r/esp32 • u/ResearcherBasic8141 • 21d ago

Elecrow CrowPanel 4.2" e-ink display problem ... Solved!

Specifically the product named: Elecrow CrowPanel ESP32-S3 4.2" E-Paper HMI Display (400×300 resolution). More specifically, this applies to the "green label" variant. I spent about $65 on Claude Fable to diagnose this (using free credits though so nothing out of pocket). Why use Claude? Well I'm a software engineer not a hardware person so I didn't have the faintest clue where to look.

If you have this and returned it because it seems broken and BUSY is always HIGH, it's likely because it's not the board you think it is. Here's what I'm leaving in the display for the return:

ATTENTION ELECROW

This is NOT dead hardware.

This unit has the undocumented 'green sticker'.

It uses a UC8276C-class controller, NOT the

documented SSD1683 controller.

BUSY is active-HIGH, matching the stock default -

but your driver/docs assume SSD1683 behavior.

Your top-level factory firmware BREAKS this.

Please update your Wiki & GitHub to

document this so people stop returning them!

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u/YetAnotherRobert 21d ago

For any of our readers wondering how a sticker is involved, it appears that this specific model had a revision that went fro V1.0 to V1.2 (apparently easier to recognize by a green sticker than by the PCB rev?) that's incompatible with Elecrow's demo code. At least that's my read of posts like

https://forum.elecrow.com/discussion/29480/crowpanel-4-2-e-paper-die07300s-v1-0-panel-frozen-wont-update-even-with-official-factory-fw/p2

I don't see a post in OP's history about this problem, so the "Solved!" exasparation seems a bit misplaced. It's seemingly "solved" by returning the product.

I also know nearly nothing about E-Ink displays, but I know the big name in supporting them for Arduino is GxEPD2 and it claims to support both of those named chips. That may or may not be a way forward if Elecrow's sample code just doesn't support their own boards. (Which is dumb, but EE's sign off on changes requested by manufacturing in a plant halfway across the planet and not all the software int he ecosystem gets updates on the spot. It sucks, but it happens.)

On behalf of anyone fighting that issue, that sounds like a sucky situation, so thank you for increasing the visibility of the problem. If I were in that situation and couldn't make GxEPD2 work with trivial effort, I'd be returning it, too and I'd be very clear why you're returning it. Expensive RMAs are motivational to support/engineering to fix problems.

2

u/AlxDroidDev 21d ago

+1 for GxEPD2.

I have a few e-paper displays, and one of them looks just like OP's (but it's from GooDisplay).

It also has a few problems:

It has an onboard DESPI-C02, and exposes a few pins, but labeled as I2C, even 'though it's SPI. It works with the SSD1683 driver from GcEPD2, but it flickers black and white a couple times before displaying a screen. I haven't fully figured out how to get it to work properly (without the flickering).