Do we have a hardware compatibility list anywhere which documents which shields work (or more importantly don't) with other shields? For example, my ethernet shield (the standard one) won't work with the nuelectronics colour LCD shield - for two reason, first it won't even physically fit right and second, the pin conflict means the display won't work without a lot of pcb hacking and software rewriting.
I wish there was a list where we could refer to so people don't make the mistake like I did and buy shields that won't work together.
Does anyone know what LCD shields will work with the WiShield and standard ethernet shield? I think the S65 shield will work with the ethernet shield, not sure about WiShield, I'd prefer to be wireless.
So many different shields made by so many different firms, I would think that keeping a current list up to date would be quite a task.
The best I could offer is that one should research what pins any specific shield uses Vs any other shield one has or wished to use.
Actually the whole concept of shields doesn't lend it's self real well to use them as multi building blocks. They are great to use for prototyping new software for single devices, but the problems of pin conflicts, total power consumption, etc makes them rather awkward to use that way.
Interesting topic and I'm sure others would have more insite then me on the subject.
The playground is a wiki; maybe an HCL type list could start there.
I've noticed a few issues crop up (on the forum, not so much personal experience) because sometimes a shield designer doesn't give much thought to sharing the arduino with another shield. For example, almost every shield with an SPI peripheral uses pin 10 as slave select.
Sometimes there are mechanical issues. IIRC, the RJ45 jack on the ethernet shield is taller than the stackable headers. You certainly wouldn't want a display to be anywhere other than on top of the stack.
ctually the whole concept of shields doesn't lend it's self real well to use them as multi building blocks.
Sorry, I have to disagree.
Depending on the application, I think well designed shields work quite well as modular components of a system. I've encouraged some of our students to do exactly that. I have even recommended that, instead of designing custom application-specific PCBs, they design a custom shield, so that the design or the module itself can go on the shelf, available for the next project or the next student. (This has not yet occurred. )
Most power problems I've encountered go away once I switch from USB to external power. The Arduino's power supply is hefty enough, IMO, for sensors, flash, etc. If you drive other things (large LED arrays, motors, etc), you'll need to make arrangements for additional power.
I can understand your opinion and don't totally have a problem with the shield concept, it can be a neat setup with a little luck. It's just that using stacked shields from different vendors often leads to pin conflicts and physical fit problems, and not every shield can to the top shield ;).
If one is building their own shields then that problem kind of resolves it self through proper design decisions.
