Why endusers may prefer 'shields'

LoopyByteloose

Simply put, when working with good modularity - the end product looks good. It also looks easy. And people are more willing to show their friends a project that looks good. And of course, their friends are find it much easier to be impressed. Gangster Gadget is doing a lot of the right things with the physical configuration and I suspect I am going to be doing more shopping there in the future.

That all may seem rather dumb, but it may be a significant sales factor with that other product - the one with AVR chips.

I am about to start another SX28 Proto Board project and it is with a certain amount of trepidation that this pristine board is going to look somewhat beat up by the time I finish. You may have noticed that I never show my finished projects as they are rather humble. And I am always dreaming of how I might make the board look better.

And so, more modularity may be a significant factor at the cash register; whilst a survey of how many times you see a finished Proto Board may show they are rather rare.

BTW - Code-wise I still think that "A"-thingy is rather a sham, but they have gotten 'social networking exploits' down pat. SPIN is not hard and there is Propeller Basic, and Forth, and C.

GordonMcComb

New ideas tend to come from old. The very popular PC104 SBC form factor (dates back 25 years) was designed with "stacks" in mind; not only do the stackable boards provide an easier method of building circuits, they tend to be mechanically stronger than methods that use backplanes, and cheaper to make than those requiring cables.

The guys who did the Arduino -- " the one with AVR chips" -- knew all these things when they produced their first reference designs. In fact, I bet they had PC104 and similar time-tuned boards in mind.

About half my Arduino-based projects use shields, and half use point-to-point connections, usually with cables I make myself. Those that use shields always seem to present pin conflicts that require making compromises (or trace cutting), so the idea isn't without its pitfalls. (The problem isn't nearly as common when using the Mega, but that's besides the point.)

-- Gordon

LoopyByteloose

Parallax Proto boards seem to be optimized for wire wrap - and that is very rare to find these days.

I suspect DIP breadboards are on their way out as board pins tend to be a bit too large for them and wear them out quickly.

@GordonMcComb
I know you prefer DIP to SMDs and I do too. Things have gotten a bit too small for comfortable construction, especially when the work is a trial run.

rod1963

The Ardunio isn't targeted at the same market as Prop - which is artsy crafty types who don't want to learn how to write a device driver or IIR filter in assembly.

In regards to the shields, they make electronics easy, again for people who either lack the skills or don't want a large amount of time prototyping. For them it's easy to buy a pre-made board that does what they want.

Lastly, if anything the Arduino points to how critical good software is to gaining a market and creating a mind share. Being open source probably helped a lot as well since it allowed a multitude of others to implement the hardware and add to the software.

GordonMcComb

I don't think the Arduino's perceived ease, or its use of shields, have much to do do with its market. That's why I noted the PC104. That was strictly for engineers and designers to make one-offs and short-run products. It used "shields" (just didn't call them that) well before some of the Arduino guys were out of grade school.

The fact that B is easier to use than A doesn't mean A is for pros, and B is for consumers or other non-tech groups. It simply means B will used by both groups. Pros have looming deadlines, demanding bosses, etc. etc., and will look for the easier solution every chance they get.

-- Gordon

kwinn

Modular and stackable are a great idea, and do make for sturdy good looking finished products. The Gadget Gangster Propeller Platform and the modules that go with it are excellent products that can be used to produce very professional finished projects.

If there are modules to perform the functions required for a project this would definitely be the way to go. Unfortunately there are a lot of projects that require functions that are not available on a module, or would require a large number of modules, most of which would have only a small part of their functionality used.

In such a project it might be preferrable to use a Protoboard, Propeller Platform, or similar uC module as the central component and have a number of simple single function add on modules that plug into the central component for control signals and power. Modules that require high power or voltages would plug into a separate power supply. Having these modules makes for rapid project development and a professional looking product.

My own modules include RS232, RS422, RS485, Weigand, TPIC6595, MCP3208, Quad Comparator, and Quad Optoisolator. Most are small boards with a single chip, bypass capacitors, and thru holes for header pins or wires. When mounted in an enclosure or on a metal sheet with neatly routed cables they make for a good looking finished product.

Phil Pilgrim (PhiPi)

Unless you have a bus that allows addressing, stackable modules are a problem due to the possibility of pin conflicts when you've got more than one person designing the plug-ins. Parallax ran into this issue with their AppMod adapter. For microcontrollers without a dedicated address bus, I think it's much better to provide multiple accessory connectors, each with power, ground, and a handful of port pins, so that boards can be installed side-by-side, rather than stacked. This alleviates the necessity for a "pin-assignment czar." Besides, pass-thru connectors tend to be expensive, and they're a pain to solder, since you have to be careful not to get solder on the pins themselves.

-Phil

PJAllen

Kramer,

You're just stirring the pot.

An enclosure can hide a multitude of sins.

I haven't seen anyone rage on anyone his project for worksmanship. So what if they did though? It's an anonymous forum.
If a guy's doing unsound things or makes unsupportable claims then it's a different matter.
[I'll take a crude hodge-podge, anything concrete, over 70+ pages of lunatic Nihil, vaporware extraordinaire, anytime!]

For all the pluses and minuses of plug-in modules, by whatever name, I see projects that, practically invariably, look less-than-slick, crudely stripped and horribly mangled wires crammed into SIP headers and so on, anyway.

Get on with it! Do something real!

Clive Wakeham

I prefer shields compared to either single boards with only ports allowed for expansion, or plug in boards similar to in PC's.
A form factor of the shields, especially the Gadget Gangster type allow for quick and easy upgrading without changing the main processor board. Also having them able to stack ontop of each other reduces the space they use up.