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Author Topic: Exact pin space D7-D8: Mega vs Duemilanove  (Read 1151 times)
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Hi,
in description of Arduino Mega I see that "distance between digital pins 7 and 8 is 160 mil (0.16"), not an even multiple of the 100 mil spacing of the other pins"
There are same words in Duemilanove description.
I check Eagle files for Duemilanove. Yes, pin space D7-D8 is 160 mil.
But, in Eagle files for Mega I see pin space D7-D8 only 150 mil.
Is it bug? What is right pin space D7-D8 for Mega?
Of course, 'right space" IMHO should be x100 mil to be compatible with breadboards, but why Mega layout have 150 mil instead of 160 mil?
Please clarify.

Thanks.
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Over the next 10 years, they will gradually move the spacing back to a 0.1 grid!
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Over the next 10 years, they will gradually move the spacing back to a 0.1 grid!

LOL, we can call it the Italian method!

Lefty

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Watch it! :-)

I don't think it's just the Italians -- after all, over on this side of the pond we're still dealing with NTSC television and QWERTY keyboards, just to name a few ancient immovable standards.
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Ok, "...will be .. move ... to 0.1 grid". Excellent!!!
However, first question - 0.1 grid is 100 mil or 200 mil or ...?  smiley-wink
second - starting from what date WILL BE?  smiley-wink
third - what WILL be with a lot of current "wrong space" shields?

Still main question - what is CURRENT exact (real) space between D7 and D8.

Thanks!
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Still main question - what is CURRENT exact (real) space between D7 and D8.

I forget, but if expressed in inches it uses a lot of digits to the right of the decimal point.  smiley-grin

Lefty
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Let's express in mils. If you switch grid in Eagle from mm or inches to mils, you will see what I am asking about.
D7-D8 space from Eagle files:
- Arduino Duemilanove = 160 mils
- Arduino Mega = 150 mils
- Ladyada.net shields  = 155 mils

Think, if I will make PCB from these files, my boards will be incompatible...  :'(
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In reality you can probably easily 'spring' the pins if they are only 0.01 inches out.  Quarter of a millimetre is neither here nor there. Pity the same can't be said about .05 inches, then the initial 'cock up' wouldn't matter smiley
I have a cheap Arduino clone from Hong Kong, and the shield fit wasn't as 'nice' as a real one.  Once I'd plugged it in and out a couple of times it 'adjusted' itself.
« Last Edit: October 03, 2009, 02:40:54 am by stephen_t » Logged


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And what about original Mega and Duemilanove?
Is it really have 10 mil difference for D7-D8 or it's just "bug for clones" in Eagle files? smiley-wink
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