Help with board connection

LowRider CNC Troubleshooting
1

I’ve completed my LR3 build this evening and am receiving the “no printer attached” error referenced in this thread. I purchased my SKR Pro controller and TFT from V1 in September. Was there ever a root cause or countermeasure ID’d which will allow me to use the GUI? This controller works perfectly in Marlin mode.

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No Printer Attached is the error message that the TFT gives put when its queries on the serial port are not answered in the expected format.

This can stem from several problems.

  1. The black serial connection cable is incorrectly installed. This is a 5 pin cable and must attach to the correct UART on the screen PCB and on the SKR Pro board in the correct places (see docs.) One simplistic and incomplete test is to see if the reset button on the TFT resets the SKR. This is the 5th wire on the black ribbon cable that is separate from the other main 4.

  2. The connection speed is incorrect. This is determined on the TFT side in the config file. It is determined on the SKR Pro in the Marlin configuration.h file. V1 firmware sets this to 250000 baud.

  3. Firmware is incorrect. The V1 firmware enables the TFT serial UART in the Marlin cinfiguration, and the TFT comfiguration file.must also enable that serial communication. Note that Marlin Mode on the TFT does nkt even need this connected in order to work. Also only the matching Marlin firmware will respond in a manner that the TFT will tecognize. For example, RepRap Firmware can be installed on the SKR Pro, but will end up with the “No Printer Attached” error because the reaponse format for the status query is different.

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Thanks , Dan!
With your help, I have a connection now.

Would you happen to know what the V1 Engineering GUI top screen is supposed to look like? My GUI screen and the sub menus look like 3D Printer focused.

IMG_1080
IMG_1080480×640 92 KB

I can’t seem to find any of the V1 LR specific routines I’m accustomed to in the Marlin interface.

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That is it.

The custom button has some things, and you can add to them if you would like.

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OK…thank you Ryan. Great job with LR3.

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