I2c cables

Going through the forum whenever i2c is mentioned DIY seems to be whats mentioned next. for i2c connectivity can i just buy one online readymade or do i have to make one up? I’m thinking of buying a monome crow or teletype and want i2c connectivity.

If i can buy one readymade could someone provide a link? i live in the UK

The main thing is that the signal lines need to be short. The protocol is primarily designed for things on the same circuit board to use, so longer runs can cause problems.

I see, thanks for that. I just came across a bunch of female to female jumper wires online. In theory i should be able to connect 3 of those from monome to ER-301 following SDA, SCL, and GND pins and a perfect connect will be made? (in terms of connectivity at least, actually programming the signal is another discussion)

I believe that should work. I still haven’t used the i2c in the 301, but I use it in electronics projects.

appreciate it

Yes, this should work. I use it. You can use a bit of shrinkwrap to hold the three jumper cables together, so it’s more like “one cable”.
You just have to make sure that the right pins are connected to the right pins. The order of the i2c pins on the ER301 is different than on all the monome modules.
I think mouser and similar suppliers have cables of three female-female jumper cables in one, but they won’t work for ER301, as it needs the pins to be in the same order.
I hope it makes sense.

I think it’s just up-side-down, so standard three wire jumper cables should work. Please correct me if I’m wrong…

EDIT: So it seems that rev7 (pre june 2018) have the order switched, whereas newer (rev10?) have the order the same…

If you have an ER-301 with board revision 7 (i.e. ER-301 manufactured before June 2018), then please go here.

Otherwise, here.

thank goodness i bought mine in 2019. i got scared when i read I had to modify it :sweat_smile: . It seems like all the necessary things are in place probably will get Crow to save hp. thanks for the help