »
Quote
If it fits, why not ? :)

It is not trivial, but I think, It can be done with some attention.


The PS/2 socket could be placed just next to that side where the double metal spacer will be (like in the picture),

even it can be UNDER the universal PCB (between the mobo and the universal PCB) choosing an 1.5 cm spacer height,
and the arduino micro board would (probably) fit next to the PS/2 socket.

The micro board would reach above the spacer at the edge of the mobo,
but I think with an additional lines of IC socket like these:
http://p.globalsources.com/IMAGES/PDT/B1112823448/Pitch-Single-in-Line-SIP-Socket.jpg
I can raise the micro board above the screw what will fix the universal PCB to the spacer.

The arduino micro have contacts only at the edges of the board, not in the middle.


So the height of the whole stuff would reach approx. 2.5 cm, but the PS/2 socket would be just 1-2 mm above the EP mobo, just next to the double metal spacer ...

It can be stable enough, cannot it ?
Z80 System

Offline pear

  • EP lover
  • *
  • Posts: 795
  • Country: pl
  • Z80 only
  • OS:
  • Windows 7/Server 2008 R2 Windows 7/Server 2008 R2
  • Browser:
  • Firefox 44.0 Firefox 44.0
    • View Profile
Re: PS/2 keyboard hardware assembly
« Reply #20 on: 2016.February.28. 14:49:36 »
It will definitely be a lot more stable than only on the keyboard connectors.

Offline Z80System

  • EP addict
  • *
  • Posts: 3939
  • Country: hu
  • OS:
  • Windows NT 10.0 Windows NT 10.0
  • Browser:
  • Chrome 48.0.2564.116 Chrome 48.0.2564.116
    • View Profile
Re: PS/2 keyboard hardware assembly
« Reply #21 on: 2016.February.28. 14:56:41 »
Okay, thanks for the help,

I will try to do this ...
Z80 System

Offline Z80System

  • EP addict
  • *
  • Posts: 3939
  • Country: hu
  • OS:
  • Windows NT 10.0 Windows NT 10.0
  • Browser:
  • Chrome 49.0.2623.75 Chrome 49.0.2623.75
    • View Profile
Re: PS/2 keyboard hardware assembly
« Reply #22 on: 2016.March.04. 19:31:51 »
What do you think, does the keyboard problem (for what the keyboard fixer is made) affect my arduino based keyboard interface ?

Do I have to use diodes on the wires, too ?

Or does the problem affect only the membrane keyboard ?
Z80 System

Offline pear

  • EP lover
  • *
  • Posts: 795
  • Country: pl
  • Z80 only
  • OS:
  • Windows 7/Server 2008 R2 Windows 7/Server 2008 R2
  • Browser:
  • Firefox 44.0 Firefox 44.0
    • View Profile
Re: PS/2 keyboard hardware assembly
« Reply #23 on: 2016.March.04. 19:40:35 »
I do not know. It depends on how it is constructed keyboard interface on Arduino.
If it is possible to short the two columns at the same time, the fixer may be useful (or diodes directly on the outputs from the Arduino board).

Offline Z80System

  • EP addict
  • *
  • Posts: 3939
  • Country: hu
  • OS:
  • Windows NT 10.0 Windows NT 10.0
  • Browser:
  • Chrome 49.0.2623.75 Chrome 49.0.2623.75
    • View Profile
Re: PS/2 keyboard hardware assembly
« Reply #24 on: 2016.March.04. 19:53:13 »
Hmmm ... I'm trying to reach the closest match possible to the original functionality,

so yes, when somebody is pushing two buttons on the PS/2 keyboard I'm keeping two lines active on the EP side ...


But I remember some kind of diode on the arduino micro's direct I/O pins ... I try to find the circuit ...
Z80 System

Offline pear

  • EP lover
  • *
  • Posts: 795
  • Country: pl
  • Z80 only
  • OS:
  • Windows 7/Server 2008 R2 Windows 7/Server 2008 R2
  • Browser:
  • Firefox 44.0 Firefox 44.0
    • View Profile
Re: PS/2 keyboard hardware assembly
« Reply #25 on: 2016.March.04. 19:58:14 »
These are probably diodes which protect I/O ports. This is not the same.

Offline Z80System

  • EP addict
  • *
  • Posts: 3939
  • Country: hu
  • OS:
  • Windows NT 10.0 Windows NT 10.0
  • Browser:
  • Chrome 49.0.2623.75 Chrome 49.0.2623.75
    • View Profile
Re: PS/2 keyboard hardware assembly
« Reply #26 on: 2016.March.04. 20:00:59 »
Do these schematics explain something to you about the problem ? :

http://www.atmel.com/Images/Atmel-7766-8-bit-AVR-ATmega16U4-32U4_Datasheet.pdf
Z80 System

Offline pear

  • EP lover
  • *
  • Posts: 795
  • Country: pl
  • Z80 only
  • OS:
  • Windows 7/Server 2008 R2 Windows 7/Server 2008 R2
  • Browser:
  • Firefox 44.0 Firefox 44.0
    • View Profile
Re: PS/2 keyboard hardware assembly
« Reply #27 on: 2016.March.04. 20:03:03 »
Yes, it certainly diodes protected against overvoltage.

Offline Z80System

  • EP addict
  • *
  • Posts: 3939
  • Country: hu
  • OS:
  • Windows NT 10.0 Windows NT 10.0
  • Browser:
  • Chrome 49.0.2623.75 Chrome 49.0.2623.75
    • View Profile
Re: PS/2 keyboard hardware assembly
« Reply #28 on: 2016.March.04. 20:12:46 »
Okay, so as far as I understood now,

you say I could use diodes between the arduino's output pins and the EP motherboard against the "keyboard breaks control ports sometimes" problem.


But If I do that, I cannot read into the arduino on those pins anymore, can I ?

So I planned to switch those pins sometimes from output to input by software, and reading the pushed keys from the membrane keyboard ... for configuration, keyboard mappings and such ...

So if I understood well ... I have to choose between the "keyboard fixing" and the input mode of those arduino pins ... haven't I ?
« Last Edit: 2016.March.04. 20:15:54 by Z80System »
Z80 System

Offline pear

  • EP lover
  • *
  • Posts: 795
  • Country: pl
  • Z80 only
  • OS:
  • Windows 7/Server 2008 R2 Windows 7/Server 2008 R2
  • Browser:
  • Firefox 44.0 Firefox 44.0
    • View Profile
Re: PS/2 keyboard hardware assembly
« Reply #29 on: 2016.March.04. 20:19:27 »
Diodes are needed only on the side of the LS145 decoder. The states on its output, you can only read.
If you want to force a different state than the established by the decoder, the diodes will help you more than disturb.