The instructions below are based on my experiences whilst upgrading my ESP8266 module to firmware version 0.9.2.2

Connect your ESP8266 module as follows:

• Vcc = 3.3V (needs around 300-400mA peak)
• Gnd = -ve ground
• CH_PD = Chip enable so always +ve
• RST = Leave floating or ground to reset
• GPIO0 = Normally floating but this needs to be grounded when you start the update.
• UTXD = Tx data connect to Txd on FTDI/Serial interface
• URXD = Rx data connect to Rx of FTDI/Serial interface

You also need to download the new firmware and update tool from ElectroDragon: http://goo.gl/uHM6aO The firmware tool is called XTCOM UTIL.zip

Before you start the update, make sure your ESP8266 is working normally as follows:

1. Connect-up as above but leave GPIO0 floating.
2. Access the serial interface with a terminal program such as PuTTY.
3. Set the terminal s/w baud rate to either 57600 or 115200 (depends on whether you have an early or later model). The CoolComponents models are 115200.
4. Power-up the ESP8266 and you should see some readable text indicating that it's ready. If you get nonsense try changing the baud rate.
5. If all is well, try some AT commands.
6. Try AT+RST which should re-start the module.
7. Try AT+GMR which should give the firmware version.
8. NB: When entering AT commands there are no spaces!

If all is well you can move on to the firmware update.

Here are the steps required to update the firmware:

1. Put the ESP8266 into firmware update mode by grounding GPIO0 and re-cycling the power.
2. Launch XTCOM_UTIL.
3. In the Tools menu choose Config Device and set the Com port and set the baud rate to the value you used during testing (57600 or 115200). Click Open but don't close this panel.
4. From the API TEST(A) menu choose Flash Image Download and browse to the downloaded firmware .bin file
5. Click DownLoad to start the update - the progress bar will confirm it's under way.
6. That's it!

On completion of the update, disconnect GPIO0 from ground and re-cycle the power. You can now use the serial connection to try a few AT commands. NB: Following the update the default serial baud rate changes to 9600 and AT commands require a CR/LF combination to enter commands.