TMC2208 V3 UART on RUMBA Board - Raise3D N2

General Discussion
1

Basic Information:

Printer Model: Raise3D N2
MCU / Printerboard: ATmega2560 / RUMBA (Raise3D)

Bonjour,
After successfully solving my temperature problem, I’m trying to implement TMC2208 V3 Bigtreetech on the X Y axes in UART.

After many hours of research to try to understand what the UART is, I already see much better what I have to do.

Everything is still not very clear, and on how I have to connect the drivers to the motherboard. The setting of the printer.cfg file seems more obvious to me although I do not know the uart_pin:

I am looking to see if I can connect them without putting a wire from the UART pin to EXP3.
I wonder if I can only play with the MS1 MS2 MS3 micro switch. If so what is the right combination?

I put here some documents that may be useful:

Schematic RUMBA

Old conversation about setting up this type of driver.

Other people seem to have used SD2224 in UART

BIGTREETECH TMC2130 V3.0 , TMC2208 V3.0 ,The strongest TMC2208

RUMBA Tutorials

Conversation on UART

2

If you want to be able to control the drivers via software then this is needed

No

1 Like
3

OK, thanks for the info.
So what does it do besides setting the vref by code?

4
  • Read status messages, like errors etc
  • Set run_current
  • Switch between stealth chop and spread cycle
  • Set microstepping
5

That’s a big one, when adjusting the stepper motor driver current where there wasn’t a UART connection, I used to use one hand to hold the screwdriver to adjust the pot and my other two hands to hold the DVM leads.

6

Thank you both, you have fully convinced me.
I think I will spend more time on it because I was starting to have a good technique with the multimeter and the screwdriver, but indeed it will be easier to be able to set up everything by command line.

I will also be able to use the Pressure advance when we have the UART communication?

7

This is independent.

My personal opinion: Spend 30 USD and get some “BTT SKR something” or “MKS something” or “FYSETC something” entry level board and kick out the RUMBA board

8

Yes, I understand, of course I thought about it, but it’s also a lot of wiring work.
They sold quite a few machines, I was hoping to provide quite a few users with a little upgrade.

Now I’m trying to figure out how to wire and what to put in my code.

Wiring:
To communicate in UART, I understand that you need an RX and TX.
All explanations of connection of UART drivers have only one cable
Capture d’écran 2023-02-19 à 10.36.46

Looking at the Raise forum, some people have enabled the UART by connecting PJ0 and PJ1. Can you confirm me that the wiring is good? Unfortunately, I didn’t understand where to connect for Z and E (but that’s less important)

Capture d’écran 2023-02-19 à 10.43.46
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Capture d’écran 2023-02-19 à 10.29.28
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Concerning the code, I have a vague idea, but it’s not super clear yet.

[tmc2208 stepper_x]
uart_pin: P?
microsteps: 16
interpolate: True or false?
hold_current: 0.5 or more?
run_current: 0.7 or more?
stealthchop_threshold: 600 or more?
I don’t think I need this and I don’t even know what that means
driver_PWM_AUTOGRAD: True or false?
driver_PWM_AUTOSCALE: True or false?
driver_HEND: 3
driver_HSTRT: 0

[stepper_x]
step_pin: PH0
dir_pin: PH1
enable_pin: !PL1
microsteps: 16
rotation_distance: 40
endstop_pin: ^!PC0
#endstop_pin: ^PC1
position_endstop: -10
position_min: -10
position_max: 300
homing_speed: 50

9

See, this is exactly what I meant: It usually ends up in a holy mess to sort it out.
Some general remarks:

10

I do need the machine quickly.
I will surely follow your advice and change the card but later.

I finally unsoldered the resistor of the TMC2208 V3 drivers from UART mode to put them in STEP/DIR.
I set the Vref to 0.9V like on the TMC2100 (Stock).

J’ai changé

rotation_distance: 40
to
rotation_distance: 80