How to Configure a Programming Circuit for an ESP32 Module

In the video we look at how to design a circuit for programming an ESP32 module. We also explain the Strapping Pins on the ESP32 and how they work.

[trhosking]

1. Sender, in this case the PC, asserts RTS (Request to Send) to initiate handshake.
2. Receiver asserts CTS (Clear to Send) to indicate that it is ready to receive data.
3. Sender asserts DTR (Data Terminal Ready) for the duration of the transmission.
4. Sender transmits data continuously. The receiver may lower CTS during the transmission to exercise flow control.
5. Sender lowers DTR and RTS to end transmission.
6. Receiver lowers CTS.

[andychess]

Excellent video. Thank you for taking the time to explain this everyday topic that most of us take for granted. It was 25 mins of time well invested as I learned a huge amount.

[blakel]

Brilliant, been looking all over for help on adding USB programming like the dev boards have.

[mathieuegmann]

Very good explanation, thank you.
Regarding the mosfet, I would recommend the 2N7002.

[aboumohamed]

Good job. Well Explained and excellent video.
I was trying to program an ESP32 WROOM and was able; by using another ESP32 module (EN of the module is connected to GND) and connecting TX0, RX0 to the WROOM + 3V3 + GND.
EN of the WROOM had the resistor 10k to 3V3 with a 100nf to GND + push button to GND (RESET button).
GPIO0 of the WROOM is also connected to 100nf to GND + push button to GND (BOOT button).
To program, press both buttons, then release the reset button. ES32 will start uploading.

[chrispharaoh]

Very informative video, thanks a lot. I would love also if you would have put the whole schematic in one document

[BenM]

What a great explanation! Thanks for sharing!

[steinamrhein]

Hi, I just discovered your channel and am absolutely blown away. Super cool content and very well delivered! One question I have though, on the newer esp32 s2 and s3 they have a USB to uart chip already integrated in the chip (at least as far as I understand). How can I flash my software onto these? Do I also need to pull down GPIO 0 to do that or is this already implemented like you did in the internal USB to uart chip?

[scor]

These are not “simple” MOSFETs, cause the voltage is 3V3. Not many of them operate with such voltage on a gate.

[BuildandTinker]

Great video, thanks for taking the time to do this. Can you tell me what part no. you would recommend for the mosfets? Many thanks

[harmonygears]

Very good Video. Only thing which may was left out is that the ESP32 S series has build in USB. So in that case no UART converter is needed.

[Farismujkic-nc]

The video was well explained. However, I have a question. If we have uploaded our code and no longer need the USB connection to the computer, and at some point our device resets (either intentionally or unintentionally), IO2 has a low value, causing the ESP32 to enter boot mode, which we do not want. How can we resolve this issue?

[NemonicanatLarge]

As far as the mosfets - you have to use the type for digital circuits

[fabiosuriano]

Hi, what if I want to send keyboard data via uart? If I understand correctly RTS goes high and I enter in configuration mode even if I don't want to? Correct?

[mak]

Hi Tnx for covering the datasheet completely on this section, I used 2 transistors instead of MOSFETs in my design I used the esp32 chip directly that I'm starting to regret, because first of all it won't go into download mode, DRT and RTS are HIGH, I tried to used a jumper and 10K resistor for strong pull down, yet no luck same error:" Esp32 :No serial data received." The TX led on my design blinks when I try to upload the code but then I receive the error, upon further investigation I noticed that my chip has no internal flash memory, could it be the reason for the error?

[TheOldKid]

I bought an s3 wroom a few months back. Once it came in the mail i jumped on arduino ide and realized it wasn't one of their boards. After going to the venders sight for some info i found there wasnt much. After several failed attempts to get the camera going i threw it in a drawer. Lesson learned. Ill buy from more well known vendors. Freenova was a let down

[christy]

Strapping pins are advisable to use the Push button and LED??

[sepehrsaberi]

I hope you're doing well. As a developer interested in ESP32-related projects, I'm seeking guidance on how to program the ESP32 WROOM 32D using an ST-Link V2.

Could you provide some insights into this matter? I would appreciate it if you could direct me to useful resources, relevant instructions, or any tips that could assist me along this path.

Thank you very much,

[embetronix]

Can you name the MOSFETs which you have used?

[nelisbrink]

If the CH340C is powered by 3V3, does the chip have some internal circuitry to deal with the D+ and D- voltages at 5V? I can't find any more info on that, hoping you would have some insight?