ESP8266 Community Forum

- Fri Dec 18, 2015 4:55 am #36708 Hi guys,

i know there is on web tons of information how to connect ESP8266 board to Arduino or someTTL UART board, but there are different opinions and tutotials and most of them doesnt work. Basic connection is:
arduino/TTL board <==> ESP8266
GND <==> GND
RT<==> TX
TT<==> RX
VCC (3,3V) <==> VCC
When I connect only this 4 pins, red led is turn on and my system recognize there is something connected on new port, but serial communication is not available (because CH_PD pin is not connected). But when i connect CH_PD to VCC 3,3V red led comes off and also device disappear from device manager. (actually this worked for me for about half of hour, but then it stopped working). I have read I need to connect all these (CH_PD, RST, GPIO0, GPIO2) pins to VCC. On other page i read I cant connect any GPIO to VCC because by default is GPIO set to digital output. I found also comment i need just connect GPIO to GND. Long story short...i found a lot if different hints which are saying opposites to some other hints/tutorials. Can someone please explain how it should be connected and why, I dont want to break ESP board because of some wrong tutorial. It would be really helpful for other newbies like me which are lost in all not working tuts. Thank you all for any reply.
ps: i dont use power converter because i use 3,3V arduino, or 3,3V TTL UART (what i have read so far its not needed)

thanks
Lubo

- Fri Dec 18, 2015 1:24 pm #36729 disappearing from device manager usually means that the usb device is malfunctioning. Possibly because it's internal 3.3v regulator is overtaxed.

the esp chips really do require a lot of power for their small size.

Use a power converter. lm1117-3.3 devices work very well for this job. You will want to feed 5v (from usb or external power) to the input pin on the 1117.

As for the rest, you didn't say which esp board you have. There are a lot of them, and some of them have built-in pull-up resistors, others don't. So, tell us which one you have and we can help you with whether you need to connect things to 3.3v or ground.

Also it's usually a good idea to use a pull-up resistor when you apply 3.3v to those pins. 3.3k 1/4w resistors are what most people use.

- Tue Jan 05, 2016 4:04 pm #37993 Hi thank you for your quick reply, unfortunately i had an accident and i spend my Christmas in hospital. I just got back and i was playing a bit with ESP8266 again but with no luck. My model is ESP-01 powered up by MC33269DT regulator (output is 3.3V 800mA), RX and TX are connected to Arduino nano, CH_PD and VCC pins are connected to 3,3V, GND to GND, and i tried with and without GPIO 0 to GND connected. In Arduino IDE 1.6.5 with ESP8266 board manager installed I open serial monitor and i get there message "radio init fail" . Big thank you for your support.

- Fri Jan 08, 2016 5:37 am #38194 Both GPIO0 and GPIO2 must be HIGH for the ESP to boot into the firmware.