Arduino Leonardo freezing on start with MCP23017 rotary encoders examples codes

[tainalo2]

Describe the bug
When starting Leonardo with MCP23017 examples code implement, if SDA linked then arduino freezing.

To Reproduce

• Link an MCP23017 to an arduino Leonardo as explain in documentation
• Push official MCP23017-RotaryEncoder-No-Interrupts.ino code without change
• Reset Arduino Leonardo after upload
• Arduino is freezing and not appearing in PC USB device
• Unlink SDA and Reset
• Arduino appearing on PC USB but you can't use the MCP23017

Expected behavior
Expecting not freezing and using rotary encoders over MCP23017

Code
Link to example test : https://github.com/tttapa/Control-Surface/blob/main/examples/1.%20MIDI%20Output/3.%20Rotary%20Encoders/MCP23017-RotaryEncoder-No-Interrupts/MCP23017-RotaryEncoder-No-Interrupts.ino

Precision
I have test my same installation with the Adafruit_MCP23X17.h and a button and it's working, to verify if my MCP23017 is working.

(thank you for your amazing library !)

[tttapa]

Thanks for the detailed report! I can't seem to reproduce the issue you describe with my setup (Official Arduino Leonardo, Arduino AVR Core 1.8.6, Control surface main 39182bb).

Could you list the versions of the libraries, cores and tools you're using?

You can try removing the Wire.setClock() line, I don't think the ATmega32U4 supports anything above 400 kHz.

[tainalo2]

Hello,
SOLVED : i have comment "Wire.setClock()" line
Very thanks !

More precision :

• Using main branch of this git at 02/05/2023 15H30
• Arduino IDE : 2.1.0
• Not official Leonardo, but a clone from Keyestudio (https://www.keyestudio.com/products/keyestudio-atmega32u4-leonardo-r3-development-board-1m-micro-usb-cable-for-diy-project)

Now i will try to create a prototype of 16 rotary encoders with two MCP23017