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Topic: Board & shields design: lousy. This is just a shame. (Read 2473 times) previous topic - next topic

Stan09

Jun 23, 2012, 02:53 am Last Edit: Jun 23, 2012, 03:10 am by Stan09 Reason: 1

Ard Duemilanove with shield.
Whoever came up with 'shields' idea - don't you guys realize this is very lousy design?
Change USB connector to  USB-mini and power connector to anything less bulky.
FEZ Panda has mini-USB, but still the same ugly battery connector  which does not allow  to connect any shield in a normal way.
With design approach like that you will always stay on  amateur's level


drjiohnsmith

I must agree.

its impressive what the Arduino has achieved,
   BUT.

the edges are getting ragged are they not.
   
I note the long pin connectors used in the shields are of a low quality,
   OK, cheep, but they are not reliable over time,


DuaneB

Hi,
   I think Arduino is fantastic for getting up and running quickly, however I have to agree that a lot of shields are a bit of a dead end.

   A major positive which more than compensates for the layout quirks is that the transition to standalone builds with whatever layout and connectivity you require is super easy and very well supported.

EDIT: Just noticed that this is in suggestions - so yes, better layouts on the entry level boards would be great.

   Duane B.

rcarduino.blogspot.com

Read this
http://rcarduino.blogspot.com/2012/04/servo-problems-with-arduino-part-1.html
then watch this
http://rcarduino.blogspot.com/2012/04/servo-problems-part-2-demonstration.html

Rcarduino.blogspot.com

Graynomad

Honestly the use of that huge USB connector after it was realised that there's a problem just defies belief. In the past people have argued that it's required for backwards compatibility...what? Buy a $3 cable.

______
Rob
Rob Gray aka the GRAYnomad www.robgray.com

cwrose

The Arduino Ethernet doesn't in fact have a USB connector - it just uses
the FTDI pins.  The real irritation is the non-standard shield pin separation,
but now cranked pins are available you can build on 0.1 matrix boards
without problems.  Generally it all seems to work.

Will

Stan09


The Arduino Ethernet doesn't in fact have a USB connector - it just uses
the FTDI pins.  The real irritation is the non-standard shield pin separation,
but now cranked pins are available you can build on 0.1 matrix boards
without problems.  Generally it all seems to work.

Will


Will, many "arduinish" boards don't have USB and bulky power connector. My point is that the main, basic and most popular boards were designed even without minimal consideration on how the shield should be attached. It takes a minimal effort to fix it - install mini-USB and shift power connector forward 0.1" and the problem is solved - but it takes time, motivation and some effort. All this was missing. Hence, 'lousy'.

Graynomad

Quote
basic and most popular boards were designed even without minimal consideration on how the shield should be attached. It takes a minimal effort to fix i

+1

I think there was more time spent designing the stupid shape so the boards would be "different" and not have standard mounting points.

All this sort of thing should have been fixed after the first prototype.

______
Rob
Rob Gray aka the GRAYnomad www.robgray.com

westfw

To be fair, you should consider that the original design pre-dates the discovery of "stackable" headers.  (inexpensive stackable headers were a duemilanove-timeframe thing.  Pretty late in the overall scheme of things.) The spacers on a standard male header strip add about 0.1 inch of space, which is just about enough that this "lousy" problem isn't a problem (or at least not as much of a problem.  You still didn't want to put TH leads directly over the USB connector.) As shown by this "Wave Shield" on a MEGA (the WS pretty much has to be on top anyway, so it didn't get stackable headers.)

If you use "correct" stackable headers, there is still room to add such spacers (um, protoshield on a Freeduino prototype, I think.  The connectors are a bit funky on this one (wrong part # ordered), but the principle is the same):

Or you can just go a little bit overboard and use very long stackable headers, completely avoiding the issue (this is an older ethernet shield on a Solarbotics clone, which uses a mini-usb anyway, but you get the idea!):


Hi westfw,
just curious as to where you source your stackable headers? I've seen the parts sparkfun offers (http://www.sparkfun.com/products/10007) but these are too short (i have a componet that is 15.2 mm high) and don't contain the 18x2 and ICSP 6x2 headers for the arduino mega ADK. Samtec offers these with long pins but the 18x2 header is quite expensive when bought from the company directly (no one else seems to sell them)

Thanks

CrossRoads

These kinds of parts?

http://www.pololu.com/catalog/product/1114
http://www.pololu.com/catalog/product/1113
http://www.pololu.com/catalog/product/1115
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

westfw

Quote
where you source your stackable headers?

Well, I'm not "manufacturing", so I've been surviving with Samtec samples and whatever vendors ship me in their kits.  Adafruit says they get their connectors (also with 10.5mm leads) from 4ucon, and 4ucon also has a 15.5mm lead version, at least in 6/8 socket varieties.  Minimum order quantity: 20,000.  Ouch.

The ChipKit folk also discovered that "stacking" headers are depressingly expensive.  I generally try to avoid stacking shields too much, and most of the homebrew things I make I build without stacking capability.  By the time you start having stacks more than three high, it's time to start thinking about designing your own shield, or using a non-shield style of construction.

drjiohnsmith

I agree about the stack of three 'limit'

found out by bitter experiance, reliability drops off quickly,

I'd love a shield with IDC connectors to ribbon cables, so that signals can be moved off to custom boards easily,



   

Jantje

I have a stack of 5 running with no problems.
You have to take the power usage into account offfcourse. I'm drawing more than 1 amp now. I can't feed the Arduino with 12 volt but 9 is OK.
Best regards
Jantje
Do not PM me a question unless you are prepared to pay for consultancy.
Nederlandse sectie - http://arduino.cc/forum/index.php/board,77.0.html -

Stan09

This is all nice and dandy. What it has to do with "Suggestions for Arduino Project"?
My suggestions:
1. Install on future Ard board mini-USB jack instead of current one
2. Change PCB design so that battery jack should be shifted forward ~ 0.1"
This will allow shield stacking in a nice and professional way.
Objections?

westfw

mini-usb is pretty much obsolete.  You might as well go to microUSB, which is smaller, spec'ed for more insertions, and is a standard for power supplies in some countries.

And you might as well get rid of the power jack entirely.  It's a throwback; nowdays it's easier to to find a regulated 5V power supply with USB output than it is to find the "ideal" ~9V supply.  More people have trouble with and questions about the onboard regulator than would have problems with always powering via USB.  IMO.  And the power switching circuit keeps expanding in cost and complexity.  And the regulator is really good for much more power than you can get from a USB port anyway...

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