Adafruit .56" display

What is the recommended conductor size to use? How long is too long?
I'm using an Ethernet Cat 5 cable about 8' long to connect the display to Arduino.

I2C is designed for inter-PCB connections. So 8' is to long.
If it works your are lucky, but it can't be recommended to use long wires.

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I2C stands for Inter Integrated Circuit. i.e. it is intended for connecting chips on a single pcb.

In practice it will work reliably up to 300mm or so. e.g. stacked pcbs.
2400mm is way beyond the design of the bus.

However it will probably work ok if you use separate pairs for SDA and SCL. The conductor size is unimportant. Regular Cat 5 is fine.

Don't operate near big electric motors, contactors, ...
It is capacitance and noise pickup that matters.


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you can always add a little boost: Adafruit LTC4311 I2C Extender / Active Terminator [STEMMA QT / Qwiic] : ID 4756 : $7.50 : Adafruit Industries, Unique & fun DIY electronics and kits

Also, wire up the pairs as
pair 1 - Gnd/Gnd
Pair 2 - SCL/Gnd
Pair 3 - SDA/Gnd
Pair 4 - power/power

to give yourself the best chance possible

That's awesome! I will check that out. Thank You
I order one and try it.
My display works great when I plug in with 6" wires. When I go to my 96" it is very slow and sometimes it don't work.

Is there more options to buy these displays and other hardware besides Adafruit?

Similar displays are available on Aliexpress as
7 segment or as
16 segment also.

Sometimes there are offers on ebay with an 8 digit variant from a seller " WtihK"

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