Some time ago a lot of people consulting me how to sbus signal through 4G module, DTU transmission or data transmission, remote control. Their application is remote consumer robots, drones shipping, underwater robots and other projects.
Before answering this question we first look at sbus agreement.
SUBS is a purely digital control protocol standard comprises a servo signal sbus channel 18, can be expressed in the servo flux 0-2048. What is the steering gear flux, it is the work of the PWM servo signal, a pulse width of the PWM signal is generally used to represent us. Normal servo PWM signal range is between 1100us-1900us, 400us-1900us. There 500us-2500us, but relatively small. The basic drone mostly the first two. Our sbus protocol that is a digital signal PWM channel 18 is first compression-encoded packaging, and then sent out through the serial protocol type (abnormal oh UART) is. Our standard single-chip computer and other UART devices can not be directly read information sbus, the level required by the plastic can be read smoothly after baud rate adjustment.
SBUS baud rate comparison wonderful, 100k, 2 stop bits, even parity, the frame rate 7-15ms. This is not our usual baud rates: 4800,9600,38400,57600,115200 and so on. And 2 stop bits, many low-end microcontroller is not supported. This requires us to complete the normal ordinary serial received sbus on the need to sbus communication protocols make the necessary changes, first of all is to 100k baud rate into the normal baud rate, stop bits into the 2 1 stop bit, if that is too fast, then the frame rate, frame rate also need to come down.
Here everyone should know how you can do it. The principle is to turn into a standard protocol sbus through dtu emission, when data is received DTU, translated sbus. Equivalent sbus pass through.
1: transmitting end
Remote Control - "receiver (SBus output) -" SBus transfer 232- "digital transmission DTU
2: a receiving end
Data transmission DTU- "232 turn sbus-" sbus turn PWM- "servo.
Here's a list of configuration:
Remote control receiver, turn SBus module 232. Digital transmission DTU, 232 rpm sbus, sbus turn PWM
This is a closed loop of.
Interested to be a treasure to collect it. That is assembled about the problem. Here is a video,
