# RPM Filter (Old)

## Offical Betaflight Wiki

[Bidirectional DSHOT and RPM Filter](https://github.com/betaflight/betaflight/wiki/Bidirectional-DSHOT-and-RPM-Filter)

RPM filter will let beetle fly much better.

{% hint style="danger" %}
Enable RPM filter will lose LED function! on V1.0
{% endhint %}

## Blheli\_S ESC Setup

### 1 : Download the special firmware of ESC.

[Link](https://raw.githubusercontent.com/JazzMaverick/BLHeli/JazzMaverick-patch-1/BLHeli_S%20SiLabs/Hex_files_16.9/BB2_H/J_H_30_REV16_9.HEX) - J\_H\_30 ESC firmware for TransTEC 25A ESC. (16.9)

### 2 : Connecting the ESC to computer and then click Flash Other.

![](/files/-M3FxrgXa0-K58j5O0n-)

### 3 : Select the file previously downloaded.

![](/files/-M3FyTSgq9Jygjhx2Qem)

### 4 : Click YES in the next steps.

![](/files/-M3FymyIZncvlV12fFAs)

{% hint style="danger" %}
Remember flash all of the ESCs
{% endhint %}

### 5 : Waiting for it flash done, and then click OK. 

Complete the rest ESC in order.\
It will show ESC version and check if it is correct.

![](/files/-M3FzGJkuRGsUmrj2KI9)

### 6 : Setup Blheli\_S default parameter

Set start up power to 0.38.\
Set PPM Max Throttle to 1640.

![](/files/-MRrP8LJBHgRpoXe0XtU)

## Betaflight Configuration setup

### 1 : Open Betaflight Configuration and go to CLI.

![](/files/-M3FtswwIeje-0yoeRpu)

{% hint style="info" %}
If you want to keep LED blink, set the LED color first and then follow this guide.
{% endhint %}

### 2 : Type following command in CLI.

```
#resource LED_STRIP 1 none
#set cpu_overclock=120mhz
#save
```

{% hint style="info" %}
Only TransTECF411 need type this CLI, TransTECF7 doesn't need.
{% endhint %}

### 3 : Go back to Betaflight Configuration enable Bidirectional Dshot.

Set the motor poles value to 12. (12 for 110X series motor)

![](/files/-M3FuJh87sy1vbl0Osiq)

### 4 : Set Betaflight Dynamic Notch Filter value.

Dynamic Notch Filter Range - **MEDIUM**\
Dynamic Notch Width Percent - **0**\
Dynamic Notch Q - **200**\
Dynamic Notch Min Hz - **90**\
**For Betaflight - 4.1.X**

![](/files/-M3Fw5bryziw5CNYe5PY)

```
#set dyn_notch_width_percent = 0
#set dyn_notch_q = 250
#save
```

**For Betaflight - 4.2.x**

![](/files/-ME1RJRTsnm3LfWLgdsb)

### 5 : Check if the Bi-Dshot work correctly in motor tab.

It will show **E: 0.00%**, indicates that it works great.

![](/files/-M3JokzmEQuQEqsCSMTn)

{% hint style="warning" %}
Blheli\_S ESC only support Dshot300 on RPM filter.
{% endhint %}

If it show **E: 100%**, means Bi-dshot doesn't work. You should check setting again.

![](/files/-M3JpQIyFiO5RWZeG1Yj)


---

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