Geekcreit® USB To ESP8266 Serial Adapter Wireless WIFI Devel
Posted: Thu Jul 25, 2019 7:32 amUpdate 8 October 2019.
Following advice received and further experimentation I have answered my own questions in post #8.
The reported voltages do no harm and the upload was affected by a power issue.
For details see post #8
Thanks for all your help
Original question
Hi there,
I have some experience with the Arduino, but this is my first attempt using the ESP8266. I purchased
Geekcreit® ESP8266 ESP01 WIFI Transceiver Wireless Module + USB To ESP8266 Serial Adapter Wireless WIFI Develoment Board from Bangood.
I purchased multiple ESP8266 ESP01 WIFI Transceiver Wireless Module and a single programmer.
I have 2 questions.
1. I measure the following voltages
on the pins of the USB To ESP8266 Serial Adapter . There are many warnings on the web that the ESP8266 does not tolerate 5V. Is the 5V on the RX GPIO3 of concern?
This module works properly when I connect TX to RX. The Serial monitor in the Arduino IDE faithfully echos all characters.
Here are the voltages:
2. How to load a sketch?
I think I confuse the term "Flash" with "Loading a sketch"
I use the Arduino IDE. When I plug in USB-UARTESP8266 combo I pull GPIO0 to ground as described by Arjun SK here. Then I attempt to load the default sketch:
but the upload fails with "esptool.FatalError: Failed to connect to ESP8266: Timed out waiting for packet header"
On the other hand, The wiki, in article All in one ESP-01 to USB converter suggest that GPIO0 is pulled down when you want to update the firmware. Not when you want to load a sketch.
I assume the wiki is correct. And I should be able to upload a sketch without any trickery. is that correct?
Thanks for reading this far. Looking forward to your answers.
Bram van Oosterhout
Following advice received and further experimentation I have answered my own questions in post #8.
The reported voltages do no harm and the upload was affected by a power issue.
For details see post #8
Thanks for all your help
Original question
Hi there,
I have some experience with the Arduino, but this is my first attempt using the ESP8266. I purchased
Geekcreit® ESP8266 ESP01 WIFI Transceiver Wireless Module + USB To ESP8266 Serial Adapter Wireless WIFI Develoment Board from Bangood.
I purchased multiple ESP8266 ESP01 WIFI Transceiver Wireless Module and a single programmer.
I have 2 questions.
1. I measure the following voltages
on the pins of the USB To ESP8266 Serial Adapter . There are many warnings on the web that the ESP8266 does not tolerate 5V. Is the 5V on the RX GPIO3 of concern?
This module works properly when I connect TX to RX. The Serial monitor in the Arduino IDE faithfully echos all characters.
Here are the voltages:
Code: Select all
Pin --------------Voltage to GND----------------
without with ESP8266 plugged in
Vcc 3.3V 3.6 3.6
RST 0 2.8
CH_PD/EN 3.6 3.6
TX GPIO1 3.6 3.6
RX GPIO3 5 5
Flash GPIO0 2.4 2.4
GPIO2 2.4 3.6
GND 0 0
2. How to load a sketch?
I think I confuse the term "Flash" with "Loading a sketch"
I use the Arduino IDE. When I plug in USB-UARTESP8266 combo I pull GPIO0 to ground as described by Arjun SK here. Then I attempt to load the default sketch:
Code: Select all
void setup() {
// put your setup code here, to run once:
}
void loop() {
// put your main code here, to run repeatedly:
}
but the upload fails with "esptool.FatalError: Failed to connect to ESP8266: Timed out waiting for packet header"
On the other hand, The wiki, in article All in one ESP-01 to USB converter suggest that GPIO0 is pulled down when you want to update the firmware. Not when you want to load a sketch.
I assume the wiki is correct. And I should be able to upload a sketch without any trickery. is that correct?
Thanks for reading this far. Looking forward to your answers.
Bram van Oosterhout
