SD not working with Megatronics V2.0 with SainSmart LCD

About the only real issue I see with the Smoothie board is the fact that it does not support thermocouples which is the main reason I selected the Megatronics board to begin with. Thermister are ok but any real serious temp control can only be accomplished with therocouples.

- Paul

Can you tell me if this is Right way to connect it

Can you also tell me or send me the eBay link
For the heated bed thermistor
Thank you

i attached a pic can you tell me if it is correct

can you tell me which thermistor for the heated bed thank you so much
this think sucks with out documents

any reason why they sell this with out instructions

I can not tell without a complete picture of the cable from one end to the other. It looks right but I can not be sure. I can tell you if you get this wrong it will cause the 5 volts to be shorted to ground when you click the switch so that is not a good thing to be sure.

- Paul

I think you should be ok with these thermisters from ebay.

Thermisters

- Paul

Hope this picture is better

i made a better picture hope this is ok let me know thank you

That looks like how mine are wired. Try tapping the switch QUICKLY, and see if the LED on the endstop board lights up. If it does, they are wired correctly. If not, don't tap it again as you'll risk blowing your board out!

When you have the switches smoke-tested, you can then test them with an M119 command to read each one's status via software.....

it dose light up thank you so much you guys are the best

Edited 1 time(s). Last edit at 04/13/2014 09:41AM by papo.

Hi Paul can u tell me if I need jumper for the ramps
Or a pic of your board

Are you asking about the stepper motor driver jumpers? If so then I would say yes, because it is critical to get the DEFAULT_AXIS_STEPS_PER_UNIT setting correct for it to work. I have a Megatronics board which is really nothing more than a ramps board that has been re-designed to make it a single board with the Ardunio built in. Also the added the extra thermocouple circuit to it as well. Other than that the two are identical in almost everyday. If anyone is trying to decide which one of these to get then the Megatronic board is the one I recommend. Mainly because of the thermocouple but also because it has a much better layout for wiring them.

I have installed all three jumpers under each stepper motor driver on the board. There really is no need for a photo as there are only three jumpers under each driver board on the ramps unit. The Megatronics board does have four jumpers but that is only for a different driver board option. Typically you will only need the three.

The calculation to get the DEFAULT_AXIS_STEPS_PER_UNIT (Found in Marlin Configuration.h file) can be done using this online calculator: Steps Per Unit Calculator
You know you have this close to being correct if you are somewhere withing 50 to 100 range for each axis. The only one that is different would be the Z axis and that should be somewhere around 2200 to 2700 depending on the pitch of the screw you are using.

#define DEFAULT_AXIS_STEPS_PER_UNIT {78,78,2560,100}

I know a lot of people place a calculation into this definition something like: 200*8/3 or 760*1.1
I am not sure why they do this because the outcome is exactly the same so why not simply it so a human does not need a calculator to read it LOL. Kinda like my example above right?. The last digit in this definition is for your extruder stepper motor and depending on your hot end/nozzle width/stepper motor/temp/drive gear or direct drive bolt will depend on where you will set this variable. Setting it too high will result in trying to feed too much plastic into your extruder at one time which will result in a clog or jam. Fortunately my print head said it could run at 40m/s which gave me a ball park range to start from.

The best rule of thumb here is to start off slow. Use smaller numbers and increase until you see a problem then back off a little bit.

I know you did not ask these question and you only asked about the jumpers but inevitably you will be asking these questions. I know this because that is what happened in my case. I did not have anyone to give me these answers I did it on my own but you can certainly benefit from my own personal experience here.

- Paul

it was working fine i moved printer bed slid to the back could that have damaged the board the lcd displays fine when i plug the usb in to it
i flashed it with marlin it looks fine until i plug in the 12 v the stepper motor chip get hot the led turns dark

Is their a place to get my megatronics v2.0 fixed

How old is it? If it is new just get an RMA and get a replacement board. If not then contact the company you purchased it from.

- Paul

I got the same problem with my Megatronics 3.0 and the Sainsmart Full Graphics LCD.

All work ok, but SD card (on LCD panel) it doesn´t.

But reading all this post threads it looks like there isn't solution to this problem. Where's the problem? On the LCD SD reader? On the Megatronics board? Marlin software? I'm think its better go for an external SD reader, and do not waste more time.

Is there a full graphic display, SD and keypad, that sure know will work with the Megatronics V3 board?

Regards.
Marcos

(Sorry, my English is bad)

The necessary signal pins to drive the SD slot are not sent to the Megatronics 2.0 board via the provided LCD interface connectors. The design never had provisions for an external SD socket, since the Megatronics 2.0 has one on-board.....

Found a simple workaround of the Sd card problem for the lazy. I googled Sd to micro sd converter and found that sd extenders are a thing. For 5-10 bucks you can get a micro sd "card" with a 10-24 inch going from it to a sd card reader. I bought one and will say how it worked out.

Good find! They are apparently used to extend MicroSD slots for car stereo and GPS units. Here's one on Amazon where reviewers mention using it with Arduino boards:

http://www.amazon.com/Manufacture-Sdhc-micro-Reader-Extension-Cable/dp/B0085GGO92/ref=pd_sim_sbs_pc_1?ie=UTF8&refRID=0Y2V7VY0HTZVMF9WKR37

There are others out there, so feel free to shop around.....

I looked into it. I hoped it was a firmware problem but it is not. It is just a bad megatronics design. SD cards are connected through SPI bus. On Megatronics LCD panels connect to LCD and keypad header but neither of them has SPI, There is ICSP header on the board, but I do not think there is a adapter on the market for LCD panel that uses it so only way to make SD card reader to work is to mod existing adapters.

Given up from the LCD SD card reader because I don't want to jumper or solder my board, I brougth a external SD reader from ReprapWorld, made a cable to attach it pin-to-pin to the Megatronics external SD connector but also doesn't work.

I asked to RRW support but they don't answer to my mail.

It receives power on pin 1 and gnd on 7 but not SD Card is detected when inserted. The inboard micro-SD works OK.

I don't know if it need to change any configuration on pins.h

On the Megatronics SD pin out:

SDOUT External SD card header
1. 5V
2. A2
3. MISO
4. MOSI
5. SCK
6. D53
7. GND
8. Not connected

And in the external SD pin out:

Megatronics Header to connect the board to Megatronics (SDOUT) or
RAMPS (SD RAMPS / AUX3 / SPI)
1. +5V
2. DIG2
3. MISO
4. MOSI
5. SCK
6. CS
7. GND
8. DIG3





Any ideas?

Are you connecting megatronics SDOUT 6. D53 pin to exSD 6. CS?

Phisically yes, but I din't made any modifications on pins.h, just connect pin-to-pin as RRW say on their SD manual.

Only these lines are for the SD card on pins.h

#define SDPOWER -1
#define SDSS 53
#define LED_PIN 13

Edited 1 time(s). Last edit at 11/15/2014 08:07AM by marcossf.

I do not think you need to change pins.h as expansion should be using the same pins as onboard SD. Only think I can advise is to recheck your wiring, as it either a wiring is wrong or SD expansion board is faulty. Just too make sure are you using this pin out for header?


Edited 1 time(s). Last edit at 11/15/2014 04:21PM by Endlane.

Solved!

The pins, the cable I made, and the SD reader was ok. The problem was the SD card.

I'm trying with some 1 and 4Gb old SD cards that I have at home. Bart form RRW told me that if could try with another SD because some are problematic with SPI.

I put a 8Gb Samsung microSD on an adapter and inserted in the SD reader and it works as expected.

No firmware or wiring was changed, just the microSD (+adapter) instead SD card alone.