Help with Qwiic pull-up resistors with Differential I2C Breakout a part of the system.

Qwiic System
1

I am setting up a Qwiic system as such:

BlackBoard [SPX-14669] ----- Single Relay board [COM-15093] ---- #1 Differential I2C Bus Extender [BOB-14589] ===== #2 Differential I2C Bus Extender [BOB-14589] ----- SparkFun RFID Qwiic Reader [SEN-15191]

On which devices would I need to cut the pads for the Qwiic pull up resistors?

Would it be these:

Single Relay board

#1 Differential I2C Bus Extender

#2 Differential I2C Bus Extender

Or since the wire type has changed:

Single Relay board

#2 Differential I2C Bus Extender

Or just the Single Relay board

This setup is going to replace a BasicStamp 2 with a Parallax serial RFID reader; this has worked for over ten years and has just failed.

This is an entry door that is only unlocked during office hours but is magnetically locked and opened by this system, exit motion detector or by entry intercom.

Thanks for any Qwiic help.

Please provide any information on this issue on the Differential I2C Bus Extender product page so it can be helpful to others using that product.

Thomas White

Tuscaloosa, AL

2

Hi Thomas, and thanks for your post.

You might actually be OK not disabling any pullup resistors at all. Give it a try but if you run into trouble I’d try cutting the jumpers on the relay board. Everything else should be OK as-is.

3

Thanks