ESP8266 Community Forum

- Tue Nov 07, 2017 11:11 am #71608 Hello all! First, I know everyone is going to say "check out the internet"... and I have. The issue is that many of the videos and tutorials have conflicting information and much is not clear. I have followed many of them and have been unsuccessful in connecting my ESPP8266. Here is what I have found so far.

3V3 --> VCC
RST --> GND
EN --> VCC
TX --> RX
RX --> TX
IO0 --> GND (ground for programming / 3.3V for firmware booting)
IO2 -->
GND --> GND

Certainly correct anything I have above.

RST: Much information is conflicting here. My assumption from past experience is that connecting this to 3.3V will reset the board. Can someone confirm?

RX/TX: I am currently connecting this to a sparkfun FTDI basic board. My RX--> TX and TX--> RX. I have seen many tutorials that swap these. Can someone confirm the connections to a FTDI sparkfun basic

GND: I have tried to connect the FTDI ground directly to GND on the ESPP8266. I have read there have been issues with this and that you need a common ground. I have added a separate 1A power supply @ 3.3V. I have removed the ground from the FTDI and only used the PS one as well as making a common ground between the FTDI and PS.

VCC: I have used the FTDI PS. I have read there may not be enough power to run the ESPP so I opted for the power supply to provide the 3.3V.

Now it is very possible that I have a bad ESPP8266, but I wanted to confirm that the above assumptions are correct. At this point I have never had the ESPP8266 light up to indicate power. I have another one ordered incase this is bad.

If I could get confirmation on correct hookup for normal operation, then I can make the assumptions for firmware and TX/RX.

Appreciate the help and patience.

- Tue Nov 07, 2017 11:23 pm #71624

RST --> GND

...

RST: Much information is conflicting here. My assumption from past experience is that connecting this to 3.3V will reset the board. Can someone confirm?

Nope, that's your issue... RST needs to be pulled high for the chip to work.
The reset line on pretty much any microcontroller is active low, so if you pull it to ground, the chip will be in reset.

Also GPIO2 should be pulled high for best practice and GPIO15 (if available) needs to be pulled low.

- Wed Nov 08, 2017 1:59 am #71634 So I addressed your mentions and still no luck. A few items that I can note though:

1. When I power the device I never get the red LED to show the device has power. I see the blue LED flash once and then go out.

2. Occasionally, I was getting the following error when I tried to upload the blink example

Sketch uses 222205 bytes (51%) of program storage space. Maximum is 434160 bytes.
Global variables use 31572 bytes (38%) of dynamic memory, leaving 50348 bytes for local variables. Maximum is 81920 bytes.
warning: espcomm_sync failed
error: espcomm_open failed
error: espcomm_upload_mem failed
error: espcomm_upload_mem failed

3. In some cases, I would get the blue LED to blink when the Arduino sketch was uploading. When I removed the GPIO0 from ground and re-powered the device, the sketch did not run.

Some other items. I have tried using the VCC and ground from a sparkfun FTDI basic as the powersource. I also have been using the + and - from a separate power source as an alternate. Neither has been able to provide the RED LED ON for power status.

Is there a simple way to just get the RED LED on to show it is receiving power correctly? I have to be missing something simple here.

Just a recap

3v3 --> I run this directly from the FTDI basic into a BB
RST --> Jumper from 3V3
EN --> Jumper from RST
RX --> Runs to TX on FTDI
TX --> Run to RX on FTDI
IO2 --> Jump from 3V3 from BB
GND --> Directly from FTDI ground
IO0 --> Jumper from Ground only when uploading, unplug when I am ready to run

- Wed Nov 08, 2017 8:43 am #71639

RX/TX: I am currently connecting this to a sparkfun FTDI basic board. My RX--> TX and TX--> RX. I have seen many tutorials that swap these.

To use an Arduino Uno like board as the USB to serial converter the connection labeling is confusing. Rx-Rx and Tx-Tx. (and level shifting if a 5v board)

Using a USB to serial converter then it is Tx-Rx and Rx-Tx, and 3.3v signal levels.