BTW: If anyone invents a time machine, please go back and get the original Arduino header alignment fixed.
The TRE has all of the arduino signals on a 2x17 0.1" header, the one with a white background around it (which seems to mean 5v-safe / AVR-connected on the TRE). Then there's also the remaining double-row headers, which I'd assume are arranged on a 0.1" spacing in relation to each other, and are possibly a new Arduino standard for a 3.3V-only header layout.
It's still not perfect, though. Personally I wish they had made the new standard headers closer together than the old headers instead of further apart, to make it possible to at least bridge across some of them with a $10 5x5cm PCB (even the existing Arduino header standard is just a bit too large to fit on a 5x5cm board, and that's the standard lowest-price tier at all of the super cheap chinese PCB services). But I guess if you only need access to the Uno-era Arduino pins, you can now fit everything into a ~4.4cm long double header. But it's a double header, so you can't make your 'shield' able to pull double duty by plugging directly into a breadboard, which you could have if there had been two close rows of 5V headers instead of a single double-row.
But it is an improvement, and the form factor does have a history of working, a single double-row header is the basis for the entire Pi-Crust/Plate/Shield ecosystem.
Comments
The TRE has all of the arduino signals on a 2x17 0.1" header, the one with a white background around it (which seems to mean 5v-safe / AVR-connected on the TRE). Then there's also the remaining double-row headers, which I'd assume are arranged on a 0.1" spacing in relation to each other, and are possibly a new Arduino standard for a 3.3V-only header layout.
It's still not perfect, though. Personally I wish they had made the new standard headers closer together than the old headers instead of further apart, to make it possible to at least bridge across some of them with a $10 5x5cm PCB (even the existing Arduino header standard is just a bit too large to fit on a 5x5cm board, and that's the standard lowest-price tier at all of the super cheap chinese PCB services). But I guess if you only need access to the Uno-era Arduino pins, you can now fit everything into a ~4.4cm long double header. But it's a double header, so you can't make your 'shield' able to pull double duty by plugging directly into a breadboard, which you could have if there had been two close rows of 5V headers instead of a single double-row.
But it is an improvement, and the form factor does have a history of working, a single double-row header is the basis for the entire Pi-Crust/Plate/Shield ecosystem.
High-resolution photos at http://e2e.ti.com/blogs_/b/toolsinsider/archive/2013/10/03/i...