Use this forum to chat about hardware specific topics for the ESP8266 (peripherals, memory, clocks, JTAG, programming)

User avatar
By trackerj
Nico van der Dussen wrote:Hi,

I'm new to the ESP8266

I want to use it with the Arduino IDE.

I have a CP2102 and a separate 3.3V power source (I tested - can deliver 500mA without voltage dropping)

Can I connect the CP2102 TX/RX/RST/DTR pins straight to the ESP8266 or must I use a 5V/3.3V level shifter?

I'm configuring the hardware according to the Minimal hardware Setup for Bootloading and usage on


If you take a look at the articles below you will find a detailed description with pictures of a CP2102 USB adapter that is working very well with ESP Modules. Despite the fact that ESP07 modules can be programmed and working OK using CP2102 Modules 3.3V power (at least the ones that I have had in my hand), I will suggest, for the sake of stability, to use a separate 500mA+ 3.3V PSU.

Cheap and Dirty Development Board - Ghetto Style
Firmware programming - ESP8266 Modules
Last edited by trackerj on Sat Jul 11, 2015 2:26 pm, edited 1 time in total.
User avatar
By Stoney
#23018 curious as to why you use the pulse circuit for the reset ?
all the commercial boards are DC coupled switches. it has always worked ok for me. is it just make button pressing easier ?

you can probably change your ftdi to output 3.3v instead of 5v by cutting a bridge and soldering a link. not sure on whether thats on all the ftdi's or just a few.
User avatar
By kolban
#23019 Howdy Stoney,
I'm not particularly skilled in electronics so it is very likely I could have made a mistake here ... however my thinking has been that when I press the button I want it to reset immediately ... and had no need for a "press and release" ... so the pulse circuit gives me just a single push for a reset.

What I would have liked to achieve would be a second button which would also pulse a reset while at the same time place GPIO0 low so that we would enter flash mode. However I haven't gotten around to experimenting in that area yet.

As for changing the output voltage of the USB->UART converters, that's a great tip and I'll look into whether mine can do that or not. I'm using CP2102's which I believe are different from what you mean when you say an ftdi?