The LCDuino-1 I/O processor
Sep 28, 2009 at 6:21 PM Post #31 of 403

manaox2

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I can already tell this is going to be wicked. When I get a hold of a few of these, its going to be one of those things I never want stop tinkering with. I can't wait to play with one, must get all this other stuff done so that I can start playing.
smily_headphones1.gif
 
Sep 28, 2009 at 6:28 PM Post #32 of 403

linuxworks

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Quote:

Originally Posted by Beefy /img/forum/go_quote.gif
For something like the Buffalo 32, it reportedly manages the digital volume control extremely well.


glt (posted here) has done some work in talking from his arduino to one of the TP dacs.

I bet he could adapt his code to work with the lcd driver that we have. probably take an hour or two of work, if even that. then, that could be another software plugin to the system.

is head-fi really ready to take on software projects? lol
wink.gif


but you know, it *is* rewarding to add new features and not even have to warm up the soldering iron to do it. and if you make a mistake in software, the parts don't give up their magic blue smoke like they sometimes do in hardware
wink.gif
 
Sep 28, 2009 at 6:30 PM Post #33 of 403

linuxworks

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Quote:

Originally Posted by jnewman /img/forum/go_quote.gif
now I just have to decide if I'm dumb enough to try to cobble together my own rather than using you guys' fine design.
smily_headphones1.gif



you could start with a 'worked out board and software', pick it apart, play with it, learn how it works and then create your own.

I often find that starting with a known working system is a huge help in getting past the learning curve.
 
Sep 28, 2009 at 6:54 PM Post #35 of 403

Beefy

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I have found the LCD displays easily enough at Mouser, but can't immediately find any nice bezel options. Any suggestions at this early stage?
 
Sep 28, 2009 at 6:55 PM Post #36 of 403

dbfreak

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I see my next project coming to light.
smile.gif
 
Sep 28, 2009 at 7:45 PM Post #37 of 403

linuxworks

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the lcd part that I like, these days, is this black background/amber foreground unit:

NHD-0216K1Z-NSA-FBW-L

(at mouser)

I have not found good bezels yet. would love to find some dressing to put in front of the rough-cut rectangular hole, though! just a clear plastic front window and some frame around it; that would be all I'd need to clean up the mounting.

perhaps even just a laser cut rectangle clear acrylic with 4 screw holes. that whole thing could be bolted to the front and make a sort of frame.
 
Sep 28, 2009 at 8:03 PM Post #38 of 403

Beefy

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I'm wondering whether you could just mount it at the back of a rectangular hole on a FPE panel.......?

Though I suspect that the panel would need to be quite thin (or cutout at the back) such that the display comes far enough forward and isn't shadowed.
 
Sep 28, 2009 at 8:32 PM Post #39 of 403

mojo

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Me again.

I am working on a project to create a universal joystick controller for video games. What does this have to do with this project, I hear you ask. Well, I have been thinking a lot about options for expansion.

For example, you are going to target a 16x2 character LCD with direct support. That's cool, but what if someone wants to use a graphic LCD, or just some LEDs to indicate the selected source?

What if someone wants to connect an MP3 player that can do ID3 tag reading, or add any number of other modules...

Being open source they could I guess just add support themselves, but you have a limited number of I/O pins and connecting it all up could get tricky for the end user.

What I decided to do is use a bus system. I have RS232 comms between modules, with the main controller as the bus master. It all works fine as long as modules don't try to talk at the same time, which is not a problem since there is only one bus master and modules only speak when spoken to.

The advantage of this is that you get nearly unlimited expandability and anyone can create their own modules using whatever technology they want. It also keeps everything highly modular. People could even re-implement the main controller themselves and be compatible with existing modules.

It's ambitious but very doable.
 
Sep 28, 2009 at 9:30 PM Post #40 of 403

TeraHz

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Nice project linuxworks and amb. This should be fun
smily_headphones1.gif


I think it is much nicer to have the FTDI chip on the board and add a standard USB i/o, unless you want to preprogram the atmegas. I know the FTDI chip is on the expensive side but it might be worth it to not have to have an extra cable around if you want to program your amp (that sounds nice
biggrin.gif
).
 
Sep 28, 2009 at 9:46 PM Post #41 of 403

DoYouRight

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sweet LinuxWorks you finally got this out there in the public! I was waiting to see more info than what you had told me! This is very exciting!
 
Sep 28, 2009 at 9:47 PM Post #42 of 403

glt

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Quote:

Originally Posted by linuxworks /img/forum/go_quote.gif
one of the design goals was to integrate, on 1 board, some common functions and pre-wire it to make it easy to get that functionality working.

...

so, its mostly a convenience in integration and also establishes a base config that some common software can be run on.

...



I see. Somehow I had the impression that this was intended to be used with another (main) Arduino board. So if this is intended to be used standalone, why not include the usb device? to facilitate programming? That thing alone costs 10-20 bucks as a separate board.

Also, I like 4x20 LCDs because I can't see the little numbers at a distance and with a 4 line LCD I can display numbers that are much larger (9X larger)
 
Sep 28, 2009 at 10:18 PM Post #43 of 403

linuxworks

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Quote:

Originally Posted by glt /img/forum/go_quote.gif
I see. Somehow I had the impression that this was intended to be used with another (main) Arduino board.


it depends on how complex the problem is that you are trying to solve. for some things, this single board can hold all the digital control stuff and the other functionality-boards (volume control or input selection, etc) perform their primary function and simply have some management interface (i2c bus, for example) for a cpu to control it over.

in other cases, it might make sense to have a 2nd local processor receive the i2c serial stream and convert commands meant for it into local bit-banging of some other chip or subsystem. I don't see this as the usual case, though, but its possible to do this and still stay inside the overall architecture.

Quote:

So if this is intended to be used standalone, why not include the usb device? to facilitate programming? That thing alone costs 10-20 bucks as a separate board.


yes, its a $20 cable if you buy it in easy to use cable form. our interface follows the FTDI 6 pin 'standard' (reset on one end; 2 grounds on the other, vcc and tx/rx in the middle) and so this is one way to break down the 2 functions: 'programming' and 'using'
wink.gif


'using' happens much much more often than programming. I think it makes sense to optimize for the typical use case. I could forsee many installers that may be ok with 'off the shelf' applications pre-programmed in the chip and they simply install it and use it. in that case, they never need any host or computer/pc interface. why make them pay for things they don't need or want?

for those that want to edit or change their apps, they can buy the 'download cable' and you buy that once, no matter how many devices you build that use arduino. once you 'flash' them with software that gets sent over that fancy cable, the code stays inside and if you're happy with the code, there's no reason to ever connect that port to a pc again.

some people may want to have a 'ready to use' usb port on the back of their amps and systems. in that case, you can buy a small board that does what the magic cable does:

Arduino miniUSB: USB to TTL converter (FTDI) [v3] - $20.00 : Adafruit Industries, Unique & fun DIY electronics and kits

Arduino "miniUSB": USB to TTL converter (FTDI)

usbmini_MED.jpg


or one like it.

mount that in the rear panel of the amp or dac (note, this is NOT a usb/spdif port, its a 'management port' and talks TO the box, not THRU the box; if you get what I'm saying).

that becomes your management port for when you need to update the box's firmware.

that little usb board just needs those 6 wires sent up front to the lcd area and you're done.

Quote:

Also, I like 4x20 LCDs because I can't see the little numbers at a distance and with a 4 line LCD I can display numbers that are much larger (9X larger)


4x20 uses the same pinout as the 2x16 ones do. the only tricky part is that the mounting holes from the lcd to the daughter board (the LCDuino) won't line up. but its not the end of the world (that's not due for at least a few more years, lol) - the larger 4x20 lcd can mount onto the front panel on its own 4 screw holes and the backpack can 'hang' onto the lcd via the top 2 6pin header strips. there's actually a good amount of hold power in all those pins and header sockets. that may be enough for many people. the lcd mounting to the front bezel is the hard part; but the backpack module isn't in need of the same level of fastening.

its also possible that another board, the same size as the 4x20, could be made using the same general idea as the LCDuino-1. maybe its the -2 version
wink.gif
think of all the extra proto hole room in THAT one
wink.gif


the nice thing about the 2x16 size is that its a good balance of 'real estate' on the lcd and small physical size. it can fit in a 1U rackmount and given that used pro audio boxes can sometimes be found cheaply, its nice to be able to come in under the 1U height.

I've also used double sided foam tape to secure the 'dangling end' of a smaller backpack to the back of a larger display. the top pins holding it and the foam tape were enough for me. ymmv, of course.
 
Sep 28, 2009 at 11:34 PM Post #44 of 403

mojo

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Quote:

Originally Posted by linuxworks /img/forum/go_quote.gif
some people may want to have a 'ready to use' usb port on the back of their amps and systems. in that case, you can buy a small board that does what the magic cable does:


Quote:

4x20 uses the same pinout as the 2x16 ones do. the only tricky part is that the mounting holes from the lcd to the daughter board (the LCDuino) won't line up.


Perhaps there is a solution to both these problems. Instead of using the LCDuino, just use a normal Arduino. Then supply a daughterboard for the LCD. You could use an ATmega8 which costs less than £1, and it would give you both an easy to use and intelligent LCD interface which could be adapted to any size or type of LCD with optional extra LEDs etc, and a USB interface using V-USB. The USB side could use the CDC mode to appear as a serial port on the PC, for remote control and firmware updates.

The mega8 could also act as an I/O expander. You could even incorporate the IR and a button interface into it. You get all that from just two IO pins and can use any Arduino variant.

BTW, I can recommend SeeedStudio for PCBs. They do a fantastic job of them and they are really cheap.
 
Sep 29, 2009 at 12:46 AM Post #45 of 403

linuxworks

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Quote:

Originally Posted by TeraHz /img/forum/go_quote.gif

I think it is much nicer to have the FTDI chip on the board



that chip, while not expensive, has a TINY lead pitch ;( I have an unsoldered brand new chip and board here (a lady ada board) and I have not had the courage to attempt soldering this by hand, yet.

if there are pure software methods that are completely plug compatible with the standard development software, that would be great. so far, though, I have only been using the ftdi-enriched usb cable (lol) and it has worked just great as a download, debug and also as a simple power cable!

builders can decide what route they want to go. if they want a usb port on the back, at all times, they can install a board that has the ftdi (or similar) chip on it. if they simply want to program the chip at home, once, then not have to wire up usb inside their amp, the default install does not force any usb ports or chips on the target box. you just need to get 5v to the board and one easy way is the 'bottom' 3 pins of the 6pin software cable header (2 bottom pins are ground and the pin above it is 5v).
 

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