Hey guys!
First time posting, but this forum has been a really great source of information - thanks!
I've built a project that requires an I2C communication bus between two microcontrollers (Teensy 3.2 is SLAVE).
I've configured the EXTERNAL_PULLUPS on the teensy 3.2 I2C library.
The difference in my question compared to other I2C voltage mismatch questions online, is that I need the ability to change the MASTER controller that is being used (depending on a specific situation) and the two MASTER microcontrollers I have operate on 5V and 3.3V respectively.
In the demo phase, I was just using the 5V MASTER and used pull-up resistors to 5V accordingly.
Moving past the demo phase, I thought I'd just try and see if the 5V pull-ups worked with the 3.3V MASTER as per my reasoning below... and it did.
In my understanding, the 3.3V I2C bus will still work albeit with the 1.7V potential drop across the pull-up resistor wasting power.
My big question is firstly, is my reasoning above right? and secondly, are there any hardware specifics with the Teensy that might damage the board in the future (I'm thinking that due to the bi-directional communcation of I2C something bad might happen)?
Thanks in Advance!!
First time posting, but this forum has been a really great source of information - thanks!
I've built a project that requires an I2C communication bus between two microcontrollers (Teensy 3.2 is SLAVE).
I've configured the EXTERNAL_PULLUPS on the teensy 3.2 I2C library.
The difference in my question compared to other I2C voltage mismatch questions online, is that I need the ability to change the MASTER controller that is being used (depending on a specific situation) and the two MASTER microcontrollers I have operate on 5V and 3.3V respectively.
In the demo phase, I was just using the 5V MASTER and used pull-up resistors to 5V accordingly.
Moving past the demo phase, I thought I'd just try and see if the 5V pull-ups worked with the 3.3V MASTER as per my reasoning below... and it did.
In my understanding, the 3.3V I2C bus will still work albeit with the 1.7V potential drop across the pull-up resistor wasting power.
My big question is firstly, is my reasoning above right? and secondly, are there any hardware specifics with the Teensy that might damage the board in the future (I'm thinking that due to the bi-directional communcation of I2C something bad might happen)?
Thanks in Advance!!