FPV Protocols: PWM, CPPM, CCPM, PPM, S.Bus, I.Bus, S.Port…
Fleeting- External reference: https://www.jouav.com/blog/electronic-speed-controller-esc.html
- External reference: https://oscarliang.com/rc-protocols/
- External reference: https://frskytaranis.forumactif.org/t5119-ne-comprend-pas-la-difference
- External reference: https://www.clubamcl.fr/techniques/la-technologie-futaba-s-bus/
- External reference: https://drones.stackexchange.com/questions/177/what-is-the-advantage-of-sbus-over-ibus
- External reference: https://frskytaranis.forumactif.org/t4426-pwm-cppm-ccpm-ppm-s-bus-s-port-kesako
PWM, CPPM, CCPM, PPM, S.Bus, S.Port…. Késako ??
An ESC ->
— https://www.jouav.com/blog/electronic-speed-controller-esc.html
Pulse Position Modulation
— https://frskytaranis.forumactif.org/t4426-pwm-cppm-ccpm-ppm-s-bus-s-port-kesako
transmet 8 voies (voir 12 dans certains cas) avec un seul signal (= un seul fil). Ce protocole est assez lent.
— https://frskytaranis.forumactif.org/t4426-pwm-cppm-ccpm-ppm-s-bus-s-port-kesako
Quand vous avez le choix, privilégiez toujours le S.Bus.
— https://frskytaranis.forumactif.org/t4426-pwm-cppm-ccpm-ppm-s-bus-s-port-kesako
S.Bus (Serial Bus):
— https://frskytaranis.forumactif.org/t4426-pwm-cppm-ccpm-ppm-s-bus-s-port-kesako
lorsque vous avez le choix, privilégiez toujours le S.Bus
— https://frskytaranis.forumactif.org/t4426-pwm-cppm-ccpm-ppm-s-bus-s-port-kesako
connexion UART avec un baud composé de 1 start bit + 8 data bit + 1 even parity bit + 2 stop bit (8E2).Le baudrate est de 100 000 bit/sLe bit de poids fort (MSB) est envoyé en 1er. La logique est inversé (état haut = ‘0’, état bas = ‘1’).
— https://frskytaranis.forumactif.org/t4426-pwm-cppm-ccpm-ppm-s-bus-s-port-kesako
SBUS and IBUS are both digital protocols and for a digital protocol, you define two voltage values to represent an active state and one inactive state. This is done for every digital protocol.
— https://drones.stackexchange.com/questions/177/what-is-the-advantage-of-sbus-over-ibus
You get similar performance from SBUS and IBUS since both are a serial protocol with comparable frame times.
— https://drones.stackexchange.com/questions/177/what-is-the-advantage-of-sbus-over-ibus
inversion is due to the electrical design of the receiver. Usually, you will find an uninverted pad on the receiver too
— https://drones.stackexchange.com/questions/177/what-is-the-advantage-of-sbus-over-ibus
Tous les modélistes utilisent aujourd’hui la technologie PWM « Pulse Width Modulation » ou « Modulation de Larges Impulsions ».
— https://www.clubamcl.fr/techniques/la-technologie-futaba-s-bus/
technologie PWM reste sensible aux perturbations électriques.
— https://www.clubamcl.fr/techniques/la-technologie-futaba-s-bus/
Passer en numérique
— https://www.clubamcl.fr/techniques/la-technologie-futaba-s-bus/
Remède : la technologie S-Bus
— https://www.clubamcl.fr/techniques/la-technologie-futaba-s-bus/
ibus est “similaire” en principe, mais incompatible donc il n’est pas possible d’utiliser les mêmes accessoires qu’en SBUS, et comme il n’existe pas d’accessoires similaires en ibus… bah en gros non
— https://frskytaranis.forumactif.org/t5119-ne-comprend-pas-la-difference
SBUS existe depuis 10 ans, plein de monde a fait des accessoires qui le supportent et c’est donc répandu et largement utilisé… l’ibus est un truc propriétaire flysky et en gros tout le monde s’en fout donc à part pour les 2-3 contrôleurs de multicoptères qui le supportent il ne sert à rien.
— https://frskytaranis.forumactif.org/t5119-ne-comprend-pas-la-difference
- TX Protocols – communication between radio transmitter (TX) and radio receiver (RX)
- RX Protocols – communication between radio receiver (RX) and flight controller (FC)
- ESC Protocols – communication between FC and ESC
RX protocols are universal and used in receivers from different manufactures, but some can be exclusive to certain brands.
PWM (universal) PPM or CPPM (universal)
SBUS (Futaba, Frsky) IBUS (Flysky)
serial protocol is a digital loss-less protocol that uses only 3 wires (signal, power, ground) for multiple channels.
SBUS Aka S.BUS or Serial BUS, is commonly used by Futaba and FrSky. It supports up to 16 channels using only one signal wire. SBUS signal should be connected to the RX pin of an UART.
ESC stands for Electronic Speed Controller. It is an electronic circuit that connects the motor, the battery, and the flight controller, whose primary purpose is to change the speed and direction of the drone
— https://www.jouav.com/blog/electronic-speed-controller-esc.html
pilot transmits a signal from a radio transmitter, which is received by a radio receiver fixed to the UAV, and then further sends that signal to the flight controller board, which generates an appropriate signal and forwards it to the BEC/ESC, which speeds up the motor depending on the strength of that signal.
— https://www.jouav.com/blog/electronic-speed-controller-esc.html
Communication between the FC and ESC’s is wired as well. ESC protocols are basically the flight controller telling the ESC how fast they should drive the motors.