Build of Deployable Units

[Penri]

Good idea!

[TerryJC]

Before the above though, I'll go back to basics and fit one of the screens directly to the Pi and run the example code to establish that these boards actually work!

Bad news I'm afraid. The new batch of screens don't seem to work even when connected as per the User Manual. I haven't tested them all yet, but one doesn't display anything and at least one other displays striations over the Andy Pandy image.

Presumably Penri, you received these some time ago, so returning them for a refund or replacement might not be easy. Any thoughts on this?

After lunch I'll work through the rest to see how bad they are.

[Penri]

Terry

Just checked, the return window for the units closed on 18Mar21, let me know what the overall status is and I'll see what I can do.

Penri

[TerryJC]

Will do.

[TerryJC]

None of the five screens that you gave me on Wednesday are working properly:

1. One has the black and Blue wires transposed in the white connector. Needless to say it doesn't work.
2. Two appear to be wired OK, but are dead.
3. The final two work (after a fashion). The display is dim compared to the 'reference' models and the Andy Pandy image has striations and flickers slightly.

The original set of screens came in boxes labelled 'Waveshare' and had nothing else on them. The later set set of screens came in boxes labelled variously 'Makerfocus' on the box and separately labelled 'MakerHawk I2C OLED Display... 5 V IoT Things for Arduino' on a separate stick-on label.

Apart from the wiring error above, I wonder if these displays are targeted only at Arduino and actually only work with a 5 V power supply input?

The Waveshare ones work on both 3.3 and 5 V and there is an internal voltage regulator to reduce the internal voltage to 3.3 V.

[Penri]

Terry

Thanks for the analysis.

I have contacted the seller via Amazon's contact process and stated the issues, will have to wait and see what happens.

I appear to have bad luck almost every time I use Amazon, I'm currently awaiting the arrival of another item that running very late. I prefer to use eBay but could not find a suitable module at the time I looked hence I used Amazon.


Penri

[Penri]

Following a discussion with Terry I have placed an oder for 5off Waveshare display modules from a supplier in Germany via eBay.

[Penri]

Delivered today, 5 Waveshare display modules.

Terry, I'll arrange to deliver them to you in the next couple of days.

[TerryJC]

OK.

[TerryJC]

OK. There's good news and there is bad news.

The good news is that all five of the new screens seem to work apart from one; see below.

The bad news is that one of the screens has a permanent white strip running vertically up the display:

OLED_Startup.jpg (71.34 KiB) Viewed 556 times

OLED_Image.jpg (88.63 KiB) Viewed 556 times

Ignore the diagonal band on the image; that's an artefact of the camera.

So none of the the displays seem to have the interference seen in the Maker types, but this certainly looks like a fault to me.

There are a couple of things that I can do before we start complaining to the seller:

1. Try this screen on a bare Pi running as intended by Waveshare. I'll run the Example code to see what happens.
2. If Item 1 works, I'll try this screen on the second Interface Board in case it's susceptible to noise from the first board.

Also I don't seem to be able to get anything on the 4th screen even though I've seen that screen working on both Interface Boards in the past. That may be a fault that has developed on my Board; I need to do some more diagnostics to be certain.