Getting RPM OSD working iNav, Speedybee - help please

[tommite]

I'm using a Speedybee F405 Wing App flight controller and I want it to display the motor rpm on the OSD. However I can't get it to register any rpm. I am using an blheli_s esc that I flashed with bluejay, in the config I set the esc protocol to dshot300, in the ports tab (this is one area I'm uncertain) I have tried setting various UARTs to enable the esc telemetry, I don't know which is the correct one (the esc is just connected to S1). To supplement this I tried splitting the esc so that it can also feed into rx4 and gnd and then set UART 4 to enable the telemetry but that didn't seem to work either. The OSD just shows three dashed lines no matter what. So yeah if anyone know how to get this working that would be a great help! If you need anymore detail just let me know

 

[LitterBug]

Hmmm. I thought the newer version (bluejay) was supposed to be bidirectional DSHOT and not need the extra RPM pin. What version of INAV are you running? Maybe I can set up a similar test to figure it out.

 

[LitterBug]

You will need to hook the telemetry pin on the ESC to an unused RX port on the FC. Then enable ESC telemetry on the serial port you connected to. It does not look like INAV has fully implemented bidirectional DSHOT (aka BDSHOT)

 

[tommite]

Amazing thank you, even though I tried that I miswired it so it went into Rx2 not Rx4 haha.
Having fixed that now it is able to read that some rpm values are being fed in, the only problem is that it is giving crazy values, like when it isn't turning it will read like 32k, then as it turns it will vary wildly, do you know how to fix that?