Arduino Noob here. I think once I get the hardware figured out I can start confusing myself with C code. :D
I have 3 sensors and a LCD shield with buttons. I board I am using is a Mega 2560.
Sensor 1) BMP180 - Has 4 pins. VIN, GND, SCL and SDA. From what I gather it is I2C compliant. I believe I need 3.3v power only to this chip.
Sensor 2) Labeled as GY-521. A 3 axis accelerometer and 3 axis gyro. Has 8 pins. VCC, GND, SLC, SDA, XDA, XCL, ADD, INT. From my reading, either 3.3v or 5v power is OK. Have not found much about this ship. I believe it is I2C compient as well.
Sensor 3) MAP sensor for a Chevy. This will be analog. Runs off of 5v power. VIN, GND and signal.
Display w/ Buttons) Uses 6 digital lines for the display and one analog for the buttons. Also have pins for RST, 3.3v, 5v, 2 GNDs and a VIN.
My question; How do I connect the bits? I know any pin can do in or out. Does it matter what pins I use for what? With 2 I2C devices, how does that work with only a pair of I2C pins? How about splitting power to everything with only one pin marked for 3.3v and one for 5v and a pair for GND?