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

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By Didier9
#2151 My ESP8266 module (the one with the 2x4 header and the PCB antenna) has two LEDs, a red one that looks to be just a power indicator (it is always on when power is applied) and a blue one that blinks during reset and when flashing the module.
Does anyone have a definitive answer as to what those are actually supposed to indicate?
Of course, I did not see any reference to them in the "documentation".
Thanks in advance
Didier
User avatar
By mamalala
#2183
Didier9 wrote:My ESP8266 module (the one with the 2x4 header and the PCB antenna) has two LEDs, a red one that looks to be just a power indicator (it is always on when power is applied) and a blue one that blinks during reset and when flashing the module.
Does anyone have a definitive answer as to what those are actually supposed to indicate?
Of course, I did not see any reference to them in the "documentation".
Thanks in advance
Didier


The blue LED is connected to the UART TX pin, the other one directly to the supply voltage. So you can't really control them individually. Well, you could with the blue LED, but then you would need to disable the UART TX on that pin and make it a regular output pin instead.

Greetings,

Chris
User avatar
By Didier9
#2185 Hi Chris,

Thank you for that! That makes sense and correlates with my observations.
I found out a link to a"generic" schematic but it did not show any LED.

As an aside, the module I have (version 1) seems quite sensitive. At my house, it consistently detects 7 access points (2 are mine). I have a big yard and the neighbors are not really close, so that's really good.

Didier