mmu2 Can not connect skr 1.4 turbo

[pstit006]

I have tried and tried I cannot get the mmu2 dip to communicate with the skr 1.4 turbo any and all help would be appreciated I'm running marlin 2.0.7.2 I've flashed the mmu2 dip to run 3 tmc2209 drivers

[pstit006]

Can anybody help

[XylenC4]

I've got it working. Configuration_adv.txt Configuration.txt

I'm using the TFT Socket so SERIAL0. To use this port it has to be disabled for general G-Command usage //#define SERIAL_PORT_2 0

last but not least you have to define the Port (Serial is SERIAL0) // #define MMU2_SERIAL_PORT 0

define MMU2_SERIAL Serial

Make sure you're serial connection is right!

[pstit006]

Ok I will give that a try I'm running a tft70 and I watched a video for using the i2c serial as serial 3 so I could keep my tft

[XylenC4]

If you only use MARLIN Mode on the TFT (as I do) it will work without Serial0

[pstit006]

Ok I've been trying to get this board to work I'm using the btt mmu2-dip board with tmc2209 drivers I've tried connecting to the tft port and still not talking to the mmu2-dip

[AJAX2500]

Hey guys. I spent a lot of time smashing my head against a wall on trying to get the MMU board to connect to any board running 2.0.7.2 and ultimately I found that in the version.h of the MMU firmware file there is the following line.

static const uint16_t fw_buildnr = 130; //!< number of commits preceeding current HEAD

Once I changed this to the following everything connected up and worked perfect.

static const uint16_t fw_buildnr = 132; //!< number of commits preceeding current HEAD

Hope this is helpful to you!

[Ven827]

Hey, just having a similar issue, my serial port seems to be 3.3V while the MMU2 needs 5V, I plugged it into a different 5V source and it works but I wasn't able to get any communication to happen. I'm also not able to compile if I comment out #define MMU2_SERIAL_PORT 0. Any help would be appreciated.

[XylenC4]

I'll haven't compiled Marlin for a while as I'll moved over to a SKR PICO and KLIPPER and a Palette 2+ so take my answer with a grain of salt...

You shouldn't comment it out but replace the #define MMU2_SERIAL_PORT 0 with #define MMU2_SERIAL Serial. The MMU will require a serial port for communication, so there is no sense on disabling the port by removing the line.

Use a USB -> Serial Port adapter to verify the TTL (5V) serial communication to the MMU and the communication to your main board (which one do you use).