Proshot is an ESC protocol that encodes DShot using PWM pulses. While it offers some theoretical advantages over DShot, whether it makes a noticeable difference—and whether those benefits outweigh its downsides—is still a matter of debate.
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Benefits and Downsides
Proshot is an ESC protocol protocol with features similar to DShot, such as the same throttle resolution, frame structure, and CRC. However, it comes with some unique benefits:
Benefits:
- Reduced CPU Utilization
Proshot sends only 4 pulses per signal instead of DShot’s 16, decreasing CPU load. - Easier Compatibility with Microcontrollers
Proshot’s design is simpler for microcontrollers to process without requiring DMA, broadening compatibility with various MCUs. - Noise Reduction
Its wider pulses allow the use of filtering capacitors on the signal line, which can reduce noise. - Higher Update Rate
Proshot enables a higher update rate than DShot due to its shorter signal width. However, achieving very high rates may require removing the filtering capacitor, potentially compromising signal integrity.
Possible Downsides and Questions:
- Noise Susceptibility
Proshot’s PWM pulses could be more prone to noise interference compared to DShot’s simpler pulse states. Additional filtering capacitors may help mitigate this. - Suitability for High-Speed Operations
At very high update rates, Proshot might struggle without filtering capacitors, which could result in signal instability. - Performance Gains
It’s unclear whether a faster ESC protocol like Proshot would significantly enhance FPV drone performance. DShot, for example, has already achieved faster rates (e.g., DShot3600), raising the question of whether Proshot is necessary.
How Does Proshot Work?
Proshot generalizes the DShot protocol by encoding the 16-bit DShot signal into 4 PWM pulses, each carrying 4 bits of data. This reduces the overall packet length, enabling faster transmission rates.
Some argue that Proshot is more analog than digital in nature, because it uses PWM pulses. However, the Proshot creator clarified that the signal is technically digital due to its finite number of states (16 states to represent hexadecimal digits), similar to DShot’s binary states. Like DShot, Proshot does not require ESC calibration which is recommended for analog ESC protocol.
At the time of publishing, Proshot still remains a concept awaiting wider adoption. Its success depends heavily on developers like those behind BLHeli and KISS implementing it in their firmware. This hobby is filled with innovative minds, so the potential for Proshot remains intriguing.
Watch the Author’s Explanation on Proshot:
Update (Aug 2017) – Proshot1000 Added to Betaflight
Proshot1000 has been introduced in Betaflight with the BF3.2 RC3 update. However, no ESCs currently support Proshot1000, awaiting further development. The “1000” refers to its speed, which is faster than DShot600 but slower than DShot1200.
Update (Dec 2019) – BLHeli_32 Dropping Proshot Support
According to BLHeli developers, future revisions of BLHeli_32 will no longer support Proshot due to the following reasons:
- Limited Adoption
Proshot is not widely used and can be replaced by DShot. - Timing Sensitivity
Proshot signaling is more timing-sensitive and less robust compared to DShot. - Efficiency
Removing Proshot reduces firmware complexity and saves flash space in BLHeli_32.
Proshot is also expected to be removed from Betaflight as DShot remains the Betaflight team’s recommended protocol.
Final Thoughts
Proshot introduced interesting ideas to the world of ESC protocols, such as reduced CPU utilization and noise filtering. However, limited adoption and technical challenges have kept it from becoming a viable alternative to DShot. With support being phased out in popular platforms like BLHeli_32 and Betaflight, Proshot may not see widespread usage.
For now, DShot continues to dominate as the go-to ESC protocol for FPV drones, ensuring reliability and performance for all levels of pilots.
6 comments
Shouldn’t this have a big effect on the VTX feed in terms of noise introduction? Proshot1000 should have a cleaner feed from these findings?
Hey Felix, I do not think youn exactly accurate. Point being, proshot speed is needed, such as was dshot1200. I have experienced a big difference to me between dshot600 and dshot1200, it was not my choice to have dshot1200 removed, and I do not agree with betaflight in the reason to remove it, I do not agree there was not that much difference between the 2 protocols, there for sure was, and I noticed it. Dshot600 is fine, not for me, I find it a little to sluggish for my beefier drones, dshot600 is fine for stuff like tinyhawk, and other small little ladies, but when I get to my betafpv 85x and my cinepro 4k, dshot 1200 is what I want, now what my betafpv 85x I got it when dshot was still out and I love it, when I got the GepRC cinepro 4k it had 4.1.1 and I had 2 choices dshot600, and proshot. Neither is where I want to be, but proshot is seriously better than dshot600. Yes maybe we can go even faster with dshot, and should BetaFlight remove their heads from that dark hole and see the light maybe they will bring back dshot1200 or make an even faster dshot, till that day, we are left with proshot1000, obviously the choice and replacment for dshot1200.
Digital does not exist in nature. It is a man made concept that we do our best to implement using analog methods ;-)
Ingenious way to allow antique Blackout v2.0 quads running white Naze boards to keep running with the youngin’s ;)
Hi,
as written in the RCG thread, i see absolutly no reason to support it with the KISS ESC’s as it has no adventages over Dshot if the ESC has a DMA and a HW input filter. it just is a bit weaker from the safety side. it can pass filter capacitors better, but the ST MCU’s have adjustable input noise filters that work eaven better then a simple RC filter. and they can be adjusted to work with every needed frequency.
from the speed side. we are at so high speeds ATM. where i dont think it makes sense to secrifice safty for more speed.. and as written, with dshot are also much higher speeds possible.
so i would say, it can be a good thing for older MCU’s with no internal filter and DMA, but it makes no sense if used with modern once.
regards
Felix
Thanks for the great insight Felix.