espduino firmware loading on ESP8266 for MQTT

Hello,
I’m trying to load the espduino firmware on an ESP8266. I’m using a Raspberry Pi.

When I run the command:

esp8266/tools/esptool.py -p /dev/ttyUSB0 write_flash 0x00000 esp8266/debug/0x00000.bin 0x40000 esp8266/debug/0x40000.bin

I get this response:

Connecting…
Traceback (most recent call last):
File “esp8266/tools/esptool.py”, line 383, in
esp.connect()
File “esp8266/tools/esptool.py”, line 151, in connect
raise Exception(‘Failed to connect’)
Exception: Failed to connect

Has anyone tried espduino firmware?