JLog2.x also uses the multi-ESC HERKULES III and DJI NAZA-M as “ESC” for virtual sensors. Both still remained as a task after the initial release, – to transfer it in JLog3 S32. The re-implementation now began. The effort is unfortunately immensely since the structure of the data of a multicopter differs fundamentally from the otherwise usual. It requires a JLog in the JLog, so to speak, – in every respect: data evaluation, alarming, logging, JLog setup, and especially in the telemetry displays.
“JLog-NAZA” uses the spy “C2T” on the CANbus of the DJI system. This “sniffs” all the data from the CANbus, combining data obtained into meaningful output, e.g. to a tilt-compensated compass. C2T provides buffer management between the different data rates of the buses. – 1 mbps CAN and complex messages at NAZA’s end, – I²C 0.4 mbps, compressed message blocks from C2T to JLog2.x. I²C is JLog’s “data bus”, also called TWI (Two Wire Interface), “C2T” simply means “CANbus to TWI”. – C2T generates the heartbeat of a DJI OSD (OnScreen Display) to animate NAZA to send relevant data.
C2T contains an ARM 32bit microcontroller.
It is S32′s “side job” to entirely replace C2T in hardware and software. It also has a CANbus interface, port 6. Besides, it must of course also implement “JLog-NAZA” – and it needs its setup in the S32terminal.
It does now, – from S32 firmware version 1.20 and terminal version 188.8.131.52. The implementation is not yet completed, – supported telemetry is so far only JETI (jetibox, EX, EXbus) and HoTT (“EAM” + “GPS”, text). The logging uses 3 own OpenFormat records, so there is in the download an extra device description file for LogView2. As soon as the NAZA GPS receiver has a fix, 3 types of NMEA Records will appear on top in the log. A log file can feed both for viewing, LogView2 (in the future also DataExplorer) as well as Google Earth. For GE to recognize the file, the extension is not “.txt” but “.nmea”. The log viewer ignores records in NMEA format, GE ignores OpenFormat records. Each picks up its input from a log file.
The transfer JLog2-> JLog3 (S32) is now continued until all telemetry systems are supported for the display of NAZA data.
(The required connection harness will soon be available in the shops.)
Contrary to JLog(2.x)-NAZA, CVS16 is now also supported as an optional sensor.
The following picture proves: Programming can be even healthy by the minute. Two minutes “walking” to check the NMEA logging (-> Google Earth).
P.S. The firmware image was increased by 16%. Some will notice this when updating the S32 via the terminal, especially if its Windows is anyway one of the slow type on USB HID (Win10). – One death must be dying. The decision was made in favor of the USB device class “HID” (Human Interface Device) in order to avoid any trouble when installing a driver. Unfortunately, the transfer size is limited on HID, – 64 bytes on Full Speed USB. Due to the fact that the terminal (PC) and S32 are talking in a handshake (ping pong) per transfer, the time requirement adds up.