Connecting to UDOO Neo serial console

Introduction

This post explains how to connect to the Cortex-A9 debug serial of your UDOO Neo to control the U-Boot bootloader, watch your Linux kernel boot, and eventually get a login.

Reference

• See http://www.udoo.org/docs-neo/Hardware_&_Accessories/Uart_serial.html
• UDOO_NEO_schematics.pdf - UDOO Neo Rev.D2 (JUL-2015) Schematics

Required material

• One UDOO Neo Full
• One 8GB microSD Card formatted with a bootable image for your UDOO Neo
  • Example: UDOOBuntu_neo_v2.0beta3
• One USB-to-TTL Serial Cable (3.3V level)
• One 10-mil male-to-male pin header strip
• One laptop with a terminal emulator installed
  • Example: PuTTY on MS Windows
• A 5Vdc power supply for your UDOO Neo
  • Tested withh a USB battery pack plus a USB to Micro-USB cable

UDOO Neo - Cortex A9 Serial Debug Configuration

• Connect to UART_1 (Cortex A9 serial debug)
• Serial Port Parameters: 115200,8,n,1

Wiring Diagram

Connect the TTL-level pins of the USB-to-TTL serial cable to your UDOO Neo as follows:

Detail on UART_1 connections

Trying UDOOBuntu_neo_v2.0beta3 - Step-by-step instructions

• Format a 8GB MicroSD Card with Udoobuntu2_beta3
  • Follow the instructions at http://www.udoo.org/get-started-neo/
• Plug the MicroSD Card into the MicroSD slot of your UDOO Neo
• Connect the USB plug of the USB-to-TTL dongle on your laptop
• Identify the serial port that is exposed by the USB-to-TTL dongle on your laptop
  • I.e. on MS Windows: Start > Computer > Properties > Device Manager then look under "Ports (COM & LPT)"
• Start the terminal emulator on your laptop (parameters: COMxx:115200,8,n,1)
  • For convenience you may create a logfile of the data exchanged on the serial console
• Power-up the board by plugging the Micro-USB cable of the battery pack into the Micro-USB connector of your UDOO Neo
• Watch the U-Boot and kernel boot messages on the serial console

Sample logfile: 20151107-1106-udoobuntu2_beta3-udooneo.txt