Hi guys,
What exactly is the structure of the SBUS?
My best source so far is this one:
https://developer.mbed.org/users/Digixx/notebook/futaba-s-bus-controlled-by-mbed/
In one line it says each channel has 11 bits, but in the other lines it says 12 (1 start + 8 data + 1 parity + 2 stops).
Could you please help? Thank you
You usually can't go wrong by adding extra stop bits.
Thank you KeithRB. Do you mean, let's say the RX expects 12 bits packet and the TX sends 11 bits packet, it will just automatically know one stop bit is missing and then just work fine?
No, I am saying that if you are unsure, it is better to send 2 stop bits to be safe. If 2 are required and you only send one, there could be problems.
In one line it says each channel has 11 bits, but in the other lines it says 12 (1 start + 8 data + 1 parity + 2 stops).
If this is a uart-like protocol, you use the start bit to tell your code (or hardware) to start receiving data, shift the 8 data bits into a saved location, check (or ignore) the parity bit without saving it, and confirm that A stop bit happens after tha parity bit. So you're really NOT reading "12 bits"; some of the bits are "framing" but not interesting to save. Extra stop bits are identical to "idle time" in between characters, and allow re-synchronization. (After you see the start bit transition, you read bits at set time intervals until after the parity bit. Then you essentially reset and wait for the next start bit. This is how some uarts meaningfully support 1.5 stop bits...
(Transmitting is slightly different.)
This is for HobbyKing Corona Sbus 4ch. Rx decorder program.
You can monitor Sbus all data by Arduino Uno/Nano/mini with 2Mbps UART Arduino IDE monitor.
Takao
Some info on SBUS here SparkFun According to Pete #47 - Drones and the Futaba Serial bus - YouTube