LED discussion

[7bit]

I know there was a thread on that other website, but I didn't find one here.

Is it possible to use a matrix for the diodes, or does every diode need its dedicated connection to the controller?

I found this somewhere and wonder if it works with a teensy or teensy++ controller:

[Soarer]

See the light.

[7bit]

See the light.

I know, but I don't want to read through all those pages.

[Soarer]

Then start at the end, numb-nuts!

If you only want on/off or single overall brightness control, then maybe. It still requires external components to provide enough current.

If you want individual brightness, or just an easy life, then go for the chip that __red__ found.

If you want a more in-depth answer... RTFT!!

[7bit]

Thanks!

But at the moment I only need to know how the LEDs should be 'wired up'. Alternatively, I just can leave holes and you LED-fetishists can wire them with real wires instead of just soldering them into a pre-existing keyboard matrix.

[Soarer]

Might be best. There's no telling what levels of wrongness will be reached if you rely on some lazy-assed old bugger like me to give you an answer!

Besides, you haven't even said what you'd like to achieve with said LEDs... simple glow, or fancypants stuff?

[7bit]

I think it should be doable with that matrix if it is just on/off all in one color a time. I don't think there is enough space on the PCB for anything more fancy. One option would be to have a separate LED-PCB.

I just want to save time and concentrate on one thing and don't want to get into more detail than necessary to know how to place the traces for the LEDs.

[Soarer]

Well yeah, I was assuming just one colour, since multicolour would be 3x the pain.

If you don't want to be able to draw patterns with them, then you don't even need a matrix.

You will at least need to go into enough detail to understand some of the tradeoffs in different methods... and most of them were discussed in that thread.

edit: for the simplest option, dig out the Deck schematics.

[tlt]

Maybe doing it with Charlieplexing like the LOL shield http://jimmieprodgers.com/2009/12/my-de ... t-process/.

[tlt]

Sorry, Im tired I guess that matrix is the same thing.

[7bit]

Sorry, Im tired I guess that matrix is the same thing.

Yes, seems so. Thank you for that link. I think it will be the way I'll do it. If someone needs it more fancy it is still possible to wire them up manually.

Next step for me: writing a script to generate the scheme file.

[Soarer]

It was painful enough watching you start to design PCBs, but this is really making me want to scream STOP! now

Sorry to be so blunt.

If it was just you doing it for yourself I'd be all for it.

But for a group buy? No. Really. This is getting ridiculous.

[tlt]

I think its great that 7bit is doing this, it's the kind of thing I like about this community.

[7bit]

It was painful enough watching you start to design PCBs, but this is really making me want to scream STOP! now

Sorry to be so blunt.

If it was just you doing it for yourself I'd be all for it.

But for a group buy? No. Really. This is getting ridiculous.

Don't see the point. I conquered the keyboard itself, now I can add some fluff to sell more.

[Soarer]

I think its great that 7bit is doing this, it's the kind of thing I like about this community.

I hear the Top Gear presenters are starting a group buy on convertible MPVs... want one?



At least they tried a prototype!

[tlt]

Yeah! why don't they have those at my local car dealer?