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Assistance Needed: Delayed Response in I2C Communication on RP2040/PICO Board

Posted: Wed Jan 08, 2025 7:27 am
by sureshsoft
Hello everyone,

I am facing an issue with I2C communication on the RP2040/PICO development board, and I hope to get some guidance to resolve it. Here's the situation:

Delayed Response:
I observed a delayed response in I2C communication, specifically when updating characters on a 20x4 LCD connected via an I2C-to-IO expander IC. Updates occur one character at a time, leading to noticeable delays.

Frequency Configuration:
I have tested the board with a maximum frequency setting of 64 MHz in the configuration (the maximum possible frequency is 135 MHz).I can't find the setting above 64MHZ.

Additional Notes:
I used the same configuration code with an ESP32, which worked perfectly without delays.
The issue seems specific to the RP2040/PICO setup.


Regards
Suresh B

Re: Assistance Needed: Delayed Response in I2C Communication on RP2040/PICO Board

Posted: Wed Jan 08, 2025 9:07 am
by mnfisher
Please post a program demonstrating the problem.

Martin

Re: Assistance Needed: Delayed Response in I2C Communication on RP2040/PICO Board

Posted: Wed Jan 08, 2025 11:22 am
by sureshsoft
Hello Martin,

I wanted to share an issue I've encountered while working with my setup. Here's what happened:

My Pico I2C is connected to an I2C-to-GPIO extender module, which is in turn attached to a 20x4 LCD module. I've loaded the attached program and observed that the LCD updates character by character. While this works correctly in the Flowcode simulation, there seems to be an issue with the physical update.

Interestingly, the same configuration and setup work as expected with an ESP32, which leads me to believe there may be a compatibility or implementation issue specific to Flowcode or the Pico. Unfortunately, I'm unable to pinpoint the exact problem.

Your insights or suggestions on this would be greatly appreciated.

Best regards,
Suresh B

Re: Assistance Needed: Delayed Response in I2C Communication on RP2040/PICO Board

Posted: Wed Jan 08, 2025 1:21 pm
by medelec35
Hello Suresh.
Instead of LCD using Software mode @ 100KHz, Select Channel1 and change Baud Select to 400KHz.

Re: Assistance Needed: Delayed Response in I2C Communication on RP2040/PICO Board

Posted: Thu Jan 09, 2025 11:32 am
by sureshsoft
Hello Martin,

Thanks. It's working fine. Also, the interface with the I2C slave device(XL9555) is not working. Please cross-check any configuration or missing points in my project.

I need an SPI sample program on Flowcode, Is it possible to share ?

Regards
Suresh B