Which controller?

[iandoug]

HI

So I'm busy building my first keyboard and need to pick a controller. Should I stick with Teensy2++ or use the 3.1 which is a bit cheaper and newer, though no idea why... Or am I barking up the wrong tree?

thanks, Ian

[Muirium]

How many pins do you need? What's your matrix look like?

[iandoug]

How many pins do you need? What's your matrix look like?

19 columns and 8 rows. But some of the keys need to be a bit smart, like sending "00" ...

I have yet to join the movement to greatly reduced keycounts.
Think there's 121 keys last time I counted.

thanks, Ian

[Findecanor]

I would go with a Teensy++ 2.0. All its digital IO lines are available as holes that you can put pin headers in and use with a socket and/or a stripboard.
While the Teensy 3.1 has more than enough I/O lines, only 24 of them are available as through-holes. The remaining holes are available only as pads and those are more difficult to solder.

The Teensy++ 2.0 has 8-bit AVR microcontroller for which there are several firmwares available, while the Teensy 3.1 has an ARM Cortex M4 for which there is so far only HaaTa's Kiibohd firmware. (that I know of)

[Muirium]

Teensy 2++ is the way to go. Much easier to work with, as Fin says, and lots of software available. The price is annoying but not a ripoff. You're paying for things beside the little processor.

[flabbergast]

The Teensy++ 2.0 has 8-bit AVR microcontroller for which there are several firmwares available, while the Teensy 3.1 has an ARM Cortex M4 for which there is so far only HaaTa's Kiibohd firmware. (that I know of)

Also, kiibohd firmware would require a bit of fiddling with the sources (since by default it's only for the infinity keyboard and the chip is slightly different): http://deskthority.net/workshop-f7/alte ... 35-30.html

[iandoug]

Thanks guys, I'll order the 2++ then.

cheers, Ian

[chzel]

Mu, you got it all wrong, if there is a right tree and a wrong tree, shouldn't the wrong tree be the left tree?
Now you have a right left tree and a wrong right tree when you should have a left wrong tree and a right right tree.
A RIGHT² TREE!

OT: go for 2.0

[Muirium]

Woof.

2.0 hasn't enough pins for a slab of a keyboard like this. Must be 2++.

[chzel]

Yes of course, got confused with the trees!

[iandoug]

Woof.

2.0 hasn't enough pins for a slab of a keyboard like this. Must be 2++.

The slab borrows design ideas from MS Natural original and Maltron. Key area is less than 42 cm wide.

Last question: with or without pins?

Jesse says "I bought a pair of Teensy++ microcontrollers from PJRC. Initially, I opted for the ones with pins. I later regretted that. Still later, I unregretted it. "
http://blog.fsck.com/2012/12/building-a ... art-1.html

I assume the pins are useful for 'test wiring' to see if everything is okay, and then you remove them for assembly?

Or do they stay in, and we connect with connectors? On his video, he says to buy the jumper wires with the connectors.

thanks, Ian

[Muirium]

Pins are for breadboarding and custom PCBs. If you're thinking of anything else, go pinless.

What build guides have caught your eye? What are you planning, construction wise?

[flabbergast]

Pins (both on teensy and on jumper wires): Useful if you want play with a breadboard: https://en.wikipedia.org/wiki/Breadboard

Other than that, if the pins are soldered on the teensy the way they usually are (i.e. perpendicular to the PCB), then they just waste a lot of space under the keyboard.

I suppose most people wire the teensy like this: http://i.imgur.com/dghdlvu.jpg (taken from http://imgur.com/a/jLRFM )

Kinda rarely, people go with pins: http://i.imgur.com/MV7oEX4.jpg (taken from http://imgur.com/a/8MuFA ) This makes it easy if you want to "rewire" i.e. change which row/col is on which pin. As far as I can tell, it does not serve any practical purpose, only if you want to try a firmware which doesn't come with sources and requires a specific wiring. By the way, these pins used here are "right angled", i.e. not the ones that come with a Teensy.

EDIT: Oh, shucks, for the second time in this thread Muirium typed faster...

[Muirium]

Typed faster… on an iPhone! Are you on Browns or something?

[flabbergast]

Typed faster… on an iPhone! Are you on Browns or something?

... Apple laptop keyboard ... (/me quickly runs away and hides)

[iandoug]

Pins are for breadboarding and custom PCBs. If you're thinking of anything else, go pinless.

What build guides have caught your eye? What are you planning, construction wise?

Okay, I was suspecting those pins would be an issue.

I have yet to find The Big Dummy's Guide to Building a Keyboard, Google refuses to tell me where it is.
So I have looked at:
Jesse: http://www.slideshare.net/obrajesse/bui ... om-scratch
Matt: http://deskthority.net/workshop-f7/buil ... t5761.html
Jesse: http://blog.fsck.com/2012/12/building-a ... art-1.html

and the one posted above by Matt (thanks flabbergast) also looks useful: http://imgur.com/a/jLRFM

If anyone knows where the Big Dummy's guide is, please share

Like Jesse, could not find board I liked and there are things about my MS Natural that annoy me. And hurt my thumbs. So I kinda went back to other people's drawing boards and copied what I liked. And threw in a few ideas of my own.

The saga is detailed here: http://iandoug.com under Keyboards. Last design has changed a bit slightly.
I have NO Idea how practical this is going to be, or even if I will be able to get the desired bells and whistles to work.

So as per Jesse's video I want to build from scratch. Current areas of research are case construction (have found laser cutting places here in Cape Town for both acrylics and metals). Have generated a CAD cutout, busy tweaking it. Need to do the case outlines since between the layout editor and the CAD generator, something got broken.

My other big problem is how to mark the keycaps. Have looked at laser or dye sub, but not found anyone to do either, and doing it myself (as in: buying the toys) will be expensive. That was going to be the topic of another thread...
I ordered PBT DSA caps from Signature, stabilisers from WASD, and Cherry Brown from Gon (only place I could find them, just wish he would let me know what's happening).

thanks, Ian

[chzel]

Have a look here as well, great construction techniques.

[iandoug]

Have a look here as well, great construction techniques.

Very neat, thanks