Attempting with XAOI Seed ESP32C6

[technash85]

Hello,

Thanks for the very attractive project and for keeping up with the API changes. As title states, I am attempting to drive Waveshare 400x300 4.2i e-ink display V2 via SEED ESP32C6. I thought this would be the correct wiring (can see output in Arduino IDE where it is communicating with API and getting replies but no screen output):

BUSY = 3 CS = 0 RST= 2 DC=1 SCK = 8 MISO = 9 but not connected MOSI = 10

ANY help -- or pointing in the right direction even -- is much appreciated.

[G6EJD]

Using Dn GPIO pin numbering is only going to work if you have selected the correct board type in the Arduino IDE, which for your board must be the XAOI ESP32C6, then: BUSY = D3 or GPIO-21 CS = D0 or GPIO-0 RST= D2 or GPIO-02 DC = D1 or GPIO-01 SCK = D8 or GPIO-19 MISO - not connected MOSI = D10 or GPIO-18

So you have two approaches for the display object: // Connections for e.g. XAOI ESP32C6 will only work if you select the board type as XAOI ESP32C6 (maybe) static const uint8_t EPD_BUSY = D3; // to EPD BUSY static const uint8_t EPD_CS = D0; // to EPD CS static const uint8_t EPD_RST = D2; // to EPD RST static const uint8_t EPD_DC = D1; // to EPD DC static const uint8_t EPD_SCK = D8; // to EPD CLK static const uint8_t EPD_MISO = -1; // Master-In Slave-Out not used, as no data from display static const uint8_t EPD_MOSI = D10; // to EPD DIN

Then:

GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/CS/ EPD_CS, /DC/ EPD_DC, /RST/ EPD_RST, /BUSY/ EPD_BUSY));

OR:

// Connections for e.g. ESP32C6 using GPIO numbers static const uint8_t EPD_BUSY = 21; // to EPD BUSY static const uint8_t EPD_CS = 0; // to EPD CS static const uint8_t EPD_RST = 2; // to EPD RST static const uint8_t EPD_DC = 1; // to EPD DC static const uint8_t EPD_SCK = 19; // to EPD CLK static const uint8_t EPD_MISO = -1; // Master-In Slave-Out not used, as no data from display static const uint8_t EPD_MOSI = 18; // to EPD DIN

Then:

GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/CS/ EPD_CS, /DC/ EPD_DC, /RST/ EPD_RST, /BUSY/ EPD_BUSY));

You may also need to try a different display object for your screen type, like this: //GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/CS=5/ SS, /DC=/ 17, /RST=/ 16, /BUSY=/ 4)); // GDEW042T2 400x300, UC8176 (IL0398)

//GxEPD2_BW<GxEPD2_420_M01, GxEPD2_420_M01::HEIGHT> display(GxEPD2_420_M01(/CS=5/ SS, /DC=/ 17, /RST=/ 16, /BUSY=/ 4)); // GDEW042M01 400x300, UC8176 (IL0398)

//GxEPD2_BW<GxEPD2_420_GDEY042T81, GxEPD2_420_GDEY042T81::HEIGHT> display(GxEPD2_420_GDEY042T81(/CS=5/ SS, /DC=/ 17, /RST=/ 16, /BUSY=/ 4)); // GDEY042T81, 400x300, SSD1683 (no inking)

//GxEPD2_BW<GxEPD2_420_GYE042A87, GxEPD2_420_GYE042A87::HEIGHT> display(GxEPD2_420_GYE042A87(/CS=5/ SS, /DC=/ 17, /RST=/ 16, /BUSY=/ 4)); // GYE042A87, 400x300, SSD1683 (HINK-E042-A07-FPC-A1)

//GxEPD2_BW<GxEPD2_420_SE0420NQ04, GxEPD2_420_SE0420NQ04::HEIGHT> display(GxEPD2_420_SE0420NQ04(/CS=5/ SS, /DC=/ 17, /RST=/ 16, /BUSY=/ 4)); // SE0420NQ04, 400x300, UC8276C (OPM042A2_V1.0)

[technash85]

Thanks so much! Will give it a whirl this evening so time and report back. What you've written makes perfect sense! I'm still pretty new to the SEED versions of ESP32 and this cleared quite a few things up for me about pin numbering in general on them.

[technash85]

K. Gave the first part of it a try. I'm getting this error when trying to compile now (sorry if it is something obvious and I really appreciate you writing back to me!):

C:\tools\Arduino\eWeather\Waveshare_4_2\Waveshare_4_2.ino:73:62: error: expected primary-expression before '/' token 73 | GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/CS/ EPD_CS, /DC/ EPD_DC, /RST/ EPD_RST, /BUSY/ EPD_BUSY));

The carrot symbol is pointing at the ( in (/CS/.

Here's the rest of the output:

C:\tools\Arduino\eWeather\Waveshare_4_2\Waveshare_4_2.ino:73:61: error: expected primary-expression before '(' token 73 | GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/CS/ EPD_CS, /DC/ EPD_DC, /RST/ EPD_RST, /BUSY/ EPD_BUSY)); | ^ C:\tools\Arduino\eWeather\Waveshare_4_2\Waveshare_4_2.ino:73:62: error: expected primary-expression before '/' token 73 | GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/CS/ EPD_CS, /DC/ EPD_DC, /RST/ EPD_RST, /BUSY/ EPD_BUSY)); | ^ C:\tools\Arduino\eWeather\Waveshare_4_2\Waveshare_4_2.ino:73:63: error: 'CS' was not declared in this scope; did you mean 'SS'? 73 | GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/CS/ EPD_CS, /DC/ EPD_DC, /RST/ EPD_RST, /BUSY/ EPD_BUSY)); | ^~ | SS C:\tools\Arduino\eWeather\Waveshare_4_2\Waveshare_4_2.ino:73:75: error: expected primary-expression before '/' token 73 | GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/CS/ EPD_CS, /DC/ EPD_DC, /RST/ EPD_RST, /BUSY/ EPD_BUSY)); | ^ C:\tools\Arduino\eWeather\Waveshare_4_2\Waveshare_4_2.ino:73:76: error: 'DC' was not declared in this scope; did you mean 'D9'? 73 | GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/CS/ EPD_CS, /DC/ EPD_DC, /RST/ EPD_RST, /BUSY/ EPD_BUSY)); | ^~ | D9 C:\tools\Arduino\eWeather\Waveshare_4_2\Waveshare_4_2.ino:73:88: error: expected primary-expression before '/' token 73 | GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/CS/ EPD_CS, /DC/ EPD_DC, /RST/ EPD_RST, /BUSY/ EPD_BUSY)); | ^ C:\tools\Arduino\eWeather\Waveshare_4_2\Waveshare_4_2.ino:73:89: error: 'RST' was not declared in this scope 73 | GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/CS/ EPD_CS, /DC/ EPD_DC, /RST/ EPD_RST, /BUSY/ EPD_BUSY)); | ^~~ C:\tools\Arduino\eWeather\Waveshare_4_2\Waveshare_4_2.ino:73:103: error: expected primary-expression before '/' token 73 | GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/CS/ EPD_CS, /DC/ EPD_DC, /RST/ EPD_RST, /BUSY/ EPD_BUSY)); | ^ C:\tools\Arduino\eWeather\Waveshare_4_2\Waveshare_4_2.ino:73:104: error: 'BUSY' was not declared in this scope; did you mean 'EBUSY'? 73 | GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/CS/ EPD_CS, /DC/ EPD_DC, /RST/ EPD_RST, /BUSY/ EPD_BUSY)); | ^~~~ | EBUSY

Am I supposed to plug in the values or write it just like you've written it in your reply?

[G6EJD]

For some reason the comment asterisks have been striped out so when you see /RST/ change to / RST / or just remove leaving the PIN numbers or names Then /CS/ EPD_CS, becomes EPD_CS, EPD_DC, and so-on

[technash85]

I need to do some more reading on the display library to wrap my head around it some more. I really thank you for all your help! I'm having no luck getting the display to work. I have the Waveshare Rev. 2.2. I do see the code runs, but I think I'm seeing an error come across the serial monitor just before it enters deep sleep.

21:07:37.781 -> E (3795) adc_common: adc_io_to_channel(28): invalid gpio number

[G6EJD]

ADC channels can only be on GPIO 32 or above

its most likely your pin definitions for the display connection that are wrong.

[G6EJD]

The pins you were originally quoting I can now see are wrong for the display connections, the XAIO pins need to be redefined. Search for the C6 variant and make sure you use the MOSI MISO and CLK as a minimum so that most of the SPI bus is correct

[G6EJD]

For the ADC you can use GPIO-1, 2, 3, 4, 5, 6

[technash85]

Thanks for your help! Got it working now!

[G6EJD]

Good bews