Inkplate6 text displays but graphics don't appear

TECHNICAL SUPPORT Inkplate
1

Customer:

I received the Inkplate6 but it didn’t work in peripheral mode - only functions returning data through console, none displaying on the screen.

I tried flashing an image from an internet sample project, which could display the image, but none of the information text about connecting to wifi appeared.

Now I have a simple sketch where all I do is create a circle and display it, then write text to the screen, and then display again. None of which give any result.

I tried flashing with the board type set to:

  • Soldered Inkplate6
  • Soldered Inkplate6Plus
  • E-Radionica Inkplate
  • E-Radionica Inkplate6Plus

Originally submitted via email support on 24 August 2023. Migrated to the forum for community visibility.

2

Soldered Support:

Can you send the sketch you are using?

Can you send a screenshot of the Tools menu from your Arduino IDE?

3

Customer:

Attached are the files you requested.

Attachment omitted in migration: w4p80m5hzH.png

Attachment omitted in migration: Test_inkplate6.ino

4

Soldered Support:

If you have the purple board, those settings should be correct, assuming the correct port is selected. I recommend reducing the upload speed to one lower value to ensure stability.

Do you successfully upload the code to the Inkplate and get the “Done uploading” message in the Arduino IDE?

If you do get the “Done uploading” message, try unplugging and plugging the e-paper flex connector. Sometimes it gets fuzzy during shipping.

Attachment omitted in migration: DSC-9005-Edit.jpg

5

Customer:

I tried both of your suggestions for fixing the issue. I also tried an even slower upload rate, but I was not successful.

The display still does not display anything at all.

6

Soldered Support:

Can you answer this question - it’s key to the troubleshooting process: Do you successfully upload the code to the Inkplate and get the “Done uploading” message in the Arduino IDE?

Which COM port (Tools->Port) do you have selected in your Arduino IDE?

7

Customer:

The COM port I use depends on which USB port I use and whether I have other USB devices connected. This time it’s COM5.

The status message after upload is “Wrote 304192 bytes (155944 compressed) at in 13.9 seconds (effective 174.6 kbit/s)… Hash of data verified.”, after which the board resets.

Attached is a screenshot of the terminal.

Attachment omitted in migration: image.png

Attachment omitted in migration: image.png

8

Soldered Support:

You mentioned that a sample project successfully displayed an image on Inkplate in your original email - so we know the e-paper display is working, which is a great start.

I’ve added some things to your sketch. Try uploading it and looking at the Serial monitor.

Use the board definition which worked for displaying that image (I guess this is Soldered Inkplate6).

Let me know if this sketch does something and if you can see the debug messages on Serial (make sure to set the baud rate to 115200 on the Serial monitor).

Attachment omitted in migration: Test_inkplate6.ino

9

Customer:

I tried the supplied sketch.

It now displays the text “INKPLATE” on the screen - success!

But the circle is still nowhere to be found.

Here is a screenshot of the serial monitor with the debugging messages:

Attachment omitted in migration: image.png

10

Soldered Support:

It seems your contrast might not be well adjusted. Try replacing the circle command with:

display.fillCircle(300,200,100,BLACK);

This should make the black filled circle appear. The ‘4’ in the current drawCircle command is a shade of gray - we initialized Inkplate in 3-bit mode (which is 3-bit grayscale, on line 3 of the code I sent you) and it may be too light on the actual display to be seen. The reason this is happening is the VCOM needs to be adjusted. VCOM is a small negative voltage used to drive the e-paper display and adjusting it can make images appear different.

Check if your e-paper display has a sticker on the flat cable with a number like -1.5 - that would be the VCOM voltage for that specific panel. Your particular panel may not have come with this sticker, so the VCOM was set approximately.

Here’s how to improve it:

  1. Open the example in Examples>Inkplate6>Diagnostics>Factory_Programming_VCOM
  2. On line 50, change the EEPROMaddress to some other number like 3, 6, or 12 (if you want to change the VCOM voltage again you always have to change this number)
  3. On line 91, remove the call to testPeripheral(); or comment it out
  4. Upload the sketch and open Serial monitor at 115200 baud
  5. You will be prompted to enter the VCOM - start with -1.2 and check the contrast of the resulting image
  6. To make the image darker, go further into the negative (-1.3, -1.4 and so on, using 0.1 as a good step), and vice versa

See if this makes a difference. You can also always use Inkplate in 1-bit mode.