STM32 : 1, ESP32 : 0

Since Friday, I’ve been working on DShot generation with Xavier. As explained in his last post , we wanted to use only an ESP32 on the bottom PCB. 

First try of DShot with an ESP32

So last Friday we tried generating DShot with an ESP32 DevkitC and starting our motor with it.

After familiarising ourselves with the ESP API reference, we managed to generate a DShot signal on the SPI bus of the ESP32 using DMA. The idea is to send a DShot bit as an 8-bit SPI frame with the first 3 bits high to send a 0 and the 6 first bits high to send a 1, as explained in this post.… Read more

Taking our new ESCs for a spin

Today we received the AIKON 45A SEFM ESCs we ordered a while ago. Actually that’s a lie: these ESC were received before today, but no one told us until Alexis recalled seeing them when we told him we were waiting for them and pulled them from the top shelf of the cabinet in the back of the classroom. We’ll let it slide, whoever it was, but just this once.

Upon hearing this, Sibille and I immediately decided to put aside for the time being our previous attempts to reflash our most recent motor’s built-in ESC and instead use these new ESCs (which come flashed with BLHeli_S and support DShot out of the box) to control our other motor, the Turnigy Multistar 4225.… Read more

Motor Update

Today, I tried to reflash the built-in ESC of our new motor, EP4108.It runs BLHeli firmware, and we would like to update it in order talk to the ESC via a relatively new protocol, DShot, instead of the age-old PWM control. Short story long, I didn’t manage to do it.

Still, here’s what I tried.

As mentioned in this post, the motor has a 6-pin “flashing port” – except there is no provided connectors and absolutely no instruction on how to reflash the ESC. In fact, we don’t even know what ESC it is. All we know is that it runs some version of the BLHeli open source firmware.… Read more

A few bits about motors and ESCs

Hello,

Last Friday we received new motors : the EP4108 320KV with built-in ESC.

We’re particularly interested in those because they have a reflashable integrated BLHeli ESC. It turns out that, starting with BLHeli_S v16.5, which is an open source ESC firmware, a new protocol is supported to replace the old PWM control method : DShot. It’s a serial protocol where speed information is encoded in 16-bit frames, instead of analogically in the duty cycle of a PWM signal.

There are three generations of BLHeli firwmare : BLHeli, BLHeli_S, and BLHeli32 (wich is no longer open source), each with several versions.… Read more