Unity and delay

[Champang]

I tested a BNO085, 9-axis IMU to send via WiFi with a Lolin D32 on signalK on a Raspberry 3+. Problems

• in angle units. OpenCPN does not read radians, I have to specify "navigation.headingCompass","units","deg".
• the period between two acquisitions with a value less than 500 milliseconds is versatile. ` /*
  • Sensesp : https://github.com/SignalK/SensESP
  • send data to
  • signalk : https://github.com/SignalK/signalk-server
  • BNO085 IMU 9 axes exemple : https://www.adafruit.com/product/4754
  • This example outputs Heading, Roll, Pitch every 500 ms
  • Use Visual Code Studio and Platformio
  • see PlatformIO Project Configuration File at the bottom of the script. */

// Sensor-specific #includes:

include

include

include

include // Device I2C = 0x4B if DI = Vcc

// Boilerplate #includes:

include "sensesp/sensors/sensor.h"

include "sensesp/signalk/signalk_output.h"

include "sensesp_app.h"

include "sensesp_app_builder.h"

define I2C_BUFFER_LENGTH 32

//#define I2C_SCL 22 //#define I2C_SDA 21

using namespace sensesp;

reactesp::ReactESP app; BNO080 myIMU;

float degree = 2; float pitch = 2; float roll = 1; float yaw = 1;

float yaw_callback() { if (myIMU.dataAvailable() == true) {
yaw = (myIMU.getYaw()) * 180.0 / PI; // Convert yaw / navigation.heading to degrees if (yaw < 0) yaw += 360.0; degree = 360 - yaw; if (degree < 0) degree += 360.0; } int temp = degree; yaw = temp;

//yaw = (myIMU.getYaw());

return (yaw); }

float pitch_callback() { if (myIMU.dataAvailable() == true) { pitch = (myIMU.getPitch() * 180.0 / PI); // Convert pitch to degrees } int temp = pitch; pitch = temp; return (pitch); }

float roll_callback() { if (myIMU.dataAvailable() == true) { roll = (myIMU.getRoll() * 180.0 / PI); // Convert roll to degrees } int temp = roll; roll = temp; return (roll); }

void setup() { // Some initialization boilerplate when in debug mode...

ifndef SERIAL_DEBUG_DISABLED

SetupSerialDebug(115200);

endif

Wire.begin(21, 22); Wire.setClock(400000); delay(1000); myIMU.begin(); myIMU.enableRotationVector(30);

// Construct the global SensESPApp() object SensESPAppBuilder builder;

sensesp_app = (&builder) // Set a custom hostname for the app. ->set_hostname("YOUR_HOSTNAME") // Optionally, hard-code the WiFi and Signal K server // settings. This is normally not needed. ->set_wifi("SSID", "PASSWORD") ->set_sk_server("IP_SignalK_server", 3000) ->get_app();

// Create the ConstantSensor object all 500 millisecondes auto yaw = new RepeatSensor(500, yaw_callback); auto pitch = new RepeatSensor(500, pitch_callback); auto* roll = new RepeatSensor(500, roll_callback);

// create and connect the output object yaw->connect_to(new SKOutputFloat("navigation.headingCompass","units","deg")); pitch->connect_to(new SKOutputFloat("navigation.attitudepitch","units","deg")); roll->connect_to(new SKOutputFloat("navigation.attituderoll","units","deg"));

// Start the SensESP application running sensesp_app->start(); }

void loop() { app.tick(); }

/* ; PlatformIO Project Configuration File : Lolin D32 ; Advanced options: extra scripting ; ; Please visit documentation for the other options and examples ; https://docs.platformio.org/page/projectconf.html

[env:lolin_d32] platform = espressif32 board = lolin_d32 framework = arduino board_build.mcu = esp32 board_build.f_cpu = 240000000L board_build.flash_size = 4MB board_build.flash_mode = dio board_build.partitions = min_spiffs.csv lib_deps = ;adafruit/Adafruit Unified Sensor ;sparkfun/SparkFun BNO080 Cortex Based IMU ;signalk/SensESP adafruit/Adafruit Unified Sensor @ ^1.1.14 sparkfun/SparkFun BNO080 Cortex Based IMU @ ^1.1.12 signalk/SensESP@^2.7.2 ;upload_port = /dev/ttyUSB0 ;upload_flags = ; --upload-reset */ `

[mairas]

in angle units. OpenCPN does not read radians, I have to specify "navigation.headingCompass","units","deg".

This is wrong. Signal K values are always in SI units. Angular values are always in radians. If OpenCPN supports Signal K, it does support angles in radians.

the period between two acquisitions with a value less than 500 milliseconds is versatile.

Could you rephrase? I don't quite understand.

[Champang]

Hello, you confirm the weakness of OpenCPN in unit management. Concerning the latency of data exchanges, my objective is to be able to recover certain data on an Esp8266 to display them on a Nokia 5110. I don't know how to directly query Signalk-server to retrieve this data, so I use Mosquitto. When I query signalk-server on http://10.10.10.1:3000/admin/#/databrowser, I notice that if I put a value less than 500ms in sending data, the display is less responsive following the displacement of BNO085. // Create the ConstantSensor object all 500 millisecondes auto* yaw = new RepeatSensor<float>(500, yaw_callback); auto* pitch = new RepeatSensor<float>(500, pitch_callback); auto* roll = new RepeatSensor<float>(500, roll_callback);

[mairas]

Repeat reactions can run tens of thousands of times per second without any issues. If you're having latency issues, it's likely that your accelerometer library functions are blocking for a long time.

I'm closing this issue because these problems do not seem to be related to SensESP itself.