SBUS Baud Fast (RC2 + O3 + G2)
3161 4 2023-5-9
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Guy Aroshas
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Flight distance : 604426 ft
Israel
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Does anyone have any insights on using the DJI Remote Controller 2, with O3, and Goggles 2?
There is an option to choose Normal SBUS or SBUS Baud Fast.
Upon inspecting the Betaflight blackbox logs of RC_Command between the two, I see the same 200Hz 5ms link speed.
What is the point then of selecting SBUS fast. What is the difference between them?

Is there any official information about Normal SBUS and SBUS Baud Fast?

2023-5-9
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RiChaDo
Second Officer
Flight distance : 3085075 ft
Netherlands
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same here.. I want to know
2023-5-10
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Guy Aroshas
lvl.2
Flight distance : 604426 ft
Israel
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I’ve looked at some more info, and it seems to the difference is only the BAUD rate between the O3 and FC. There is no change in link speed between the remote and O3, which stays 200Hz on both. SBUS fast is 200000 baud instead of 100000 on the normal SBUS.
Is we calculate this, each SBUS packet is built of 25 bytes, and the protocol uses parity and 2 stop bits.
So Start bit + Data byte + Parity Bit + 2 Stop bit = 12 bits
Multiply that by 25, and you get 300 bits per packet.
If we divide 100000 by 300 we get the ability of the Normal SBUS to transfer 333 packets per second, which is more than enough for the 200Hz link speed.
Taking all that into acoount, I can only assume that SBUS Fast could just make things worse in this scenario, because the higher the BAUD rate, the more it is sensutive to noise.

DJI, please give us info to confirm the above or explain else.
2023-5-10
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FPV Juice
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Flight distance : 799701 ft
Germany
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Guy Aroshas Posted at 5-10 02:38
I’ve looked at some more info, and it seems to the difference is only the BAUD rate between the O3 and FC. There is no change in link speed between the remote and O3, which stays 200Hz on both. SBUS fast is 200000 baud instead of 100000 on the normal SBUS.
Is we calculate this, each SBUS packet is built of 25 bytes, and the protocol uses parity and 2 stop bits.
So Start bit + Data byte + Parity Bit + 2 Stop bit = 12 bits
Could this have something to do with the failsafe situation? Sbus normal = more stable link?

https://forum.dji.com/forum.php?mod=viewthread&tid=288595&pbc=BCQ9HQ1u&pid=105307&pm=custom&ptid=13199&page=5
2023-8-17
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Guy Aroshas
lvl.2
Flight distance : 604426 ft
Israel
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FPV Juice Posted at 8-17 07:51
Could this have something to do with the failsafe situation? Sbus normal = more stable link?

https://forum.dji.com/forum.php?mod=viewthread&tid=288595&pbc=BCQ9HQ1u&pid=105307&pm=custom&ptid=13199&page=5

In my experience, after a lot of experimentation, it makes no difference. Also doesn’t help the failsafe issue.
2023-8-17
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