This lab is testing serial capability.

In the first screenshot, I disable the console on /dev/ttyAMA0.

In the second screenshot, I use minicom to first display only characters I receive via loopback, and then I enable echo to see both what I send as well as receive.

SPI loopback test, successful

I don't have the ADXL345 nor BMP180, so I can't exactly test this. However, I was able to connect to an Arduino via a logic level converter to confirm that I2C in fact works.

I don't have the necessary hardware to perform these tests.