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

User avatar
By ArnieO
#62191 I just procured 2 x 2 ESP-01S on Aliexpress, and was surprised to see that I received two versions.
Both are on black PCB, and both have 1 MB flash memory (I checked with a sketch).

The one marked "ESP-01S" does not have a red power LED, only one larger, blue LED. It also has far more chip capacitors than the other one. And using the Arduino IDE, addressing LED_BUILTIN does not work. I found the LED to be connected to GPIO2, and not the usual GPIO1 = LED_BUILTIN. Loosing the red LED suits me fine, as I am working on a battery powered project and would remove it anyway.

The other black module is marked "AI-Cloud inside", and is closer to a "classic" (blue) ESP-01, it is similar but not identical in layout or number of chip component to some blue ones I have lying around.

I tried both to google for more information and search this forum, without much luck.

Has anyone else noticed this, and does anyone have knowledge about more differences between the versions than the blue LED?

Photo of the two versions:
Image
User avatar
By Manuel Barbosa
#76331 I have the same problem, recently revede 2 from the same seller and this is what I found out:

"Functionally - nothing. The modules are fully compatible in terms of connection, power supply, service, etc. ESP-01S as a newer version has a redesigned printed circuit board. The placement of the components on the surface of the plate changed slightly. The work stability has been improved, the range has been slightly increased. At the back of the tile there is a convenient "pull-off" for easy connection."

source: https://nettigo.pl/products/modul-wifi-esp8266-01s-podlacz-arduino-do-sieci-bezprzewodowej