Rumba and Auto-Bed level

[sniffle]

as to what pin to use, i don't know,

IF pin 6(pwm_2) is used by something else, what is using it? if it isn't shared by anything potentially important you might still be able to use it you might not...

you also have pwm_1 which is pin5, I don't know if the servo need 5 or 12 volts though, i think 5... which means you might have to get creative with connectors if 5v is needed by the servo.

as to the firmware i suggest watching the youtube videos by zennmasterM for setting up ABL, they are as close to a step by step guide you can get, for software and procedure to get offesets etc setup correctly.

As to when you home all axis or home Z it will raise the z axis extend the probe and then lower Z until it hits the endstop

[tsteever]

I have studies those vids to a point where I think I mutter them in my sleep! Very good info there. The trouble, as you pointed out, is I am using a Rumba and breaking ground. It appears this has been done successfully and I am putting piece together from various threads that will help me complete the picture.

The first task right now is to get into the firmware and modify it to use the Servo connected to the either pin5 or 6.

I found this chunk of code and it looks like the code Rumba needs in the pins.h file to enable the servo for ABL use. The trouble I run into as I am learning how to read the code is that I don't follow exactly what is going on in this code. I know I need to use either pin 5 or 6 on the Exp3 port but I don't see this called out below. Unless the code actually calls this pin something else. I bolded the part in the code below that I suspect tells the rumba to use pin 5 on the expo port. Can someone confirm my suspicion? Is there a list somewhere that shows what the firmware assigns each pinout?

//Added to pins.h to control the extra servo at section "Motherboard is 80" (RUMBA).
#ifdef NUM_SERVOS
#define SERVO0_PIN 4 // For RUMBA PWM_1 is to be used for the servo it is on Epansion slot 3, pin 5
#define Z_MIN_PIN 33 //For RUMBA pin 33 is used for Z min.
#endif[/i]

If I am reading this code right, it will tell Rumba that for all servo0 commands, output those to pin4, which is physically pin 5 on the exp3 port.

Another benefit for knowing what pins are what is adding some LED lights. There is a line of code in the pins.h file that says...
#defineLED_PIN13
I would like to know what pin 13 is as it would be super cool to add some LEDS lights that turn on while printing as a warning to all bystanders that the bed is HOT! I assume that a simple g code could be added to the custom slicer setting to turn these on or off accordingly. But, I don't want to get too far off the point of this thread.

[sniffle]

You need to research your servo and see what its specs are. According to that code it calls pin 4 for the servo pin which unless im looking at it wrong is a ground... Lemme see if i can look up some things to help.

What servo are you using?

[tsteever]

I am using the Hextronic hxt900 called out in the guides. The pinout is where I am getting confused. I know I need to rewire the jack to get the power and the PWM pins in the write locations, I am not troubled by that.

What troubles me is the assigning of the signal pin in the firmware. The EXP3 pinout shows pwm_1 as being pin 5 but the road calls out servo0 to be on pin4, which then in the comments it says pin 5.

Now, as I understand it, there are digital and analogue pins on these boards and it may be calling out pin 4, which is actually pin5. See why I am confused! I cannot find drawing or document that labels this anywhere.

[sniffle]

Ok to use pin 5 and yes in the firmware it should be a 5 not a 4 as according to the spec sheet you are quoting which came from the reprap wiki is ground. The fun part in All of this is you need a 5v power source and a ground which is all well and good they are right together but pin 5 is on the other side of the rail. So you will need another connector to set that pin up as your servo pwm.

[tsteever]

So the code should look something like this...


//Added to pins.h to control the extra servo at section "Motherboard is 80" (RUMBA).
#ifdef NUM_SERVOS
#define SERVO0_PIN 5 // For RUMBA PWM_1 is to be used for the servo it is on Epansion slot 3, pin 5
#define Z_MIN_PIN 33 //For RUMBA pin 33 is used for Z min.
#endif[/i]

[sniffle]

Sigh it may be sortware pin 4... They dont have a reference for that on the sheet... Which is annoying the rambo spec sheet does...

[sniffle]

I found where you are getting the reference for that code. Yes his code would be correct.

Software pin 4 which is physical pin 5 on the board.

I know confusing... But the software and hardware pin references cant always line up...

[sniffle]

After further reading of that post you CAN use pwm_2... It is logical(software) pin 5...

Pwm_2 is only used if you are using a thermocouple

While using a thermistor pwm2 is not used.

[tsteever]

Which post are you referring to? I am wading through the ABL thread on the riprap forums and must not have gotten that far.

The software vs hardware pins are I think the part I am getting turned around on. When you are just learning these things and there are all these little gotchas, it is confusing. My search for a hardware/software pinout has been fruitless.

Okay, so I understand what you are saying. Since I am not using a thermocouple, this pin is unused. The question is, is it still defined? Should the following be uncommented to look like this?

//#define TEMP_1_PIN 5 // ANALOG NUMBERING - connector *K2* on RUMBA thermocouple ADD ON is used

I found the following code that is different from the code I put in the post above. This code was reportedly added to the pins.h file to get a servo working on the Rumba. The first part, where it defines (software) pin 5 to servo0 is the same. But why the difference in the second part? This was referenced in the same thread on page 8.

#ifdef NUM_SERVOS
#define SERVO0_PIN 5

#if NUM_SERVOS > 1
#define SERVO1_PIN 4
#endif

#endif

In order to put a more complete how-to together, I also need to modify the servo section in the config.h tab to activate the servo for ABL use.

// Number of servos
//
// If you select a configuration below, this will receive a default value and does not need to be set manually
// set it manually if you have more servos than extruders and wish to manually control some
// leaving it undefined or defining as 0 will disable the servo subsystem
// If unsure, leave commented / disabled
//
#define NUM_SERVOS 1 // Servo index starts with 0 for M280 command


// Servo Endstops
//
// This allows for servo actuated endstops, primary usage is for the Z Axis to eliminate calibration or bed height changes.
// Use M206 command to correct for switch height offset to actual nozzle height. Store that setting with M500.
//
#define SERVO_ENDSTOPS {-1, -1, 0} // Servo index for X, Y, Z. Disable with -1
#define SERVO_ENDSTOP_ANGLES {0,0, 0,0, TBD,TBD} // X,Y,Z Axis Extend and Retract angles


Finally, in the videos that Michael (ZenmasterM) posted he listed servo angles for extend and retract. When looking at his setup the probe he is using retracts towards him. The parts I downloaded from Thingiverse has the probe retracting into the extruder, the opposite direction. My guess is my numbers will be flipped compared to his. More like 60, 180.

I know there was a lot in this post but all your input is appreciated.