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Resistors, Capacitors, Voltages, Oh My! (Flash ESP8266-12-E)

PostPosted: Wed Apr 08, 2020 8:37 pm
by undelusory
I'm trying to find out if I actually have what I need to flash my ESP8266-12-E, or if I need to buy some components or even a flashing "cape" (yeah, that's BeagleBone terminology, I have no idea why I used it).

I'm trying to follow this tutorial, particularly this circuit diagram:
Image

These are my questions so far (I may have more later):
  1. Can I use surface-mount resistors and capacitors? If so, how do I tell what capacitance a surface-mount cap is by the markings, and how do I use them in my breadboard? Solder leads to them?
  2. Assuming I can't find the right cap, what kind of substitutions can I make? Can the Farads be different, or just the Volts? Over or under?
  3. I take it from this that my pull-up and pull-down resistors can be anywhere between 10k to 100k (Ohms). Is it different for this board? I can't seem to calculate it myself without knowing more about the internal workings of the board.
  4. I have a 3.7V LiPo battery, is that close enough to use to power the board?
  5. Crazy shot in the dark, but can I skip the whole riot by buying a [url=]nano[] and attaching my board to it somehow to flash? if so, are the attachments one-to-one or how do I attach it?

Re: Resistors, Capacitors, Voltages, Oh My! (Flash ESP8266-1

PostPosted: Wed Apr 08, 2020 11:46 pm
by JurajA
did you consider to buy a development board like Wemos D1 or NodeMcu?

Re: Resistors, Capacitors, Voltages, Oh My! (Flash ESP8266-1

PostPosted: Wed Apr 15, 2020 6:53 am
by PCBEE
4: The datasheet says the max input voltage for the ESP8266 is 3.6v.
https://www.espressif.com/sites/default ... eet_en.pdf

That said, a fully charged LiPo will measure 4.2v, 3.7v is the nominal voltage. So you'll have to use a voltage regulator.

Re: Resistors, Capacitors, Voltages, Oh My! (Flash ESP8266-1

PostPosted: Thu Aug 20, 2020 12:48 am
by guysnraw
Answers for your questions
1. This circuit can be done on pcb so that you can program and test temporary
2. As far as capacitor needs, farad can be changed as per your need, volts can be higher but shouldn't be lower, I'm using 10uf 16v capacitor works without any issues. Too much higher farad reduces your battery incase if your concerned about long life of battery power.
3. I googled and read many tuto and found resistor for pull up/down can be between 1K to 10K. I used 10K.
4. It should work
5. Best is to use USB>UART (USB TO UART TTL 5V 3.3V FT232RL Download Cable To Serial Adapter Module For Arduino) 8-)