esptool issue (DTR and RTS signals)

Submitted by massimiliano on #1

Hi,

I’m facing an issue with placing an ESP32-C6 into download mode, which is done by manipulating the DTR and RTS signals. I attempted to set the compression threshold (on both the server and client) to 9999 bytes, but it didn’t resolve the problem. I even purchased a license in order to install the optimized build (I’m using a Raspberry Pi 3 B+), but that didn’t help either. When I try to manually manipulate the signals (I'm using IO Ninja), I can successfully control the RTS signal, but not the DTR signal. Interestingly, when used locally on the Raspberry Pi, both signals work correctly

Submitted by massimiliano on Sun, 2024/12/22 - 08:04

#2

I did some more test and when I get to toggle DTR the output from the serial port is not fully forwarded:

Raspberry pyserial-miniterm

--- RTS active ---
--- DTR inactive ---
ESP-ROM:esp32c6-20220919
Build:Sep 19 2022
rst:0x15 (USB_UART_HPSYS),boot:0x76 (DOWNLOAD(USB/UART0/SDIO_REI_FEO))
Saved PC:0x4080d588
waiting for download

 

macOS IO Ninja

ESP-ROM:esp32c6-20220919
Build:Sep 19 2022

Submitted by Michael on Mon, 2024/12/23 - 06:10

#3

I am away for a week but will investigate when i get back

Submitted by massimiliano on Mon, 2024/12/23 - 06:23

#4

No worries thanks. If you need I can let you connect into my setup

Submitted by Michael on Sun, 2024/12/29 - 11:32

#5

Im back from holiday, can you email me mail [at] virtualhere.com (mail[at]virtualhere[dot]com)

Submitted by fbo on Mon, 2025/09/15 - 03:11

#6

Was this resolved? 

I have the same problem that a change of the DTR signal is not propagated.
The USB-UART Chip used is a CP2104.

Submitted by massimiliano on Mon, 2025/09/15 - 06:46

#7

Unfortunately not

Submitted by Michael on Mon, 2025/09/15 - 07:41

#8

You need to use a windows or a linux client

Submitted by fbo on Mon, 2025/09/15 - 17:16

#9

I am.
Server is running on a Raspberry Pi, Client is on Windows 11 (Version 5.9.3).

Submitted by fbo on Wed, 2025/09/17 - 03:43

#11

Thanks for the hint. I updated to v11.4.0 of the driver and now both pins are being toggled.
However you still cannot get the ESP32 into boot mode. 
My first guess is that even though DTR and RTS pins are toggled right after another, on the actual pins there's a delay which causes the problem.
I played with the compression threshold on client side a bit, without any luck.

Submitted by Michael on Wed, 2025/09/17 - 07:59

#12

If there are extremely tight timing requirements for the reset, then it might not work because the packet cant get over the network fast enough. (You must use Ethernet for the virtualhere network connection, not WiFi)