So the “No Printer Attached” is driving me nuts.
- Tried V1 TFT FW, with Marlin config, no luck
- Tried V1 TFT FW, with RRF config, no luck
- Recompiled the TFT35 E3 V3 to use another serial port (3) instead of default: no luck
(used these topics for pointers 1 & 2) - Changed baudrate 57,6K ~ 250K, no luck
- Changed baudrate protocol, no luck
The only thing it does is homing & moving after homing.
The board.txt contains:
// Board Hardware configuration file for SKR Pro
// generated by RepRapFirmware Configuration Tool (LPC Version) v3.4.0-LPC-STM32+6
// on Fri Apr 07 2023 12:00:45 GMT+0200 (Midden-Europese zomertijd)
//Note: Each line should be less than 120 characters.
// : Unwanted options can be commented out or set to NoPin. Lines commented out will get default values
// : for pins the default is NoPin.
// : Values for Arrays need to be contained within { and }
// : Comments can be defined with // or # (comments are not supported inside arrays)
// : Each config entry must be all on a single line.
board = biquskrpro_1.1;
//LED blinks to indicate Platform is spinning or other diagnostic
//Comment out or set to NoPin if not wanted.
leds.diagnostic = A.7;
heat.tempSensePins = {}; //Max of 3 entries
//heat.spiTempSensorCSPins = { }; //Max of 2 entries
//TMC Smart Drivers
stepper.numSmartDrivers = 5;
//Connecting a screen to a SKR Pro v1.1 and v1.2
//https://teamgloomy.github.io/skr_pro_screen.html
serial.aux.rxTxPins = { PA_10, PA_9 }
The config.g contains (I added your tool to check this is not the problem):
; Configuration file for SKR Pro (firmware version 3)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool v3.4.0-LPC-STM32+6 on Fri Apr 07 2023 12:00:45 GMT+0200 (Midden-Europese zomertijd)
; General preferences
G90 ; send absolute coordinates...
M83 ; ...but relative extruder moves
M550 P"CNC_LR3" ; set printer name
; Network
M552 S0 ; disable network
; Drives
M569 P0 S1 ; physical drive 0 goes forwards using default driver timings
M569 P1 S0 ; physical drive 1 goes backwards using TMC2209 driver timings
M569 P2 S1 ; physical drive 2 goes forwards using default driver timings
M569 P3 S1 ; physical drive 3 goes forwards using default driver timings
M569 P4 S0 ; physical drive 4 goes backwards using TMC2209 driver timings
M584 X0 Y1:3 Z2:4 ; set drive mapping // MODIFIED X on drive 0, Y on 1 and 3, Z on 2 and 4
M350 X16 Y16 Z16 E16:16 I1 ; configure microstepping with interpolation
M92 X80.00 Y80.00 Z400.00 E80.00:80.00 ; set steps per mm
M566 X900.00 Y900.00 Z60.00 E900.00:900.00 ; set maximum instantaneous speed changes (mm/min)
M203 X3000.00 Y3000.00 Z900.00 E3000.00:3000.00 ; set maximum speeds (mm/min)
M201 X180.00 Y180.00 Z80.00 E180.00:180.00 ; set accelerations (mm/s^2)
M906 X900 Y900 Z900 E900:900 I30 ; set motor currents (mA) and motor idle factor in per cent
M84 S60 ; Set idle timeout
; Axis Limits
M208 X0 Y0 Z0 S1 ; set axis minima
M208 X646 Y2092 Z129 S0 ; set axis maxima
; Endstops
M574 X1 S1 P"^xstop" ; configure switch-type (e.g. microswitch) endstop for low end on X via pin xstop
M574 Y1 S1 P"^ystop+^e1stop" ; configure switch-type (e.g. microswitch) endstop for low end on Y via pin ystop & e1stop
;M574 Z2 S1 P"^zstop+^e0stop" ; configure switch-type (e.g. microswitch) endstop for high end on Z via pin zstop
M574 Z2 S1 P"^e2stop+^e0stop" ; configure switch-type (e.g. microswitch) endstop for high end on Z via pin e2stop & e0stop
; Z-Probe
M558 P5 C"!^zstop" H5 F120 T600 ; set Z probe type to switch and the dive height + speeds
M558 H30 ; *** Remove this line after delta calibration has been done and new delta parameters have been saved
G31 P500 X0 Y0 Z14 ; set Z probe trigger value, offset and trigger height
M557 X100:600 Y150:2000 S100 ; define mesh grid
; Heaters
M140 H-1 ; disable heated bed (overrides default heater mapping)
; Fans
M950 F0 C"fan0" Q500 ; create fan 0 on pin fan0 and set its frequency
M106 P0 S1 H-1 ; set fan 0 value. Thermostatic control is turned off
M950 F1 C"fan2" Q500 ; create fan 1 on pin fan2 and set its frequency
M106 P1 S1 H-1 ; set fan 1 value. Thermostatic control is turned off
; Tools
M950 R0 C"!exp.heater2" L10000 ; Create spindle index 0, with PWM pin on heater 1 and 10000 RPM achieved at full PWM
M950 R1 C"!exp.heater1" L10000 ; Create spindle index 1, with PWM pin on heater 1 and 10000 RPM achieved at full PWM
M563 P0 R0 S"Makita RT0701C" ; Create tool 1 with spindle 0 and call it "Spindle 1"
M563 P1 R1 S"NEJE A40640" ; Set tool 1 to be the laser
; TFT
;M575 P1 S2 B250000 ; Set TFT serial port & baudrate to TFT settings
M575 P1 S2 B57600 ; Alternative
;M575 P1 S0 B115200 ; Alternative
; https://teamgloomy.github.io/skr_pro_screen.html
; Custom settings
M453 ; set to CNC mode
; https://docs.duet3d.com/User_manual/Reference/Gcodes#m453-select-cnc-device-mode
sorry, I do not have a serail FTI, it is been years that I´ve been hacking hardware 
But I am confident that the UART wont be the problem.
As I remapped the UART on TFT to UART 3 without succes.
Could you maybe share your RRF confi.ini for the board? Could try that as last resort as I am out of idea´s