I'm looking for a full size shield for the mega that I can use to remap the pins so subsequent shields work as they should.
Effectively it needs to be a prototyping board that doesn't have to sit on the top.
Does anybody know of such a shield? It seems a fairly simple concept! In particular I wish to use a data logging shield which has an SD reader and RTC.
I also would like to know if there are any shields or neat ways of attaching screw terminals to every pin on the mega. I've thought about using an old IDE cable and male-male header pins.
Mayhew Labs produced a 'go between' shield for the UNO footprint that enables you to redirect the pinouts. Obviously this wouldn't handle all the Mega pins, and I don't know of an equivalent for the Mega, so I don't know whether it will solve your problem.
That looks fantastic- unfortunately it doesn't help my predicament as I need to rewire to pins the Uno doesn't have! (namely 50-53) for SPI.
The other use is to use other UART's since the mega has 4, but only ONE of these would be covered by the Uno go between- so again this would unfortunately not work!
The sheer number of pins would make the exact same product too big for the mega impractical- but If it just had one solder pad per pin, I'd be able to solder some neat cables on for the remapping.
You mean you want a board so older Arduino shields that use D11-D13 for the SPI will work on a Mega or Leonardo? You could use a standard Uno-sized proto shield for the go-between if you use the ICSP pins to access the SPI data lines instead of D50-D52. There are a few available that have the ICSP connector included. Here is one for the Uno/Mega R3. http://store.nkcelectronics.com/Protoshield-KIT-for-Arduino-UNO-R3_p_308.html?redirect=1
The SPI data lines are duplicated on the ICSP connector and D50-D52 on the Mega. The Leonardo has the SPI on the ICSP only.
I don't remember where I saw it, but I have a vague memory of seeing an adapter that consisted of a narrow PCB for each header that had header pins sticking down and header sockets sticking up, offset by a couple of tenths of an inch. I think the idea was similar to the Mayhew Labs one - there was some scheme to map the connections between the two headers, perhaps using wire wrap. I should be possible to make something like that up for yourself if you wanted - just using 0.1" stripboard and generic headers with some sort of wired/wire wrap connections.