MicroPython Forum (Archive)

i2c.scan() delivers me a list of the values 8 to 119...

>>>i2c.scan()
[8,9,10,11,12,13,14,15,16 - and so on - 117,118,119]

Found it - but after adjusting the potentiometer the problem was not solved :/
After turning the potentiometer high, the display shows me just a single row on the lcd:

For the pull up:
is this wiring ok?

(the lines to the bottom are the connections to the LCD... didnt fount the right module for fritzing)

I used 4.7k ohm resistors and 10k ohm resistors... but nothing worked?

On the backside of my LCD-Module there is a PCF8574T-Module... I thought this will do it?
Or are some resistors between the Module and the NodeMCU needed? How should I wire this? :/

How can I find out the right I2C address? Because I am using the same wiring on my NodeMCU VIN -> VCC GND -> GND D1 -> SCL D2 -> SDA and the same code from mcausers exampler, but nothing appeard on the LED... On some websites I read that the I2C address "0x27" can be wrong, and I have to try another...

ok, maybe I don't net a voltage divider for the AO on the NodeMCU. My first test was with a voltage divider R1 = 220, R2 = 100 and a potentiometer... and the highest value was 340... without any resistor the highest value is 1024. My wiring: NodeMCU -> potentiometer GND -> GND 3V3 -> Vcc AO -> Vout ...

Thank you very much! :) Further question: What about voltage divider? Can I use the voltage divider methode in any case? For example if I can not finde any information about the electric current... For red LED: Vout = Vin * (R2/(R1+R2)) Vin = 3.3V Vout = 1.7V => any two resistors with the same ohm w...

(Maybe a genearal question for all kind of boards) I read a lot of tutorials for the ESP8266. In some tutorials they used for wiring some kinds of resistors - in other tutorials they didn't use any resistors and only used direct connections to the board. First I thought it has something to do with t...

Noob-Question: I want to power the NodeMCU with my Travel USB-Adapter for my Smartphone. It is a "Samsung ETA0U81EBE" with the following specifications: Input: 100-240V Output: 5V, 1.0A Would this be ok for the NodeMCU? Or would you advise me from powering the NodeMCU with this Travel Adapter? Why? ...

It works!

After waiting a few seconds more I was able to use the REPL
Thank you very much