Y_MIN is probably the endstop, which isn't on the driver connector, so doesn't need to be changed.by rebecca.palmer - RAMPS Electronics
The difference between Android accessory and normal USB device is which end takes the role of USB host, and as the Mega ADK uses a separate USB chip over SPI to do this, it probably doesn't cause significant CPU load; however, the firmware would need to be changed to read from this interface instead of the normal USB interface. As an easier alternative, the Android OS does also support normal USby rebecca.palmer - RAMPS Electronics
5 wire steppers are unipolar only, and hence incompatible with normal RepRap electronics; this type also doesn't have enough torque. 4, 6 or 8 wire steppers are all suitable.by rebecca.palmer - Stepper Motors, Servo Motors, DC Motors
Try inverting the endstops (change {X,Y,Z}_ENDSTOPS_INVERTING in Configuration.h, then recompile and reload).by rebecca.palmer - Firmware - mainstream and related support
Check continuity of the Y_DIR trace from processor to stepper driver. If it's not that, check whether the voltage on Y_DIR changes when you try to change direction; if it doesn't (and given that you've already tried using different firmware), that processor pin may be faulty, so try using a different one (cut trace, connect with wire to one of the spare pins, change firmware Y_DIR_PIN setting toby rebecca.palmer - Firmware - mainstream and related support
Short across the thermistor connector, or open-circuit pullup resistor (R9/R10).by rebecca.palmer - Sanguino(lolu)
Did you do enable_y() , disable_y() in Marlin.h? Also check that EXTRUDERS is set to 1, to stop the normal 2-extruder code trying to use E1.by rebecca.palmer - Firmware - mainstream and related support
3D-ME Wrote: ------------------------------------------------------- > I have another quick question: I have a 6.8 ohm 3w > heater resistor for my hotend, but it seems to be > a little under-powered for my hot end design, so > I'm wondering, will a 12v 40w ceramic heater > cartridge provide more heat? It will, but requires precautions against fire, as if it becomes stuck on it wilby rebecca.palmer - RAMPS Electronics
What did you change? Check that the baud rate is the same in the serial monitor window and in your code. If you changed the text sent, note that there is a bug that may hang the IDE if too much text is received without any newlines.by rebecca.palmer - Next Wave Electronics Working Group
High reading can be a short to ground (C5, since you've already eliminated the thermistor itself), an open circuit to 5V (R7), or a damaged input on the ATmega. You can tell Marlin to use the spare (T2) thermistor socket by changing TEMP_0_PIN to 15 in the RAMPS section of pins.h and recompiling.by rebecca.palmer - RAMPS Electronics
The "rated voltage" of a stepper is just the voltage that gives the rated current when applied continuously, and can be ignored when using a current-limiting driver (which Polulus are); you just need to set the current low enough (note that you should not use full rated current on a RepRap, to avoid melting the brackets). The 24V-boost option suggests that the Azteeg X3 has the ability to use aby rebecca.palmer - RAMPS Electronics
You don't need a hardware programmer to reprogram the 8U2/16U2: they have a bootloader. (It's also possible to use the second Arduino as a programmer, but note that the connection diagrams there are for reprogramming the main microcontroller, not the U2.) However, I don't know if the firmware is compatible across hardware versions.by rebecca.palmer - Controllers
This issue has come up before with the TB6560 driver (Gen7T/Sanguish); discussions there suggest trying Teacup or possibly Marlin.by rebecca.palmer - Firmware - mainstream and related support
Styler Wrote: ------------------------------------------------------- > Can you detect back > EMF / motor current for single (non-continuous > rotation) microsteps? I'm struggling with a > problem with torque input deflecting the stepper > shaft away from its unloaded position No: the feedback signal is speed*{cos,sin}(position), so at low speed it becomes undetectable and one hasby rebecca.palmer - Controllers
> so I am just > going to go ahead and plug in a RAMPS to my Due. Don't do that with a stock (5V) RAMPS: it may damage the (3.3V) Due (by overvoltage at input pins) and/or the heater MOSFETs (by turning them only partly on so they overheat). However, I agree that designing a modified RAMPS to work with the Due is a good idea.by rebecca.palmer - Firmware - experimental, borrowed, and future
Previous discussions. Summary: it almost certainly can be done, but will require hardware changes because the Due is 3.3V not 5V.by rebecca.palmer - Next Wave Electronics Working Group
Power dissipated in resistor (must be less than rating)=(I^2)*R, voltage across resistor (must be <0.5V for the A3982, see the "Internal PWM Current Control" datasheet section)=I*R.by rebecca.palmer - Controllers
len24 Wrote: ------------------------------------------------------- > Can it be done without programmer? Yes if the processor already has a bootloader on it (as in a Gen7 kit), no if it's completely blank (as bought from a general electronics supplier). Instructions for both methods are here.by rebecca.palmer - Firmware - experimental, borrowed, and future
QuoteTraumflugQuotejbernardisBear in mind, you can't power things like fans, heaters, or even a bank of LEDs directly from the Arduino. An ATmega pin can sink 20 mA, which is sufficient for standard signal LEDs. One LED, not a bank of them, and don't forget the series resistor. QuotenopheadAren't analogue pins numbered independently of digital pins? In which case how does the code work? The sepaby rebecca.palmer - Firmware - mainstream and related support
> Thing is if I try and measure the current between > the turnpot and the ground connection there is > nothing there. I think you should be measuring voltage, not current. Also try checking continuity from the Polulu's enable pin to the ATmega.by rebecca.palmer - Sanguino(lolu)
> no voltage showed on this particular > board which is connected to the y-axis. No voltage where? The power pin, the current-setting pot, or the motor output? > Would I be able to test the continuity for this > between the power access point and the pololu > voltage points? Yes, and good idea. (A Polulu has two power supplies, logic (usually 5V) and motor (usually 12V); checkby rebecca.palmer - Sanguino(lolu)
Can't be done: steppers inherently need a controller to do anything more than hold a position. Either buy/build a controller (given the 5.4A printed spec, if you want full torque you'll need a higher rated one than those usually discussed here), or if the motor can be removed, sell it and buy an actual DC motor.by rebecca.palmer - Stepper Motors, Servo Motors, DC Motors
The thermistors and endstops would need to be run at 3.3V, to avoid sending an out-of-range signal back to the Due; probably the easiest way to do this would be to replace the RAMPS 5V supply by 3.3V throughout. The heater control MOSFETs may also require changes, as too low a control voltage will only partly turn them on, causing them to overheat. Firmware that only used the Arduino librariesby rebecca.palmer - RAMPS Electronics
That would only work at speeds high enough to reliably detect the back EMF ripple (which would be in sync with the rotation); I haven't done a full analysis, but suspect it would be far too easy to lose "steps" when moving slowly (e.g. changing direction, which X and Y have to do often).by rebecca.palmer - Stepper Motors, Servo Motors, DC Motors
> WRITE(Y_DIR_PIN,!INVERT_Y_DIR);WRITE(E1_DIR_PIN,INVERT_E1_DIR); Missing ! (negation, i.e. - direction): if the Y has one, the E1 needs to as well. Also, these two aren't the only places where Y_STEP_PIN, Y_DIR_PIN or Y_ENABLE_PIN is used: don't forget to do the others. > and pins.h would become: No: leave pins.h unchanged. (This is where the compile error came from.) > Question- thby rebecca.palmer - Firmware - mainstream and related support
(Since this is a Sanguinololu not a RAMPS, can someone move it to the Sanguino forum?) If you installed the firmware yourself, check that its Y pin settings (probably in pins.h, configuration.h or similar) match your hardware. Check for short/open circuits between the processor and Y driver. The control signals are 0-5V, but the step signals are pulses not sine waves, so your meter's AC rangeby rebecca.palmer - RAMPS Electronics
You don't change the Y to E, you add E1 (in a second write) next to Y. (E1 because that's what pins.h calls the spare socket; you could rename it there to Y2 or something if you prefer, but not to just Y as you can't have two with the same name.)by rebecca.palmer - Firmware - mainstream and related support
> But then again, why would I want to check the > endstops twice...? You don't: just replace WRITE(Y_DIR_PIN,...); with WRITE(Y_DIR_PIN,...);WRITE(E1_DIR_PIN,...); , and the same for Y_STEP_PIN and Y_ENABLE_PIN.by rebecca.palmer - Firmware - mainstream and related support
That suggests you have a config.h for the wrong RAMPS version: pins 26/28 are X on old (pre-1.3) RAMPS but E0 on current RAMPS. The correct RAMPS 1.4 pin settings can be found here.by rebecca.palmer - Firmware - experimental, borrowed, and future
> However, I would add the > additional constraint that the RPi must be able to > program, from bare metal... > every daughter card. As the RPi has GPIOs, that doesn't require a bootloader, only that the native programming mode uses only 3.3V signals, which is the case for most of the newer PICs (including the 18F27J13; there are several existing open source programs to do this, e.gby rebecca.palmer - Controllers