I recently managed to get my hands on some Fly TMC2209 drivers. I can hear you asking though, why am I writing about them, there must be something special right?

I’m not going to go into specifications etc because everyone who comes here will know what a TMC2209 is and what its capable of.

What I really want to point out about these drivers is that, unlike other manufacturers 2209 drivers, when not using sensorless homing, there is no need to remove the diag pin when the motherboard being used has no means to do so. On the underside of the driver, there is a small switch used to enable the diag pin. Other than that bombshell, they are well designed and well made. Definitely recommended.

They can be purchased from the Mellow Store on aliexpress

Like any good maker, I like to buy the cheapest version of something that I can. If buying from two sources gets me something a few £s cheaper then thats what I’ll do.

What did I order?

I ordered an SKR v1.4 turbo (which has a 120Mhz processor compared to the standard 100Mhz processor) and 5 x Fysetc TMC2209 v3. Buying this combination saved me around £5, which in my eyes was worth it.

Whats the problem?

What I didn’t realise is that Fysetc had changed the pinout of the TMC2209 v3 from the earlier versions. This means that the jumper settings detailed on the SKR v1.4 page on aliexpress do not work. This results in a TMC connection error in Marlin and the inability to set the steps, current or use sensorless homing (which is a gimmick I know).

So what now?

Luckily I was able to find a fix for the issue. Even better is that no soldering or modification of the driver is required.

All that’s needed is to add the jumpers as shown (look for the green box) underneath each driver

No more TMC connection errors.