Flashing does not work <period>

[PatrickMans]

After a large number of attempts, spending 2 days with both claude and gemini (that eventually gave up on the matter), I still have not managed to get the software to flash, not even one pixel.
I am using a standard UART-TTL to USB adapter based on a CH340G chip (TLSR8359). That one has both DTR and CTS available so I figured I am good with that.
I hooked it up according to the wiring picture. I plugged in the USB adapter, which got recognized in my PC. I could open it without any problems. I created the firmware (makeit.exe) which went flawlessly. Then loaded that into the flashing tool.
As I understood I needed to unlock the flash memory prior to flashing the firmware, so I did. With this, the blue LED at the top right corner blinked and the webtool gave the message that all was OK and displayed DONE.
Then I started the flashing process, with which the blue LED flashed with every packet that was received by the hanshow. At the end of the flashing procedure there is a soft reset.
This is all I see happening on the flasher tool, but (apart from the LED) the display never changes.

I tried this with both windows11 and linux, with various displays and a number of USB/TTL adapters. I am kinda lost with this. Is there a kind of debug logging available to see what is happening?

[atc1441]

Hey, the flashing it TX only so there is no way of telling if everything is received by the TLSR side. So no further logging is possible/available.

Try to flash the new firmware I show here and do not select any type, the display should then be visible via BLE with "ATC_xxxxxx", no display or LED change will happen at that point, only if that works the flashing ok and you can try different display types.
https://youtu.be/9oKWkHGI-Yk

[PatrickMans]

I tried that several times but no luck. The display still refuses to show any other thing than was already on there. I managed to get a few displays that were already used so the shelf product is still displayed on there.
One thing I noticed is that where you talk about the DTR signal to the display, my USB-to-TTL adapter only has CTS and RTS. Serial (RS232) connections are not new to me so I assumed this would be the RTS signal on the interface. I also tested flashing connecting it to CTS but also that did not work. Does the flasher-tool take this (DTR and RTS) into account as well?

[PatrickMans]

Well... I got somewhat further in the trial and error process. Here is what I did so far:

• I changed the USB-TTL adapter from the CH340G-based one to a CP2102 device. This one did not have the DTR connection exported (like in your example) so I soldered on directly on the (very small) CPU of the adapter.
• I connected the display (Hanshow Stellar MN@ E31HA) and opened the port on the UART flasher part of the ATC_BLE_OEPL page.
• I loaded the firmware file directly from the flasher page.
• I unlocked the flash memory (don't know if this is still necessary, though).
• Clicked on the "write firmware" button to flash the firmware.
• At first it did not do anything after the flashing was completed. I then changed the device type to (16 - 213 HS BRW SSD).
• Redid the flashing.
• The display rebooted and the openEpaper page appeared, although with the big(ger) letters stating "No AP". The build information that was displayed stated "Apr 22 2026 12:12:40"
• Despite this, I tried to connect to the display using the ATC_ name but it just started searching and does not find anything. The BLE scanner on my phone connects within a split second and displays all the information.

So, the question is how to enable the AP and why my phone is able to reach it anyway, despite the No AP message.

Thanks!