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geekhack Projects => Making Stuff Together! => Topic started by: What on Thu, 06 August 2015, 07:24:22

Title: Custom Controller for Membrane Board?
Post by: What on Thu, 06 August 2015, 07:24:22

Mod Edit: Split from Simple Questions, Simple Answers thread

Original question:

Quote

Can I take regular membrane keyboard and hook it up to micro controller so I can get all the benefits like multiple layers and reprogrammable keys ?

Quote from: SpAmRaY on Thu, 06 August 2015, 06:59:15

Have a look here

 https://geekhack.org/index.php?topic=72052.0

The USB to USB might help you do some of the the things you want.

I want to try to make it myself, so I can take 2 donors keyboards and make it into one with half keys from one and half from another keyboard) Is it possible?

Title: Re: Re: Simple Questions, Simple Answers (FAQ in the OP)
Post by: CPTBadAss on Thu, 06 August 2015, 07:25:36

Quote from: What on Thu, 06 August 2015, 07:24:22

I want to try to make it myself, so I can take 2 donors keyboards and make it into one with half keys from one and half from another keyboard) Is it possible?

I'm confused as to what you're proposing. Hasu lists the parts he uses for his converter in that thread. You're asking about taking two keyboards and putting them together to make one?

Title: Re: Re: Simple Questions, Simple Answers (FAQ in the OP)
Post by: SpAmRaY on Thu, 06 August 2015, 07:27:44

Quote from: What on Thu, 06 August 2015, 07:24:22

Quote from: SpAmRaY on Thu, 06 August 2015, 06:59:15

Have a look here

 https://geekhack.org/index.php?topic=72052.0

The USB to USB might help you do some of the the things you want.

I want to try to make it myself, so I can take 2 donors keyboards and make it into one with half keys from one and half from another keyboard) Is it possible?

You might post a thread about this in making things together.

I thought you just wanted programmability to an existing keyboard.

Title: Re: Re: Simple Questions, Simple Answers (FAQ in the OP)
Post by: What on Thu, 06 August 2015, 07:59:08

Quote from: CPTBadAss on Thu, 06 August 2015, 07:25:36

I'm confused as to what you're proposing. Hasu lists the parts he uses for his converter in that thread. You're asking about taking two keyboards and putting them together to make one?

please don't laugh))
I like "matrix-type"  keyboards. But the cheapest one is typematrix 2030 (100$) + shipping in Ukraine it'll cost me 150$. So I decided to make some experiment with regular keyboard. I found this keyboard
(http://elmir.ua/img/271749/1200/700/klaviatura_sven_standart_303_white_usb.jpg)
and as you can see it has very nice "matrix-type" layout for first two rows (f* and number row), so I asking here is it possible using dremmel and some micro controller to take two of those keyboards and make one "Frankenstein-keyboard" which will have 4 rows(2 from each keyboard) and will have all benefits of custom firmware)
(http://i.piccy.info/i9/bc8a66acf590b84df84363e3a6e4da61/1438865810/53625/932161/frankinstain.jpg)

Title: Re: Re: Simple Questions, Simple Answers (FAQ in the OP)
Post by: CPTBadAss on Thu, 06 August 2015, 08:01:47

Quote from: What on Thu, 06 August 2015, 07:59:08

Quote from: CPTBadAss on Thu, 06 August 2015, 07:25:36

I'm confused as to what you're proposing. Hasu lists the parts he uses for his converter in that thread. You're asking about taking two keyboards and putting them together to make one?

please don't laugh))
I like "matrix-type"  keyboards. But the cheapest one is typematrix 2030 (100$) + shipping in Ukraine it'll cost me 150$. So I decided to make some experiment with regular keyboard. I found this keyboard

Show Image

(http://elmir.ua/img/271749/1200/700/klaviatura_sven_standart_303_white_usb.jpg)

and as you can see it has very nice "matrix-type" layout for first two rows (f* and number row), so I asking here is it possible using dremmel and some micro controller to take two of those keyboards and make one "Frankenstein-keyboard" which will have 4 rows(2 from each keyboard) and will have all benefits of custom firmware)

Show Image

(http://i.piccy.info/i9/bc8a66acf590b84df84363e3a6e4da61/1438865810/53625/932161/frankinstain.jpg)

Definitely beyond the scope of this thread. But no I don't think it'll work with rubber domes without a ton of modifications to the membrane. Have you tried making your own with MX switches? Here's an example from fknraiden (https://geekhack.org/index.php?topic=74223.0). Or have you looked into the Planck? Or have you looked into getting a Point of Sale board which has a matrix layout? Such as this Tipro? (https://geekhack.org/index.php?topic=72100.0)

Title: Re: Re: Simple Questions, Simple Answers (FAQ in the OP)
Post by: What on Thu, 06 August 2015, 08:17:29

Quote from: CPTBadAss on Thu, 06 August 2015, 08:01:47

Definitely beyond the scope of this thread. But no I don't think it'll work with rubber domes without a ton of modifications to the membrane. Have you tried making your own with MX switches? Here's an example from fknraiden (https://geekhack.org/index.php?topic=74223.0). [/url]

No I did not, currently I have Kinesis Advantage at home and just want to do this little experiment )

Quote from: CPTBadAss

Or have you looked into the Planck?

Plank cost even more than typematrix

Quote from: CPTBadAss

Or have you looked into getting a Point of Sale board which has a matrix layout? Such as this Tipro
 (https://geekhack.org/index.php?topic=72100.0)

Actually I found out about those yesterday, so I will look more into it. 

Thanks anyway, I will still try it) Will make a thread if I will succeed.

Title: Re: Custom Controller for Membrane Board?
Post by: njbair on Thu, 06 August 2015, 11:14:40

Discrete switches (Cherry MX, Alps) are more well-suited for layout changes than membranes. In fact, I'm going to go ahead and call what you're asking for impossible.

That said, if you're willing to go through the work to hack & splice those two membrane keyboards, it's probably actually less work to make a plate (or have one made) for Cherry switches. You can hand-wire them if you want to avoid spending money on a PCB.

Title: Re: Custom Controller for Membrane Board?
Post by: Findecanor on Thu, 06 August 2015, 16:17:09

You would be limited by how the traces are on the membrane. They may have to spill out a whole lot to the top, bottom and sides only because there are important traces along the edge that you can't cut off.
You will have to use the contacts to the membranes, and those are probably near where the LEDs are. You would also have to use both contacts,.
Not all membrane keyboards allow the keycaps to be rotated 180°. No scissor switch keyboard does.

Membrane keyboards don't have diodes in the keys for N-key rollover, so they instead use larger matrices with more pins. How many depends on the particular matrix on the membranes.

I think that the real breaking point however, could be that the keys that you intend to use as modifiers might not be pressed together with every key that you intend to use as an alphanumeric key.
On a keyboard without diodes, the matrix has to be specially designed to allow the modifiers to be pressed in certain key combinations. Microsoft and other OS vendors have published lists of key combinations that keyboard for their system must support, just for this purpose.

I would instead recommend that you look for a good deal on a point-of-sale/cash register keyboard. These are often in matrix layout, or with staggered QWERTY + a few rows and/or columns in matrix layout.
There are brands such as Tipro and Access-IS that use mechanical switches with diodes for N-key rollover. These keyboards are often also programmable with special software ... but might require a real PS/2 port , not through adapter, not even Soarer's or a Blue cube.

Title: Re: Custom Controller for Membrane Board?
Post by: What on Thu, 06 August 2015, 17:25:56

Really good points guys! Thanks a lot!

I spent whole day looking into different models of pos keyboards, and as was mentioned a lot of them have matrix layout and mechanical switches. I even found couple local brands! Like this one

http://www.posua.com/en/products/standard-pos-keyboards/lpos-ii-128#gallery
 
Now will try to find one on sale) thanks again!