ESP8266 Community Forum

- Thu Aug 24, 2017 10:35 pm #69444 I am using this ESP8266 model: https://www.sparkfun.com/products/13678 with an Arduino Uno.

It seems to be unused since people use more recent models, so I am having lots of trouble finding help.
Whenever I upload to it, I get this error:
1 - 1Archiving built core (caching) in: C:\Users\(myUsername)\AppData\Local\Temp\arduino_cache_499360\core\core_esp8266_esp8266_thing_CpuFrequency_80,UploadSpeed_921600_ae403b993bb39c8ed987052fb6352185.a
2 - Sketch uses 226733 bytes (52%) of program storage space. Maximum is 434160 bytes.
3 - Global variables use 31940 bytes (38%) of dynamic memory, leaving 49980 bytes for local variables. Maximum is 81920 bytes.
4 - warning: espcomm_sync failed
5 - error: espcomm_open failed
6 - error: espcomm_upload_mem failed
7 - error: espcomm_upload_mem failed

I added in the numbers so it's easier to differentiate between the lines. All the bolded lines are marked red (errors).

Things I have tried:
1) My RX and TX outputs work fine
2) My voltage is at ~3.3 coming from a power supply
3) The ESP8266 blinks blue for a second when turned on and never blinks again until I turn it on again
4) The board I have my IDE set to is "Sparkfun ESP 8266 thing"
5) Connecting "RESET" or "ENABLE" to 3.3v
6) Connecting GPIO0 to ground, turning it on, then unplugging it when the board connects

My connections are as follows:
VC -> 3.3v
GND -> GND
RX -> RX
TX -> TX

I really need some help figuring this out. Thanks in advance to any replies!

- Wed Sep 20, 2017 4:23 am #70136 Hihi,

are you sure you wired everything correct....???
You wrote:
My connections are as follows:
VC -> 3.3v
GND -> GND
RX -> RX
TX -> TX

So
RX ==> RX
TX ==> TX

I would expect wired as following:
RX ==> TX
TX ==> RX

...
???
-nikxha-

- Wed Sep 20, 2017 6:01 am #70140

are you sure you wired everything correct....???
You wrote:
My connections are as follows:
VC -> 3.3v
GND -> GND
RX -> RX
TX -> TX

That is how you would connect it to a board like an Arduino Uno. Now the problem with connecting it like that (if an Arduino board is used rather than a USB to serial converter) is that the signal levels are 5 volts and the ESP should only have up to 3.3 volts. One other thing that sometimes is missed is that the Uno's cpu must be held in a reset state.

The 5 volts coming into the ESP's RX pin can be reduced with a resistor voltage divider. The other problem is that you can not use the Uno's 3.3v to power the ESP. (again, assuming that is what is being done) It does not have enough current for the ESP.

http://electronut.in/an-iot-project-with-esp8266/

https://arduino.stackexchange.com/quest ... ut-shields

https://iot-playground.com/blog/2-uncat ... connection