Mainboard - Select Mini V1 & V2 - New "Quiet" Version

Compatible with:

• MP Select Mini V1
• MP Select Mini V2
  

Please be sure to pay extra attention to the first "IMPORTANT NOTE" listed below. The rest should be read also but the first note contains useful information.

Includes:

• Heat sink (will be preinstalled). The product images do not show a heat sink installed but that was only to show off the TMC2208 steppers drivers.
• Three (3) 2 to 3 pin endstop adapters. The endstop plugs for the Select Mini V1 and V2 are 2-pin. The adapter makes it so those plugs can plug into the 3-pin header on the mainboard.
• Two (2) fan adapters. The Select Mini V1 hotend fan uses a slightly larger plug than the V2. The adapter is to convert from the larger size to the smaller size that is on the mainboard. 
• One (1) 4 pin cable for the display. The Select Mini V1 and V2 use the same plug size on the side that connects to the display/UI board but the plug on the mainboard side is slightly larger on the V1. The included 4 pin cable is only needed if the printer is a V1. The cable will work with both the V1 and V2 but if your existing V2 cable is working then there is no need to swap. (The included display cable is a little longer than the original on purpose. The idea is that it will allow for the bottom plate to lay flat on the work surface while the printer is on its back.)

IMPORTANT NOTES:

1. The customer will not need to provide any stepper motor information after purchasing this version of the mainboard as they had to with the other "Quiet" versions. If you believe you have a V2 or if you find that any of the motors are running hot then you may want to reduce the stepper driver current. This can easily be done using the gcode M907 command. The X and Y axis and the extruder can have the current output set using the digital trimpots (X and Y are both tied to X for setting the current meaning they cannot have different current output values). The current output for the Z-axis is not adjustable but both the V1 and V2 use the same exact Z-axis motor. The current output for the Z-axis is enough that it should have no problems with using a Nema 17 stepper motor with 8mm leadscrew.
   If you are unsure which stepper motors your printer has please feel free to contact GigDigit with either a picture of the X,Y, or E stepper motors model number or just the model number for one of the three motors.
• The examples below are for boards with 0.33 Ω sense resistors for X/Y and 0.24 Ω sense resistors for E.
  (This information may be slightly modified when you receive your order. If there is a change the updated information will be included with your board.)
• Example:
  M907 E500 ; set max current to ~950 mA for the extruder (Vref = 1.97 V)
  M500 ; save the new value to memory
• V1's (should have 2 ohm stepper motors)
• Try these settings if you have a V1: (Adjust as needed)
  M907 X530 ; set max current to ~800 mA for the X and Y axes (Vref = 2.21 V)
  M907 E525 ; set max current to ~1.03 A for the extruder (Vref = 2.15 V)
  M500 ; save the new value(s) to memory
• V2's with 10 ohm stepper motors (please contact GigDigit if you are unsure)
• Try these settings if you believe you have a V2 with 10 ohm motors or if a motor is running hot: (Adjust as needed)
  M907 X450 ; set max current to ~540 mA for the X and Y axes (Vref = 1.51 V)
  M907 E425 ; set max current to ~620 mA for the extruder (Vref = 1.29 V)
  M500 ; save the new value(s) to memory
• V2's with 2 ohm stepper motors (please contact GigDigit if you are unsure)
• Try these settings if you believe you have a V2 with 2 ohm motors: (Adjust as needed)
  M907 X530 ; set max current to ~800 mA for the X and Y axes (Vref = 2.21 V)
  M907 E425 ; set max current to ~1.03 A for the extruder (Vref = 2.15 V)
  M500 ; save the new value(s) to memory
• Firmware defaults are:
• M907 X400 E425
  X/Y: ~410mA (Imax) [Vref = 1.14 V]
  Extruder: ~620 mA  (Imax) [Vref = 1.29 V]
  Z: ~640 mA (Imax) [Not adjustable]
2. This mainboard does not use the same firmware as the stock V1 or V2 firmware. It uses a different MCU than the stock mainboards. The firmware installed on the mainboard will be the most up to date version at the time it ships to you.
3. This mainboard will work with both the Select Mini V1 and Select Mini V2. At this time, the Select Mini Pro/V3 is not supported but hopefully will be added. (The reason it will not work with the V3 is because the firmware is lacking support for the inductive sensor. If you are buying for a Pro/V3 because you are not using the inductive sensor then please use the Contact Us page prior to purchasing to request that the mainboard has the ribbon cable connector for the bed heater installed.)
4. The firmware currently does not support folders on the microSD card. This means no folders can exist on the microSD card. The printer will see the folders, but it will not be able to select a file to print if any folders exist on the card.
5. This board has an upgraded MCU (processor) and the firmware has better microSD card support than the original mainboards. Some 32GB and higher cards that have been tried did work but not all. All 16GB and less microSD cards that have been tested with this board have worked but of course that does not mean that every 16GB card will work.
6. The current version of the firmware does not have any limitations on the bed heater like what exist on the original Select Mini V2 mainboards/firmware. If possible, it would be better to use a 12V 10A power supply. The V2 stock power supplies are 12V 7A but seem to have no problem periodically exceeding 7A without shutting down. There is currently not a build of the firmware that has the bed heater restriction/limits in place but if enough requests are received then maybe a build can be made available.
7. The current firmware does not include support for PID tuning for the bed heater.
8. The current firmware does not include support for being able to use a 104GT-2 type thermistor. The current firmware only supports the same type of thermistor (NTC 3950 K) as the stock printer. 

The text below is from the previous "Quiet" mainboard product description but most/all applies to the new version with the exception of being able to add variable resistors upon request because there is no need to do this via hardware since the firmware supports adjusting the max motor current with the M907 gcode command.

Here is a Google Photos album with videos and a couple pictures that show off the TMC stepper drivers. Some pictures show variable resistors which will not be on the mainboards because they are not needed but can be added for an additional cost if they are wanted.

Basically, it will make the printer much quieter when printing. There fans will be the loudest part of the machine and then maybe a little bearing noise but that will vary from printer to printer.

I will not claim that swapping the stock A4988 stepper drivers with TMC2208 stepper drivers will make prints come out better or print faster. I will say that this upgrade will make the printer much quieter without loss of quality or speed. No firmware modifications are needed. No hardware changes must be made by the user to accommodate the upgraded stepper drivers. However, for the Select Mini V1, adding a fan to the base of the printer to move air across the mainboard (specifically the stepper driver heatsink) would be a good idea especially if the printer is used in a room that is fairly warm. As far as the user is concerned all is the same regarding hooking up the board and printing with the same slicer settings as used before.

NOTE: The TMC2208 drivers are running in "legacy mode". The TMC2208 will interpolate received step signals to 256 micro-steps. UART is not available in legacy mode.