OLED SSD1306 I2C Address

[jgu1]

Hi all!

I report a bug for these tiny display In Fc9for a while ago. Do you have FC8, try to make a test in this SW work fine there, But not in FC9.

viewtopic.php?f=3&t=790

Br Jorgen

[MJU20]

I think it's a strange timing problem. And that could be the reason the display is updated very very slowly (like 1 minute to draw a small text on the display or clear the display).

These are screenshots from my logic analyser with several different settings for the I2C baud rate:

Baud rate in SSD1306 I2C properties = 100kHz

100khz.jpg (35.27 KiB) Viewed 5713 times

Baud rate in SSD1306 I2C properties = 400kHz

400khz.jpg (40.31 KiB) Viewed 5713 times

Baud rate in SSD1306 I2C properties = 1MHz

1Mhz.jpg (46.12 KiB) Viewed 5713 times

Even with a custom baudrate it keeps 490hz...

I hope that with this information Matrix can fix this problem really fast.

[MJU20]

And this is with the Arduino/ESP32 library with Adafruit sketch..

This one works..

[jgu1]

Hi MJU

Well spottet So I was rigth viewtopic.php?f=3&t=790

Have you testet in FC8 (Arduino) it works there

Jorgen

[MJU20]

Not tested in FC8 because this project has to work with an ESP32 and that wasn't supported in this version.

BTW: I think this problem may occur in the SPI version too. I've tested the ESP with the SPI version of the SSD1306 and this also didn't work..

[BenR]

Hello,

With the I2C timing problem you've highlighted. Please can you confirm the target MCU you're using and also the I2C channel you're using and I'll investigate for you.

[MJU20]

Thank you Ben,

I'm using an (NodeMCU) ESP-Wroom-32 (version 1.1).
The I2C channel I'm using is "software" on pin A21 (SDA) and A22 (SCL). (same as the Arduino sketch)

BTW: I2C Channel 1 in FC proposes pin B4 on the board (A36), but this is not available on the board.

[MJU20]

any news on this one?

[LeighM]

Using software aka bitbang I2C is very much a last resort on ESP32 due to it running an RTOS, hence timings can't be guaranteed and tend to stretch considerably.
Are there any hardware channel I2C remap pins that you can use?

[MJU20]

I will look into remapping the I2C.

Too bad it took a week to read this and meanwhile the display was tested with an Arduino sketch using the same IO's as those I used with FC.