problem to upload a sketch in SONOFF POW - ESP8266

Using Arduino IDE 1.x
1

I have a problem to upload a sketch to my SONOFF POW.
Tried to upload the sketch OTA-mDNS-SPIFFS but without success.

REF:
[ https://www.youtube.com/watch?v=GoQXOLB50HA ]
#32 Internet of Things with ESP8266 #4: Upload Programs Over the Air (OTA)

My goal is to succeed with this POW based on this tutorial "#99 Measuring Power, hacked Sonoff POW, MQTT, Adafruit.io and Home Automation - https://www.youtube.com/watch?v=hv_FpBqWFrg"

https://drive.google.com/open?id=0B_vGp6rdca--a29UdktWU20yc3c – online directory
There is an online PDF available, online readable
https://drive.google.com/open?id=0B_vGp6rdca--YTc1VTluUVMwY1U in the hope to make it easier and more accessible.

Information about the connections between SONOFF POW and USB-SERIAL

How to select/activate ESP8266 in the IDE and adjust the correct settings (what I hope, these I found back in other tutorials )

This is the output which I get when I try to upload OTA-mDNS-SPIFFS

Arduino: 1.6.12 (Mac OS X), Board: "Generic ESP8266 Module, 80 MHz, 40MHz, DIO, 115200, 512K (64K SPIFFS), ck, Disabled, None"
OTA-mDNS-SPIFFS
...
Sketch uses 291,933 bytes (67%) of program storage space. Maximum is 434,160 bytes.
Global variables use 35,716 bytes (43%) of dynamic memory, leaving 46,204 bytes for local variables. Maximum is 81,920 bytes.
warning: espcomm_sync failed
error: espcomm_open failed
error: espcomm_upload_mem failed
error: espcomm_upload_mem failed
2

alex_golotte

espcom errors tends to be the RX and TX lines swapped.
Should be RX to TX and TX to RX.

Its not really an Arduino so maybe the sonoff forums may be a little more help ?