Can somebody confirm if I2C clock stretching works on the RP1?
I'm trying to write code for controlling a Sparkfun LCD-16397 (https://www.sparkfun.com/products/16397) display module via I2C.
It works perfectly on a Raspberry Pi 5, with a 100 us delay after each I2C write, but fails intermittently on a Raspberry Pi 3/4/Zero 2W with almost any delay after write.
The I2C interface on the module is handled by an AVR microcontroller, and although I haven't caught it on my scope, I wouldn't be surprised if the AVR is clock stretching whenever it can't keep up.
From the very beginning, the broken BCM2835 I2C hardware has been a pain, and I'll be glad if it is fixed on the RP1.
I'm trying to write code for controlling a Sparkfun LCD-16397 (https://www.sparkfun.com/products/16397) display module via I2C.
It works perfectly on a Raspberry Pi 5, with a 100 us delay after each I2C write, but fails intermittently on a Raspberry Pi 3/4/Zero 2W with almost any delay after write.
The I2C interface on the module is handled by an AVR microcontroller, and although I haven't caught it on my scope, I wouldn't be surprised if the AVR is clock stretching whenever it can't keep up.
From the very beginning, the broken BCM2835 I2C hardware has been a pain, and I'll be glad if it is fixed on the RP1.
Statistics: Posted by pmunts — Wed Feb 28, 2024 12:03 am — Replies 0 — Views 11