Arduino flasher 3.3v

Introduction

This explains how to:

• Easily lower the voltage of an arduino
• Use that arduino to flash a coreboot image on a GM45 Thinkpad with a SOIC16 chip

It requires:

• An AVR Arduino at 5v
• An USB<->Serial adapter capable of providing enough current to power up:
  • The arduino
  • The flash chip
  • The circuits around the flash chip

It was tested with:

• An Arduino.org "nano version 3.3"
• A Sparkfun "FTDI Basic 3v3" (Uses an FTDI FT232R)

HOWTO

• Flash the Arduino with frser-duino and lower the serial port speed to 115200

# make u2
# BLBAUD=57600 SERIAL_DEV=/dev/ttyUSB0 make program

• Connect the FTDI adapter to RX and TX of the arduino
• Connect the 3V3 of the FTDI adapter to the 5V pin of the Arduino
• Connect the GND of the FTDI adapter to the GDN of the arduino.
• Get an USB cable and don't connect it to the computer
• Connect it to the FTDI adapter
• Connect the clip (Like a SOIC-8 or SOIC16 Pomona clip) to the arduino
• Connect the USB cable to the computer.