Trying to get started

[Roy J. Tellason]

A while back I bought some of these:

https://www.banggood.com/Geekcreit-ESP3 ... rehouse=CN

which as far as I can tell are a clone of this board:

https://github.com/SmartArduino/SZDOITW ... 66---ESP32

Initially I went through the process of adding ESP8266 and ESP32 stuff to my Arduino IDE, since that's what I have installed and handy. (I may go to something else later on, but...) My early attempts to use one of these boards after soldering the pins in weren't very productive -- the system didn't seem to see the board at all and I'm assuming now that what I had was a charging-only cable, perhaps. At this point the system sees the board, as evidenced by /dev/ttyUSB0 showing up in the list of available ports -- if it's not there, the system isn't seeing the board.

I'm not real sure about which board to select. The logical choice seems to be "ESP32 Dev Module" since that's what the board is calling itself and I'm not seeing any choices in the list that look more logical.

I have the board with pins soldered and in a breadboard, but am not sure as to what I might need to do to get this responsive. I see various people hanging caps, push buttons, and all sorts of stuff on there, but don't know what I need. I did follow some link that was supposed to give me a schematic of the board, but that got me a 404 error so at this point in time I'm not real sure about a lot of things, like what I need to do to set it up, what pin connects to an onboard LED, stuff like that. This link for schematics didn't work:

https://github.com/SmartArduino/ESP/blo ... rESP32.pdf

Trying to upload *anything* to the board seems to want to compile all over again even if I've just compiled the code in question. And I invariably end up with the same error:

AttributeError: 'Serial' object has no attribute 'dtr'

I did see a thread that mentioned this, and Debian (which is also what I'm running here), but the solution to that poster seemed to be something to do with a python file, and I'm not finding any python files here anywhere, unless somewhere or other it's tying into one and I don't know it.

Anyhow, I'd like to solve that particular issue so I can start to put some code on this thing, and I'd also like to acquire some more hardware info on this board if anyone knows where I might find some, or if youc can point me toward some specifics. Any help here would be appreciated.

[ESP_Sprite]

I seem to remember that very old versions of the Python serial library have this issue... perhaps update your Debian or your pyserial library? A quick Google also pops up this, perhaps it's relevant?

[Roy J. Tellason]

Maybe. I *did* find the python file referenced, it was in the directory ".arduino", which I hadn't looked in before. I did make the change suggested in that other thread, commenting out that one line, and now I get different errors:

Code: Select all

Arduino: 1.8.13 (Linux), Board: "DOIT ESP32 DEVKIT V1, 80MHz, 921600, None"

Sketch uses 198876 bytes (15%) of program storage space. Maximum is 1310720 bytes.
Global variables use 13276 bytes (4%) of dynamic memory, leaving 314404 bytes for local variables. Maximum is 327680 bytes.
esptool.py v3.0-dev
Serial port /dev/ttyUSB0
Connecting........_____....._____....._____....._____....._____....._____.....____An error occurred while uploading the sketch
_

A fatal error occurred: Failed to connect to ESP32: Timed out waiting for packet header


This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

I'm not sure what those dots and underscores mean offhand. I'm not sure if I even have this thing jumpered right, or if I'm supposed to be pushing any buttons here, or what...

[ESP_Sprite]

This usually means something hardware-related. Could be an auto-reset thing; especially if you commented out something to do with dtr, you likely broke the auto-reset functionality of esptool.py. Can you press and hold the 'boot' button, press and release the 'reset' button and finally release the 'boot' button while you see the '........____' characters, to see if it flashes then?

[Roy J. Tellason]

Pressing buttons apparently has something to do with it...

I found the text "Holding down Boot and then pressing EN initiates Firmware Download mode for downloading firmware through the serial port." and when I tried that, sure enough it worked! The board is now happily sitting there blinking for me.

I'd still like to know why it seems to want to compile something before uploading it even if I just compiled that same exact code.

[ESP_Sprite]

That I don't know. Cmake will usually give you some chatter before uploading as it needs to check if it actually *needs* to compile something (and the old Gnu make system is even worse at that), but you should not get a complete compilation pass every time.