ZumoCC3200Assembly

Zumo CC3200 Assembly Instructions

This page covers the steps required to quickly assemble the hardware, install the necessary software, and run a basic test of the Zumo CC3200.

Prerequisites

Getting a new Zumo CC3200 up and running is inexpensive and easy. For less than $130 in parts and with novice soldering skills, a Zumo CC3200 can be built in about an hour.

Hardware

1. RedBearLab CC3200 - the main CPU running your Zumo application
2. Zumo Robot for Arduino v1.2 - the tank frame, wheels, treads, motors, and sensors.
3. 2.54 mm male headers (e.g., these) - to enable easy access to the Zumo Robot's I/O pins
4. Soldering iron, solder, and two wires (e.g., two short male-male jumpers)
5. Four double A batteries

Software

1. Energia MT 17 (free) - to build and run apps that execute on the RedBearLab CC3200 motherboard
2. Processing 2.2.1 (free) - to run a host-side program that controls the Zumo CC3200

Hardware Assembly

Starting from the pre-assembled Zumo Robot for Arduino v1.2, there are just four steps to build a new Zumo CC3200:

1. Solder a row of headers to the Zumo shield that provide access to pins 5, 6, 9, and 10
2. Connect a wire between pins 5 and 9 and another wire between pins 6 and 10 (see picture below)
3. Unplug the Zumo reflectance sensor array from the bottom front of the Zumo
4. Plug the RedBearLab CC3200 atop the Zumo shield

Of these steps, only the first one requires any additional instructions. The approach detailed below ensures that the Zumo can still be used with standard Arduino Uno (though it'll be difficult to give up the CC3200's built-in WiFi support, 256K of RAM, 1MB of Flash, and 80 MHz CPU.)

Warning: Never use the Zumo reflectance sensor array when the RedBear CC3200 is connected to the Zumo; the sensors produce 5V signals that can permanently damage the max 1.5V analog inputs of the CC3200.

That said, it should be possible to leverage this sensor by

• only supplying 3.3 V rather than 5V to the array, similar to what was done for another Arm based controller here, and
• disabling or remapping the outer-most sensor connected to pin 5 (which must be used to drive the Zumo's motors when using the RedBear CC3200) as described in "Disabling or remapping sensors" (page 21) of Zumo Shield Users Guide

Soldering Headers to the Zumo

• Partially disassemble the Zumo(!)
• Solder a row of 2.54 mm male headers (e.g., these from Pololu) covering pins 5, 6, 9, and 10 to the Zumo shield
• Reassemble the Zumo

Disassembling the Zumo: Although counter-intuitive, the first step in assembling the Zumo CC3200 is to partially disassemble Pololu's pre-assembled Zumo Robot for Arduino. While the Pololu Zumo is available as a kit, it is far easier to partially disassemble a Zumo to add headers than it is to build it up from scratch. In fact, Pololu has done a great job designing the Zumo so that it can be assembled from a kit of basic parts and documenting how to disassemble it when necessary (e.g., to add headers for additional sensors or actuators.)

The excellent Pololu Zumo Shield for Arduino User’s Guide describes, in detail, how to assemble the Zumo from a kit and, on page 16, how to disassemble it enough to add new components. The disassembly process is summarized and lightly annotated below.

1. Remove the tracks from the chassis and carefully slide the two drive sprockets off the motor shafts.
   [The sprockets are very tightly attached to the motor shafts: the safest way to remove them is to place the sprocket in a small vice and gently tap the motor shaft with a 3/32 inch pin punch (or a small nail). In practice, it's unnecessary to completely remove the sprockets from the motor shafts; by sliding them just beyond the chassis, but still on the shaft, it's possible to separate the shield from the chassis. By not completely removing them, it'll be easier to restore the sprockets later.]

2. Remove the battery cover and batteries from the chassis.
3. Unscrew all four sets of machine screws and nuts holding the shield to the chassis.
4. Squeeze the negative battery terminal spring and gently ease both battery terminals out through the holes in the chassis. The motors will stay attached to the shield as it separates from the chassis.
5. Carefully bend both motors away from the shield to allow the front piece of the spacer plate to be removed.
   [both spacers will have to be removed to solder on new headers and, because they are almost but not perfectly bilaterally symmetric, you'll want to take careful note of their placement so that the reassembly process goes smoothly]

Reassembling the Zumo: You can reassemble the Zumo by following the disassembly procedure in reverse. Take care to replace the spacer plate pieces exactly as they were originally installed. Since they are not perfectly bilaterally symmetric, it's easy to mistakenly replace the spacers upside down.

The trailing edge of rear spacer has an extra wide notch on one side to make room for the "charge connector" header next to the on/off switch. Make sure the rear spacer sits perfectly flat between the battery case and the shield.

Software Installation

This section describes the minimum software installation steps required to build and run a basic test of the Zumo CC3200 robot.

1. Install Energia MT 17 (download): so you can create and build sketches that run on the Zumo
2. If you're using the Windows version of Energia, you must also
   • install the RedBearLab USB drivers (download): to enable Energia MT to download programs to the RedBearLab CC3200 and enable serial communications with the CC3200 via a Windows COM port
   • install the CC3200 Drivers for Windows (see the Energia 17 instructions under the "CC3200 LaunchPad" section of How to set up Energia on Windows for details)
3. Install Processing 2.2.1 (download): so you can easily create sketches that communicate with the Zumo via the WiFi

   Note: Be sure to download Processing 2.x not 3.x; many of the examples use libraries that have not yet been ported to Processing 3.x.

Troubleshooting

• If you're using Windows and Energia is unable to upload to the CC3200, make sure you've installed the CC3200 Drivers for Windows.

  If, after the install, Energia still can't upload then copy cc3200_drivers_win/i386/ftd2xx.dll into the folder containing Energia's upload program (cc3200load.exe): Energia_installation_folder/hardware/tools/lm4f/bin.

Basic System Test

After hardware assembly and installation of the software tools described above, the Zumo CC3200's basic hardware functionality can be demonstrated using a simple Energia MT sketch that communicates with a Processing sketch. Together, these sketches provide simple keyboard control of the Zumo's motors and real-time display the Zumo's accelerometer and gyro data.

Build and Upload the ZumoTest Sketch

1. Connect the Zumo to your PC with a USB cable
   • Switch the Zumo Bot's power switch to "off" (power will be supplied to the CC3200 via the USB connection)
   • Connect the RedBearLab CC3200 USB to one of your PC's USB ports
2. Unzip the Energia MT ZumoTest sketch zumo.zip, and double click the file ZumoTest/ZumoTest.ino.

   Note: the first time you double a sketch after installing Energia MT, Windows will ask you what program should open the sketch. Simply navigate to your installation of Energia MT and associate the exergia.exe program with .ino files.

3. Within the Energia MT IDE:
   • Select the RedBearLab CC3200 EMT board (via Tools > Board > RedBearLab CC3200 EMT (80MHz))
   • Select the COM port that's connected to the Zumo (via Tools > Serial Port > COM?)

   If you're using Windows, it's the "mbed Serial Port" that appears under "Ports (COM & LPT)" in the Device Manager.

   • Click the "Upload" button to build and upload the ZumoTest sketch to the CC3200.
4. Reset the CC3200 by pressing and releasing the RedBearLab CC3200's reset button.

Note: sometimes Energia MT has trouble uploading sketches to the RedBear CC3200. In these cases, it often helps to disconnect and reconnect the USB cable, and try to uploading again.

Connect to the Zumo CC3200 via WiFi

The ZumoTest sketch above starts it's own network, named "zumo-test" with password "password", that should be discoverable by your PC.

1. Connect your PC to the zumo-test WiFi network
2. Unzip the zgraph Processing sketch zgraph.zip, and double click the zgraph/zgraph.pde file.

   Note: the first time you double a sketch after installing Processing, Windows will ask you what program should open the sketch. Simply navigate to your installation of Processing and associate the executable processing.exe with .pde files.

3. Within the Processing IDE:
   • Click on the Run button to start running the sketch
   • Wait for the graph window to appear and type the letter 'c' to start continuous acquisition and display of accelerometer data from the Zumo

You should see three separate line plots of acceleration data, one for the x, y, and z axis. Any movement of the Zumo should be reflected in immediate changes to these plots. You can switch to displaying real-time gyro data by typing 'G' when the graph window has focus and switch back to the real-time acceleration display by typing 'A'.

You can also drive the Zumo CC3200 using the keyboard keys 'w', 'a', 's', 'd', and ' ' (space).

'w' - drive forward

'a' - turn left

's' - drive backwards

'd' - turn right

' ' - stop

See the zgraph/zgraph.pde file for additional keyboard commands.