Hey there,

I am currently thinking of replacing my MKS Gen L with an SKR1.3 Board.
Since I have a bigger CoreXY (300x300x350) machine and may want to use some higher print speeds I guess 32 bit is the way to go.

Good thing is MKS Gen L and SKR 1.3 are the same fomat thus I can use the same mounting etc.

Bad thing is I think the SKR 1.3 has less usable I/O Pins so I may have to scrap the filament runout sensor.
Do you guys see a possibility to keep it?

My current layout is as follows:
I need (additional) digital pins for
- Two extruders/hotends with each its own auto-cooling-fan
- BLTouch
- StatusLED (Neopixel only uses one D pin)
- Filament runout sensor
- 10 TX/RX pins for TMC2208 UART


Subtracting the TX/RX pins since they are already hardwired on the board I need 5 I/O pins for the additional features.
Lets now have a look at the SKR1.3

It looks like I am short on one pin (which I decided to be the filament runout sensor then)

But I don't have any experience with the SKR1.3 Board or the 32 bit boards and Marlin 2.0 in general so if you guys see a possibility to keep the filament runout sensor on the SKR1.3 please let me know

That was one reason I decided to go with a Re-ARM/RAMPS solution instead of the SKR 1.3 when I upgraded my machine to 32 bit. In my case it was the lack of a PS_ON pin plus available pins to run RGBW LEDs. I like the fact that the SKR 1.3 handles TMC drivers without extra wiring, but unfortunately the lack of GPIO pins is a problem in my use case.

Quote
MMcLure
That was one reason I decided to go with a Re-ARM/RAMPS solution instead of the SKR 1.3 when I upgraded my machine to 32 bit. In my case it was the lack of a PS_ON pin plus available pins to run RGBW LEDs. I like the fact that the SKR 1.3 handles TMC drivers without extra wiring, but unfortunately the lack of GPIO pins is a problem in my use case.

But wait, I think you should be able to manage the PS_ON pin in pins with Marlin, no? Or does it need to be a physical PS_ON pin that is impossible to set to a specific pinout?

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http://www.marinusdebeer.nl/

By the way I was wondering whether you could connect TMC2208 UART the "complicated" way to the SKR.

I know on the SKR there are Jumpers for using UART which you can set if you have all the pins facing downward on the TMC2208.
But since I used mine on the MKS Gen L before I have two pins soldered facing upwards to connect a RX and TX wire (the latter with the 1K Resistor) to it like this

Can I just connect the TX and RX ends to the jumper pins to use UART too?
I obviously have no clue how the board handles the internal wiring for UART

You might be able to connect the pins directly to the board but I am also doubting where.

I think it would be safest to just reverse the pins to the bottom of the board again. I don't see any pins labeled Rx or Tx on the board on any side:
[github.com]

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http://www.marinusdebeer.nl/

Quote
Ohmarinus
I don't see any pins labeled Rx or Tx on the board on any side:
[github.com]

I am not sure either but in reference to the SKR1.3 pinout from above (my first post) there are pins stated for UART (top middle) I guessed they could be the ones below every driver...
Like this:


But in that case it could be that the 1K Resistor is already connected to the TX pin... this would not help me since I would have another Resistor then in line with the wire...

Edited 1 time(s). Last edit at 06/25/2019 08:49AM by Schild0r.

Quote
Ohmarinus

Quote
MMcLure
That was one reason I decided to go with a Re-ARM/RAMPS solution instead of the SKR 1.3 when I upgraded my machine to 32 bit. In my case it was the lack of a PS_ON pin plus available pins to run RGBW LEDs. I like the fact that the SKR 1.3 handles TMC drivers without extra wiring, but unfortunately the lack of GPIO pins is a problem in my use case.

But wait, I think you should be able to manage the PS_ON pin in pins with Marlin, no? Or does it need to be a physical PS_ON pin that is impossible to set to a specific pinout?

Setting the PS_ON pin to a generic GPIO pin is not a big deal - just a tweak to the pins.h file for the board. However pretty much all of the pins that are available as GPIO on for example a RAMPS are directed to the stepper driver jumpers on the SKR. Which makes them really easy to use for driving TMC steppers but makes them a real pain to use as GPIO if you're using "dumb" steppers. I just wish they'd added a GPIO pin header for those of us still using dumb steppers. All of the easily available GPIO pins on the EXP1/EXP2 connectors are taken up by an LCD.

Quote
MMcLure

Quote
Ohmarinus

Quote
MMcLure
That was one reason I decided to go with a Re-ARM/RAMPS solution instead of the SKR 1.3 when I upgraded my machine to 32 bit. In my case it was the lack of a PS_ON pin plus available pins to run RGBW LEDs. I like the fact that the SKR 1.3 handles TMC drivers without extra wiring, but unfortunately the lack of GPIO pins is a problem in my use case.

But wait, I think you should be able to manage the PS_ON pin in pins with Marlin, no? Or does it need to be a physical PS_ON pin that is impossible to set to a specific pinout?

Setting the PS_ON pin to a generic GPIO pin is not a big deal - just a tweak to the pins.h file for the board. However pretty much all of the pins that are available as GPIO on for example a RAMPS are directed to the stepper driver jumpers on the SKR. Which makes them really easy to use for driving TMC steppers but makes them a real pain to use as GPIO if you're using "dumb" steppers. I just wish they'd added a GPIO pin header for those of us still using dumb steppers. All of the easily available GPIO pins on the EXP1/EXP2 connectors are taken up by an LCD.

Ahhh, so if you're using only E0 it might be possible to remap the pins from E1 to do the PS_ON?

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http://www.marinusdebeer.nl/

Quote
Ohmarinus
Ahhh, so if you're using only E0 it might be possible to remap the pins from E1 to do the PS_ON?

That would probably work.

I had a filament run-out sensor on my printer that had a smoothieboard. I believe it can be set up to pause the print and resume when filament is loaded, but I didn't do that because the printer was at the makerspace (using it would be too complicated), so I just had it stop the print and shut off the heaters.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Hi,

Maybe a little late, but...

Have you considered adding a TFT screeen to your MKS1.3? These ones have a few I/O expansions, useful for filament runout sensor, etc:

Bigtreetech TFT35 V2.0 Touch Screen Smart Display for SKR 1.3

You may have to give up on your existing LCD, I haven't been able to have both working at the same time (haven't spent much time on it anyway).

Just an idea for future reference,

Joaoabs

You could possibly use the Max end stops.