I2C Bluetooth Module

Hello everyone,
My project I am trying to accomplish requires that UART communication is only active when a usb cable is inserted into the circuit (which has been worked out already) as to free up the UART pins on a 328p for use in a matrix during normal operation. With that said, I still want to impliment Bluetooth communication while in operation. I was wondering if there are any modules out there that are arduino friendly and could communicate on the I2C bus (I have three other sensors already planned for the bus do this would be my best option). I found a couple options but they were all their own micros that would need programmed by me.

Just wondering if something like this is possible with an off the shelf part with no programming other than the arduino side required. Let me know what you think. Thanks

No idea. But you can consider SoftwareSerial for communication with a bluetooth module (does come at the cost of two pins). Also don't forget that you can use analog pins for digital functions.

Which board? There are a few 328 based arduinos.

I'm creating my own smd pcb for a LED watch project based on the 328p (hence the custom dual purpose UART line circuitry). The project is intense involving tri-state logic on 16 pins to control the 120 LEDs (60 bicolor) along with an accelereometer, rtc, and ambient light sensor on I2C. Kinda put myself into a corner on pin allocation to do bluetooth but I'm hopeful. I'll link some pictures when it's all completed for sure.

Just to show I'm not bs'ing lol

I believe you. A schematic would have been more useful though :wink:

Would help me too at this point haha, designing hardware to pcb needs was my priority. Doesn't do much good if you have to tear up half the design to make it work irl.

Very old topic I know.
But these things get searched.....

You 'could' I2C-ify the Bluetooth module yourself.

I have a YX5300 MP3 player and a Buetooth module on the same project.
Both are UART and both being used on a Pro mini.
I want to keep software to a minimum as I have a lot to squeeze into the 328p chip.

So. I made an ATTINY85 as an I2C to UART chip.

I send an I2C command from the 328p.
The ATTINY85 picks it up and converts it to a format that the YX5300 understands and the module plays a sound.
No need for software serial.

I'm sure something similar could be done for a Bluetooth module too.