User Manual

The m3pi expansion kit includes three pushbuttons that can be used to add a power button and

two general-purpose user buttons to the m3pi expansion PCB. The locations for these buttons are

shown in the two diagrams at the top of this section. See Section 4.c for more information about the

pushbuttons.

Serial Jumpers

If you want to be able to connect the serial lines of an XBee or Wixel wireless module directly to the

serial lines of the 3pi base (e.g. to use the Wixel as the m3pi’s main controller or to make the m3pi

a serial slave to a remote device), you should solder the three included 1×2 0.1″ male headers to

create the serial jumpers shown in the two diagrams at the top of this section. Be sure to solder the

short ends of the headers to the PCB so that the full extent of the long ends protrude up. The included

shorting blocks can then be placed over the protruding header pins to establish the alternate serial

connections. See Section 4.a for more information about the serial jumpers.

USB A Connector

The m3pi expansion kit includes a USB A header that lets you connect USB devices to your mbed

if it is programmed to act as a USB host. Please note that when installing the USB A connector, the

two large protrusions from the case must be soldered to the PCB along with the four logic pins. These

large protrusions provide structural support for the connector when they are soldered into the large

holes in the PCB. The location for the USB A connector is shown in the two diagrams at the top of this

2. Assembly Page 13 of 39