Sample Android Host
The Nexus 7 tablet is a good demonstration platform for OSP because of the easy access to the I2C bus and schematics. The following gives some information on the suggested hardware and software changes.
Depopulate the MPU6050 and AMI306 sensor chips. The relative locations of them are highlighted on the attached picture. Note the pin 1 orientation as they are rotated relative to each other. Footprints as seen from the top (per the respective datasheets) are shown. Signals of interest are highlighted. Note that no signals from the AMI306 are needed.
Locate and bring out the following signals (all signals are available on the MPU6050 solder pads):
- Pin 13 (VDD)
- Pin 18 (GND)
- Pin 8 (VLOGIC)
- Pin 23 (SCL)
- Pin 24 (SDA)
- Pin 12 (INT)
Note:
- Ensure I2C levels are set by VLOGIC not VDD.
- Do not apply additional pull ups on the I2C bus.
- Avoid drawing power directly from VLOGIC. Main power should come from VDD.
- Make the interrupt an open collector signal with a moderate pull up to VLOGIC (~4K7).
- I2C Bus 2
- MPU6050 I2C Addr: 0x68
- AMI306 I2C Addr: 0xe
GPIO_PX1 is the interrupt pin.