What is MTrain

The MTrain is a new devboard based on the Cortex M7 being developed by RoboJackets to replace the Mbed in our robotics applications. The MTrain has many advantages over the Mbed, most notably:

• Hardware Floating Point Unit
• 256 MB of Flash Memory
• 256 MB of RAM
• JTAG support
• Ability to support Over the Air Firmware Updates
• High Speed USB (480 Mbps)
• 100 Mbps Ethernet

4180 Project

For the 4180 project we have implemented the API for DigitalIO and I2C on the MTrain. Our demo specifically connects a pushbutton to an led through the MTrain to demonstrate the DigitalIO while also sending Hello I2C! over the I2C line to an Mbed which then displays it on the LCD screen.

Code

MTrain

The code that runs on the MTrain can be found in the repo connected to this website or by following this link The specific code that was written for this project can be found in the following locations:

• DigitalIO
  • Headers
  • Source
• I2C
  • Headers
  • Source

Mbed

The code that runs on the Mbed can be found in the Mbed repository here

Demonstration Setup

Software Setup

MTrain

1. Clone the repo with our code found here
2. Connect the MTrain over JTag using the adapter
3. Flash the MTrain by running make test-communicate_i2c-prog from the mtrain-4180 folder

Mbed

1. Build and download the project found here
2. Copy the bin file to the Mbed over USB

Hardware Setup

Requirements

• 1x Functional MTrain
  • The pcb and other necessary production information can be found here
• 1x Mbed
• 1x LED
• 1x Pushbutton
• 1x uLCD-144-G2
• 1x Breadboard
• 1x JLink Segger and JTag adapter (For flashing the MTrain)

Setup

Ground

• Connect the Ground lines of the Mbed and the MTrain to the Ground rail of the breadboard

  I2C Lines

• Connect pin 25 on the MTrain to pin 10 on the Mbed
• Connect pin 26 on the MTrain to pin 9 on the Mbed

  Pushbutton and LED

• Connect pin 3 on the MTrain to one side of the pushbutton
• Connect the other side of the pushbutton to the LED
• Connect the other side of the LED to ground

  LCD Screen

• Connect +5V on the LCD screen to the VU pin on the MBed
• Connect Ground on the LCD screen to the ground rail
• Connect pin 30 of the Mbed to the reset pin of the LCD screen
• Connect pin 28 of the Mbed to the TX pin of the LCD screen
• Connect pin 27 of the Mbed to the RX pin of the LCD screen

  USB Power

• Connect the Mbed to USB power first
• Connect the MTrain to USB power

Results

If everything was done correctly pushing the button should turn on the LED and the LCD screen should be repeatedly flashing Hello I2C! as shown in the video below: