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Aux4 on RAMPS board

Discussion in 'Mods and Upgrades' started by Bd182, Mar 11, 2019.

  1. Bd182

    Bd182 Member

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    I wish to implement some add-ons. I've added a cable to the first four pins of the Aux4 connector of the RAMPS board, but pin 1 does not appear to have 5 volts and so I am suspicious of the Ground, D32, D47, etc.

    Does anyone know if our Aux4 does not match the Aux4 of the standard RepRap RAMPS?
     
  2. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
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    I'd guess it doesn't BUT I don't have an R1+ RAMPS board handy -- I do have one R1+ stored, but I am not at a point where I am willing to get to it and disassemble it :)

    They disabled a lot of the extra connections on their custom RAMPS and honestly -- as cheap as a standard RAMPS 1.4 IS you would be better served just switching over to using one if you want to do more customization. There is a thread that @Geof wrote up that shows you have to do that swap.
     
  3. Bd182

    Bd182 Member

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    Crap. This was supposed to be easy. I suppose we don't have access to a circuit diagram of the R1+ RAMP layout?
     
  4. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
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    No, they did not document it at all.
    Allegedly -- it was electrically the same, but with missing/rearranged connectors and pinouts for stuff that they did not need/use on their printer (probably a cost savings long-term, but that is a wild assed guess)

    Given the cost of a standard RAMPS 1.4 in bulk I am not feelin' the savings :)
     
  5. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
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  6. Bd182

    Bd182 Member

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    Doesn't make sense. There is a header for Aux4. It wouldn't save any money to leave out the traces that connected it. It would have saved money to leave off the header completely. Maybe something else is going on I don't understand yet.

    I'm worried about a standard RAMPS board. They're all cheap Chinese crap with warnings about fire and poor construction. I'd pay $50 to get a good American made board.
     
  7. Geof

    Geof Volunteer Moderator
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    hate to be that guy, but even the board from Robo is a "cheap chinese crap" board lol. Thats why we all recommend the all in one kits from amazon. If you want genuine real deal you can buy directly from Arduino for the mega/ramps
     
  8. Bd182

    Bd182 Member

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    But I imagine Robo has vetted their board to get a good one. Buying Chinese on Amazon or eBay is a crap shoot.

    I'm still thinking there must be real signals on Aux1 and Aux4. If anyone had an unplugged RAMPS board to look at the bottom side, it would be handy....
     
  9. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
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    If by "good one" you mean "works on arrival", yes :) I agree (bear in mind theirs are from China too). Other than that I would not presume too much in terms of quality ...

    It can be a crap shoot to buy individual, $12-ish, boards from China via Amazon -- I agree (and that is why i usually only buy the full kits will all of the electronics, my track record with those having working boards is 100%). Risk you run. Granted if you buy via a Prime listing they will make it right, but then you hassle with swapping it out. Last time I opted for individual RAMPS boards I bought 4 from different vendors (all Prime) and got one that worked -- Your Mileage May Vary. :)
     
  10. Bd182

    Bd182 Member

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    So the full kits are more reliable? Why would that be?

    Looking at my bare Arduino Mega, I see that the bottom header (Aux4) does NOT have 5 volts at pin 1, it's on the other end. Since I don't measure 5 volts, I'm wondering why the RepRap RAMPS 1.4 board shows 5 volts there. Maybe the document I got off the web is wrong. Guess I'll be opening the Robo back up...

    The more repairs I have to make to the Robo, the more familiar I become with the hardware, and the more I understand how it's just an assembly of off the shelf parts that are easy and cheap to buy. Thinking about building my own with 2020 extrusions. Doesn't seem that hard to do.
     
  11. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
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    As a wild guess? Because they test them.

    Whoomp! Der it is :)
    You nailed it. It is cheap and easy to maintain and repair.
     
  12. Bd182

    Bd182 Member

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    Plus, you could make one that was, say, 24" long and 4" wide if you wanted. Or tiny and fast. Why, the possibilities are endless.

    Jason at Robo forwarded me a diagram of the RAMPS 1.4 board and told me the Robo board was the same for aux ports. So I went back to my voltmeter and measured again. I *AM* getting 5 volts at pin 1. There must have been solder flux on the wire end I was measuring originally, preventing a valid reading.

    So, back to my plan to switch off the Robo at the end of a print, pin 3 of Aux4 is labeled as D32. I assumed the code to turn this pin on after a print is to add "M42 P32 S255;" But that doesn't seem to work.

    Anyone else using M42 to address port pins?
     
  13. WheresWaldo

    WheresWaldo Volunteer ( ͠° ͟ʖ ͡°)
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    Are you still using the original Robo firmware?

    Pin32 may not be defined in the pins.h file. I haven't looked at Robo firmware in so long, that's all I got for you.
     
  14. Bd182

    Bd182 Member

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    I am using the Robo firmware. I have looked in pins.h, but it's no help to me, because it contains definitions for a great many motherboards and I have no idea which definitions are used by my R1+. Maybe it's Motherboard 77. Anyway, the pins.h file only seems to assign names to pin numbers. I am imagining that M42 does not require pre-named assignments, but allows direct access to pin numbers of the Arduino. Maybe that's wrong.

    Any idea where I can get more information on using M42?

    M42: Set pin state
    [P<int>] A digital pin number (even for analog pins) to write to. (LED_PIN if omitted)
    S<int> The state to set. PWM-able pins may be set from 0-255.
     
  15. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
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    CONFIGURATION.H tells you the motherboard type:

    #define MOTHERBOARD 33
     
  16. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
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    Pin.h DOES assign variable names that Marlin uses internally for each pin the motherboard supports, but if the pin is NOT defined it is assumed to be unsupported.
     
  17. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
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    Be careful because some of the pins are used in certain situations and may be paralleled to other pins on the I/O ports.

    #define BTN_ENC 32

    for example is used as part of the LCD driver routines (maybe you do not have an LCD installed -- not a problem then). It MAY not be a problem with an LCD -- I'd have to dig through it more to see which type of LCD wants that I/O pin :)
     
  18. Bd182

    Bd182 Member

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    I had narrowed in on motherboard 33. It seems many other people have asked the Marlin wizards why M42 does not work for them, and no one has reported success.

    In the Robo community, do people add custom gizmos some other way? Like using an M command to turn on a fan or heater we don't have, and utilize that output?
     
  19. Bd182

    Bd182 Member

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    I printed a bracket to hold a microswitch to the smooth rod of my Z axis. At the end of each print I can program a rise to kiss the switch and shut down the AC with a smart outlet.

    Z limit-b.jpg
     
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  20. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
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    I added a servo to a RAMPS/Arduino that we use to drive our DLP (I think I have a project thread on that if you care).
    So for that I use a custom Mxxx command to open/close the servo which in turn opens and closes a shutter for the projector to control light from the projector curing the resin. Works really well. The slicer then adds those commands (open shutter initially, close shutter -- move Z axis -- switch pictures -- open shutter) to control the print.

    I had a lot more options since the RAMPS has -- one stepper :) For the Z
    and then all it needed to do was control a servo for the shutter.
     

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