"No Printer Attached" SKR E3 Mini V3.0 & TFT35 E3 V3.0.1

[LetMeFly96]

I've been down the rabbit hole here in ways I've never imagined. I am so new to compiling firmware that I feel like I'm in diapers again.

I have a SKR E3 Mini V3.0 & TFT35 E3 V3.0.1 in an Ender 5 plus - although I would have enjoyed just using the stock screen... alas here we are.

I've run down the tips from Radek8 here - bigtreetech/SKR-3#24

• I didn't follow anything from EricH-DW at the bottom because he's using a different set-up. Didn't even want to try to mess with that. I will if that's what is suggested here though.

I've also looked at the amendments made by ThunderClap86 here - bigtreetech/BIGTREETECH-SKR-mini-E3#724

I'll put the changes I've made in my own words to show if I've actually followed this accurately, or if it's just user error on my end.

-Compiled Marlin 2.1.2.5 for my ender 5 plus to send to the SKR Mini
-opened the config.h file in VSCode, changed line 93 to:
#define MOTHERBOARD BOARD_BTT_SKR_MINI_E3_V3_0

-Defined 1st serial_port on line 106 to:
#define SERIAL_PORT 2
#define BAUDRATE 115200 (line 119)

Defined 2nd serial_port on line 128 to:
#define SERIAL_PORT_2 -1
#define BAUDRATE_2 115200

And 3rd serial_port to:
#define SERIAL_PORT_3 3
#define BAUDRATE_3 115200

In the Platfolioini.io I have:
default_envs = STM32G0B1RE_btt

I have the config.ini file changes for the TFT display as follows:
Line 101 - serial_port:P1:6 P2:6 P3:6 P4:0

Along with these changes I have swapped the RT and TX wires from the RS232 port to the UART3 port. TX wire in on the left pin on the UART3 port and the RT wire is on the center pin in the UART3 port.

I've checked the baudrates and ports in the settings on the display itself. Here are the readings:
1 - Printer - 115200
2 - Wifi - 115200
3 - UART3 - 115200
4 - UART4 - OFF

I've made these changes and I'm still getting the same "No printer attached" message.

What am I doing wrong?

[rondlh]

See picture below, there is a 5 pin header marked "TFT" (just below and to the right of the micro controller).
The pinout is given below the board: RST RX2 TX2 GND +5V. These pins are in the correct order for your TFT, so don't cross any wires. It's serial port 2, which you have correctly set to your 1st serial port at 115200 baud. It will be the first serial port on your TFT, "1 - Printer" which you also have correctly setup to 115200 baud. So if you correctly connect the 5 pin header to the TFT, then it should work. If not then check you wire.
If it still doesn't work, then you can try to hook up a serial interface to the board directly, and see if you can talk to it at 115200 baud. You can use Putty or similar software (Arduino IDE also works).