Works great with a little soldering for use with an ESP8266 WiFi card.

Works great with a little soldering for use with an ESP8266 WiFi card.  Read Less

Great Item! Except Where can I get the firmware to reflash them. Do you have a website?

Great Item! Except Where can I get the firmware to reflash them. Do you have a website?  Read Less

I will increase star by one because seller is really trying to do the best. English is about broke and is really trying to hel...  Read More

I will increase star by one because seller is really trying to do the best. English is about broke and is really trying to help solve the problem even after I was refunded but I will not change my original post because I did get the ESP-01s and not ESP-01. He keeps insisting I use a 10k resistance when it isn't need. You probably just heard that from someone. Did you test it? I tested these and know what I have. So please be happy I am helping you get a 4/5. Here is my unbiased and truthful observations. Please stop emailing me about this item because posted below are details on how to program these for people who don't know.---------------------------------------------------First I did not receive the Esp-01, but the Esp-01s. So you may have too. I finally figured out how to program it and because a lot of people having problems I will post how I did it. I will attach image with how to connect it in programming mode and list instructions step by step.Programming Mode: FTDI - USBGuide to Programming:Buy an FTDI chip. (search FTDI USB to Serial) I don't like to advertise items or URL but people asked, so I use the one from HiLetGo FT232RL which has the 5v and 3.3v Jumper for easy voltage switching it is perfect for what I am doing because it was only 5$.Step 1. Connect ONLY the ground, RX, and TX to the ESP-01s (Only connect the VCC if you are using same FTDI as me and have tested the voltage to 3.3v with jumper in correct position.)Step 2. Use External power supply instead to VCC from the FTDI if you are unsure. Some fit on breadboard that do 5v and 3.3v or if you have the same FTDI I am using you can skip Step 2 and just use the correct 3.3v power supply jumper.Step 3. Connect GPIO0 to Ground. (This tells chip that you are going to be entering programming mode)Step 4. Connect GND to Ground.Step 5. Connect CH_PD and VCC to the 3.3v (Double check your voltage or you will burn chip up by applying 5v)Step 6. Plug In Everything. FTDI, USB, Power.Step 7. Briefly touch the RST (Reset) pin to the GND (Ground) and it will now boot into firmware flashing mode.Step 8. Go to the Arduino and get the ESP8266 Board Collection. If it doesn't show up in newest version 1.8.3 then, use older 1.6.5 and add the URL under preferences is what I had to do. (Google it)Step 9. Open Arduino IDE and go to Menu Tools> Board> Select the Generic ESP8266 Module.Step 10. Make sure baud rate is correct, same as setup under your Serial in Device Manager. Should be 115200 and set flash speed to 80MHz.Step 11. From Arduino IDE choose menu. File>Examples>ESP8266>Blink (not same as normal blink).Step 12. Upload/Flash the code to your ESP8266 and I hope this can help other people who are having problems.Step 13. Un-Ground the GPIO0 and Reset.Step 14. You are now booted in 'Normal' mode and your program you uploaded should be running.Enjoy! Let me know if you found it helpful.  Read Less