My adventure with ESP8266 (2/2): flash it!

Introduction 
The first part is here and it is about:

• hardware
• software
• firmwares
• nodemcu

It contains important information to understand this part.

Wirings
This table show how to connect the hardware together:

Pay attention to GPIO0, you need it connected only for flashing.

Flashing!

It's time to flash the device with a new firmware using esptool.

I decided to flash a nodemcu firmware.

Connect the GPIO0 to GND and than power on the device.

On my installation on OSX I did this command to flash the device:

python esptool.py -p /dev/tty.usbserial write_flash 0x00000 nodemcu_21072015.bin

If everything is ok, you should see this message:

Power off the esp8266 than remove the GPIO0 connection and than power on the chip again.

Talk with ESP8266
Now, it's time to talk with the chip.

I use kermit with this .kermrc configuration:

set carrier-watch off
set line /dev/tty.usbserial
set speed 9600

than you can press "c" to connect and typing print ("hello"); you should see the device responding hello back.

Now you can test some commands.

If you have downloaded the luatool, you can write your programs in a text file with lua extension and upload on the board with

python luatool.py --port /dev/tty.usbserial --src main.lua --dest main.lua --baud 9600

Lua files
Now, you can connect to the esp8266 and type dofile("main.lua"); to run the program.

If the file you are loading on the device, it is called init.lua the esp8266 at every boot will load it: pay attention, a bad init script can block the device forever... The only solution in this case is a re-flash of the device.

If you have any question, feel free to ask in the comments section.

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my wirings :)