LCD losing registration

denseuropa · February 3, 2017, 10:03am

I connected a reprapdiscount smart LCD to my MPCNC (I admit I didn’t source it from vicious1, couldn’t stand another battle with UK customs).

After a while the image loses registration ( see photos). This happens:
after a variable time (minutes);
Whether powered by USB from laptop or vicious1’s supplied power supply; Resetting the ramps by pressing the button on the ramps side doesn’t correct it; Moving the display away from the ramps and ensuring its leads don’t pass near any obvious electric fields doesn’t stop it happening.

Removing power and then repowering corrects it for a while.

Is this a known issue with a fix, a faulty LCD display or ?

vicious1 · February 3, 2017, 10:07am

I have no issues with buying from other sources, It just answers a hundred questions when I know if it came from me or not.

I have never seen this, on a reoccurring basis. What firmware are you using? Make sure you are on my RC7 and make sure your ug8lib is correct/updated.

denseuropa · February 3, 2017, 10:27am

Using the firmware that was in the ramps when you supplied it, haven’t flashed the Arduino yet. When i interrogated the ramps using the relevant M code and repatier it reported version 7 ( I can’t remember the exact string but I wanted to check it wasn’t RC8)

vicious1 · February 3, 2017, 12:12pm

I am not sure but I have 2 ideas. For some reason I think some of the pins have a coating on them in this batch. I would start by at least taking the lcd header on and off a few times, or even separating the mega and ramps. I just had this fix a board yesterday.

If that doesn’t help re-flash rc7.

If you got the ramps from me it was tested with an lcd through a test script and driver adjustments.

denseuropa · February 4, 2017, 7:22am

Repeatedly separating the header from the ramps board and separating the ramps from the Arduino to clean up the contacts did not cure it. I also made up 2 ICD cables to check if the fault was there, it wasn’t.
I left the system on to check if it was a component warming up and stabilizing. The display progressively shifted until after a couple of hours it displayed the attached image which I think are Chinese hieroglyphs.

Out of interest on the info screen the X,Y and Z letters alternate between the character and a “?” at about 1-2 seconds intervals. The rest of the display is stable. Is this normal?

Also moving the MPCNC under manual control with repatier the X,Y and Z coordinates on the LCD display correctly and don’t flicker.

I haven’t reflashed as this feels electrical to me and as you said you tested the Ramps before dispatch.

I’m inclined to put this to one side as experience and get on with finishing/ tidying up the MPCNC (I still have to trim all those cable ties!) unless anybody has any other ideas?

Dennis

vicious1 · February 5, 2017, 8:58am

The question mark thing is normal. I’m not sure what to look for I have never seen this issue before.

nppc · February 5, 2017, 2:29pm

I have same problem with LCD sourced from EBay. I think this is LCD problem, mosprobably a batch of LCDs with wrong components or something similar.

Pavel

denseuropa · February 17, 2017, 12:59am

Update on the smart controller screen registration issue. I purchased a replacement controller (in a bundle that included ramps 1.4, Arduino and drivers (UK source). The screen and the encoder work perfectly demonstrating that the original fault was in the display module. However the switch built into the encoder is very intermittent. Shorting the pair of contacts works every time demonstrating that the encoder is faulty.

As part of an order from vicious1 I had also ordered a replacement screen which after 8 days clearing UK customs and getting delivered works perfectly.

All 3 modules are visually identical, attributed to www.bigtree-tech.com. So I now have 1 working controller and if I get keen I may swap the encoder/ switch from the original board into the second board to create hopefully another working board. I would source a new encoder but the identification code on the reprap.org wiki site (BC111E5244B2) is one that neither I or Google can recognise. Does anybody know how many steps / 360 degrees the original encoder has or what that encoder is?

Dennis