The LCDuino-1 I/O processor - by amb and linuxworks

[n_maher]

Oh effing snap.

The LCDuino-1 I/O processor - Head-Fi: Covering Headphones, Earphones and Portable Audio

Introduction

Ever since I built my β24 power amplfier, I've been wanting to build a high-end pre-amp to match. However, rather than using ordinary rotary switches for input/output selection, and a conventional potentiometer or stepped attenuator based on a mechanical switch for volume, I wanted to do something better.

There are off-the-shelf solutions available for relay-based selectors, relay-based, chip-based or motorized pot volume controls, etc., but virtually all of them are designed for a singular purpose, some are operable with a remote control, some not. Some have a display for status, some don't. It would be nice to have all of those features, yet implement it in an extensible manner such that more capabilities could be added without wholesale redesign, and to allow a builder to tailor the system to suit his/her exact needs.

Many of you may have noticed the recent Arduino-based LCD driver circuits that linuxworks built on perfboards, controlling a myriad of devices such as the input/output selector and volume control for his β22, a S/PDIF input selector, and even an Espresso machine monitor/controller. Many months ago we began exploring the idea about turning the basic concept into a generic, extensible and modular platform, usable for many applications not only for audio, but other devices too.

Arduino is attractive because of the rich set of tools, libraries, code and support available for firmware development. It uses the C programming language and the GNU C compiler (gcc) in a nice graphical integrated development environment. The environment runs on Linux, Windows and MacOS X. There is also a large and active Arduino programmer and user community where Open Source is de rigeur. In all it's a very exciting and dynamic scene and fits perfectly with the spirit of our project and goals.

The LCDuino-1

The first result of this collaboration is the LCDuino-1 I/O processor, which will serve as the "heart" of the entire framework.

LCDuino-1 is basically an LCD driver circuit based on a customized Arduino platform with some extra features. This board has two 6P pin headers which will mate up with matching receptacles on an industry-standard 2 row x 16 characters LCD module. These LCD modules are available in various colors and backlighting, both transmissive or reflexive. The LCDuino-1 has the same form-factor as the LCD module, with matching screw hole locations. When mated together, they become a two-board "sandwich" that is easily mounted to an enclosure's front panel. An example of the LCD modules is the Newhaven NHD-0216K1Z-NSO-FBW-L amber transmissive display. LCDuino-1's slim profile allows the assembly to fit in a 1U rack case. Off-the-shelf front bezels are available for these LCD modules.

Depending on the nature of the application, the LCD display would show the current input/output selection, a volume control bargraph, the date and time (see below), or some other information as appropriate.

It is worth noting that the LCD module is actually optional, LCDuino-1 could function without one. There may be applications where no display is required, yet LCDuino-1 could still serve as the control center.

The main component on LCDuino-1 is the Atmel ATMEGA328P microcontroller. See the datasheet for chip features, you'll notice that amongst other features, this microcontroller offers many digital and analog I/O ports, [url=http://en.wikipedia.org/wiki/I%C2%B2C]I

Edited October 1, 2009 by n_maher

[digger945]

Oh effing snap.

yea really. I have not read it all completely yet but it looks sweet thus far just skimming it over.

[Beefy]

I became aware that this was happening a couple of days ago - good to see the official anouncement.

Hugely ambitious project, but with lots of people behind it adding their bit, and AMB at the core of it..... I can't wait!

[Pars]

Very cool. Looks like a nice alternative to dantimax.

[Nebby]

Very much looking forward to this

[manaox2]

Nice! I'm really impressed that AMB and co. are spear-heading this.

Twisted pear audio I think also have a similarly planned audio controller device, but they have too much on their hands as usual. This seems to be more flexible possibly as well, I can't wait to see what crazy uses people find for this.

[Beefy]

This seems to be more flexible possibly as well, I can't wait to see what crazy uses people find for this.

The possibilities are indeed mind blowing.

Personally, I just want to see a compact/integrated volume control and input selection. Most on the market take up huge amounts of case space, are quite expensive, and have larger-than-reasonable power supply requirements.

I'm especially wondering about the PGA volume control...... anyone know if this is the same module that Justin is using in the new Pico Slim? Or is that something even better again?

[Grahame]

Sweet.

Now I know what Ti meant by his cryptic "Watch this space" announcement at the recent nor-cal meet.

Now people will need to rethink their HiFi2000 front panels

[Beefy]

Now people will need to rethink their HiFi2000 front panels

Already on it

[morphsci]

^^Ditto^^

[swt61]

While I have to admit to not understanding all of the operational computer jargon, I think this is awesome! It sounds similar to TPA's controller, but even so much more customizable. The applications are vast, and oh so cool.

[n_maher]

It sounds similar to TPA's controller <snip>

It is except:

1. It'll be available.

2. It'll be in stock.

3. It won't be "upgraded" 2 days after you place your order.

I love the Twisted Pear guys but holy heck, they are their own worst enemy some days.

[swt61]

It is except:

1. It'll be available.

2. It'll be in stock.

3. It won't be "upgraded" 2 days after you place your order.

I love the Twisted Pear guys but holy heck, they are their own worst enemy some days.

Oh I couldn't agree more! The fact that Ti is behind this is the best part!

[n_maher]

Oh I couldn't agree more! The fact that Ti is behind this is the best part!

If rumors are to be believed I'm on the prototyping team so HC should get a nice inside line on development.

[Hopstretch]

If rumors are to be believed I'm on the prototyping team so HC should get a nice inside line on development.

So people won't just be asking you to build shit from now on, but also to program it. You must be thrilled!

[swt61]

Sweet!

I kind of assumed Naaman might be on there too? It'll be interesting to see the implementation.

[n_maher]

So people won't just be asking you to build shit from now on, but also to program it. You must be thrilled!

I fill the "some idiot might try this" requirement. And I doubt they'll ask me to program anything, although I am pretty good with my TI-85.

[linuxworks]

....and it makes coffee, too:

there's a lot more to this than just audio.

well, probably not at the same time, though (lol).

[n_maher]

welcome linuxworks, when I posted this thread I was not aware of how intimately you were involved in this project. I've appropriately updated the thread title to give credit where it is certainly due. Well done, the both of you.

[Grahame]

Welcome linuxworks.

That's quite an impressive first post!

I think you'll like it here.

[Dusty Chalk]

Welcome linuxworks -- I doubt you'll have to worry too much about your thin skin or ducking shovels, but be aware that they fly about quite a bit, willy nilly even.

Yes, people are virtually flayed (and filleted) here.

So...sorry if you have a weak stomach to observe such things, even if from the sidelines.

[Fitz]

....and it makes coffee, too:

But can it play audio through the coffee?

[linuxworks]

hey guys

took me a while to find this place.

it was under a bunch of socks. I think.

anyway, yeah, amb and I have been working on this quite a while, now.

I hope people like the software, as well. there's a lot it does right now, and there's still *plenty* of code space left in this chip

I've had a web *server* running, web *client*, x10 firecracker (wireless powerline control) and like I said in my first post, some non-audio things, as well.

we're hoping it becomes a platform for things that need integrated and common i/o, such as the lcd and an IR input. that, and sample code will get people up and running very fast, we think. we hope

there just wasn't much out there that did this kind of thing. I went thru a bunch of closed-source hardware and software partial-solutions - mini boards that did this or that - and got tired of having to work it that way. the arduino 'way' is to release source and make it easy and affordable for anyone to get the source, modify things and push it back into the device. *they* now control what this thing does, not the manufacturer. I kind of like it, this way

[Dusty Chalk]

Being a programmer (probably my main forte, for those that think I'm a goofball at everything), I approve. Will definitely be following this closely.

[linuxworks]

But can it play audio through the coffee?

(cough)

scuze me.

I *am* working on some audio for that system. yes. some PID controllers have a piezo buzzer. I wonder if speech synth is possible? or even sensible (lol).

seriously, when you start an espresso shot, its *supposed* to be 24 seconds and you can't watch the clock and also the quality of the shot. it would be nice to *hear* a count down. or something.