JESC Firmware

JESC: Betaflight RPM Filter on BLHeli_S Hardware

Quadcopter flight performance is greatly improved by reducing motor noise in the gyro signal and by removing filter delay. Unfortunately these goals used to oppose each other: filter out more motor noise and you will get more delay.

Not any more! RPM Filtering allows Betaflight to place very narrow notch filters on the harmonics of your motors with surgical precision. Notch filters have infinite noise suppression at their center. This allows the Rpm Filter to completely remove motor noise from your FC with much less delay than we're used to. Learn more.

The JESC firmware is based on the open source project BLHeli_S and also open source. To enable dshot rpm telemetry you need to license the optional Telemetry Service. Each ESC requires one license. Purchase 4 licenses for a 4 in 1, a single one if you need to replace one single ESC. Or splurge on the 20 license discount package to equip multiple 4 in 1's.

Before ordering read the Install Instructions to verify that your setup is supported and to understand the install process. Please consult the FAQ if you have questions!

JESC Overview

Quadcopter flight performance is greatly improved by reducing motor noise in the gyro signal and by removing filter delay. Unfortunately these goals used to oppose each other: filter out more motor noise and you will get more delay.

Not any more! RPM Filtering allows Betaflight to place very narrow notch filters on the harmonics of your motors with surgical precision. Notch filters have infinite noise suppression at their center. This allows the Rpm Filter to completely remove motor noise from your FC with much less delay than we're used to.

The results are smoother and colder motors - even with bent props - and better pid loop performance due to the much reduced filter delay. The ESCs make this possible by sending the current speed of each motor at full pid loop speed to the FC where it's used to tune the filters.

Formerly this worked only with BLHeli32 ESCs - and so far only a beta is available. JESC enables BLHeli_S ESCs to fully support dshot signal line rpm telemetry at up to dshot 600 and 8k pid frequency. No additional wiring required.

Requires an efm8bb21 based BLHeli_S ESC. You can recognize them by their name tag displayed in BLHeli Configurator: if it contains an H in the middle like F-H-30 it's supported.

The JESC firmware is based on the open source project BLHeli_S and also open source. To enable dshot rpm telemetry you need to license the optional Telemetry Service. Each ESC requires one license. Purchase 4 licenses for a 4 in 1, a single one if you need to replace one single ESC. Or splurge on the 20 license discount package to equip multiple 4 in 1's.

Additional benefits:

• Startup beeps indicate whether dshot telemetry is working between FC and ESC.
• Only supports dshot - not legacy protocols. This reduces the risk of motor spin-ups due to protocol detection issues and makes the firmware smaller and faster.
• Completely configurable using the cross platform JESC-Configurator

More information:

Have questions? Check out our FAQ or visit the JESC rcgroups thread.
Ready to purchase? Checkout out Install Instructions to learn the process.

 

JESC Install Instructions

JESC is currently in early access and works with Betaflight 4.1 RC3 and up. Please be extra careful and follow these instructions to the letter! Make sure your internet connection is working. Have questions? Check out our FAQ or visit the JESC rcgroups thread.

• Check whether your ESC supports JESC:
  Start the BLHeli Configurator and check the name of the ESC. It's of the form A-H-30. If the middle letter is an H the ESC is supported.
   
• Check whether your FC is supports bidirectional dshot. All STM32F4 and STM32F7 based FCs do.
   
• Download and install the latest betaflight hex with JESC support for your FC. JESC support is now in the latest nightly builds. Install nightly builds using BetaFlight Configurator in "Expert Mode" showing "unstable releases":
  
  
   
• Download and install the latest JESC Configurator here.
   
• Visit https://jflight.net, set up an account and purchase the required Telemetry licenses for your esc.
   
• Start JESC Configurator, and use the "License All" button to connect your licenses to your esc.
   
• Flash the latest JESC firmware by pressing "Flash All" and follow instructions.
   
• Flash the latest Telemetry firmware by pressing "Flash All Telemetry" and follow instructions.
   
• If you have any problems during licensing / flashing use the "Save Debug Log" button to produce a log to share with us
   
• Now follow the BetaFlight RPM Filter Instructions.

 

JESC FAQ

• Can licenses be transferred from one ESC to another, e.g. if I lose a quad or if an ESC breaks?
  Answer: Unfortunately we have no way to detect whether an ESC is still in use or not. Therefore we have decided to make the licenses very inexpensive instead, but to require a license for each new ESC. With the 20 license bundle which has a discount of 20% over the 4 license bundle the license costs for a 4:1 esc are $4 - about 1/3rd of a motor. That should put the license costs in perspective.
   
• Do I have to get a new license for each update?
  Answer: No, maintenance updates are free for life.
   
• How do I download the firmware?
  Answer: Please follow these instructions to license and install the product.
   
• Which ESCs are supported by JESC?
  Answer: JESC supports all BLHeli_S ESCs that use an efm8bb21 processor. You can recognize them by their name tag displayed in BLHeli Configurator: if it contains an H in the middle like F-H-30 it's supported.
   
• Which ESC protocols are supported?
  Answer: JESC supports DSHOT300 and DSHOT600 with rpm telemetry. Using DSHOT600 and an F7 flight controller 8k/8k is possible.
   
• Is JESC open or closed source?
  Answer: JESC is an open source project located here. It's derived from BLHeli_S and as such licensed under the GPL3. The Telemetry service is a optional closed source commercial product available at jflight.net which sends rpm telemetry back to the FC. Both firmwares can be installed using the also GPL3 licensed jesc-configurator.
   
• Does JESC run on BLHeli32 hardware?
  Answer: JESC currently runs only on ESCs using the efm8bb21 cpu. BLHeli32 supports rpm telemetry out of the box so you can get the full advantage of rpm filtering and dynamic idle with BLHeli32 as well.