application: current: Added ChirpStack decoder

Author: fyziktom

applications/current/codec/cs-decoder.js

@@ -0,0 +1,179 @@
+var cursor = 0;
+var buffer;
+
+function decodeUplink(input) {
+    var bytes = input.bytes;
+    buffer = bytes;
+
+    var data = {};
+
+    var header = u16();
+
+    if ((header & 0x0001) !== 0) {
+        data.voltage_rest = u16();
+        data.voltage_load = u16();
+        data.current_load = u8();
+
+        if (data.voltage_rest === 0xffff) {
+            data.voltage_rest = null;
+        } else {
+            data.voltage_rest = data.voltage_rest / 1000;
+        }
+
+        if (data.voltage_load === 0xffff) {
+            data.voltage_load = null;
+        } else {
+            data.voltage_load = data.voltage_load / 1000;
+        }
+
+        if (data.current_load === 0xff) {
+            data.current_load = null;
+        }
+    }
+
+    if ((header & 0x0002) !== 0) {
+        data.orientation = u8();
+
+        if (data.orientation === 0xff) {
+            data.orientation = null;
+        }
+    }
+
+    if ((header & 0x0004) !== 0) {
+        data.therm_temperature = s16();
+
+        if (data.therm_temperature === 0x7fff) {
+            data.therm_temperature = null;
+        } else {
+            data.therm_temperature = data.therm_temperature / 100;
+        }
+    }
+
+    if ((header & 0x0008) !== 0) {
+        data.w1_thermometers = [];
+
+        var count = u8();
+
+        for (var i = 0; i < count; i++) {
+            var t = s16();
+
+            if (t === 0x7fff) {
+                t = null;
+            } else {
+                t = t / 100;
+            }
+
+            data.w1_thermometers.push(t);
+        }
+    }
+
+    if ((header & 0x0010) !== 0) {
+        data.backup = {}
+
+        data.backup.line_voltage = u16();
+        data.backup.battery_voltage = u16();
+        data.backup.backup_state = u8() !== 0 ? "connected" : "disconnected";
+
+        if (data.backup.line_voltage === 0x7fff) {
+            data.backup.line_voltage = null;
+        } else {
+            data.backup.line_voltage = data.backup.line_voltage / 1000;
+        }
+
+        if (data.backup.battery_voltage === 0x7fff) {
+            data.backup.battery_voltage = null;
+        } else {
+            data.backup.battery_voltage = data.backup.battery_voltage / 1000;
+        }
+    }
+
+    var analog_channels = [];
+
+    for (var i = 0; i < 4; i++) {
+        if ((header & (0x0020 << i)) !== 0) {
+            var channel = {};
+            channel.channel = i + 1;
+
+            var mean_avg = s32();
+            var rms_avg = s32();
+
+            channel.measurements = {};
+
+            if (mean_avg === 0x7fffffff) {
+                channel.measurements.mean_avg = null;
+            } else {
+                channel.measurements.mean_avg = mean_avg / 1000;
+            }
+
+            if (rms_avg === 0x7fffffff) {
+                channel.measurements.rms_avg = null;
+            } else {
+                channel.measurements.rms_avg = rms_avg / 1000;
+            }
+
+            analog_channels.push(channel);
+        }
+    }
+
+    if (analog_channels.length > 0) {
+        data.analog_channels = analog_channels;
+    }
+
+    return {
+        data: data
+    };
+}
+
+function s8() {
+    var value = buffer.slice(cursor);
+    value = value[0];
+    if ((value & (1 << 7)) > 0) {
+        value = (~value & 0xff) + 1;
+        value = -value;
+    }
+    cursor = cursor + 1;
+    return value;
+}
+
+function u8() {
+    var value = buffer.slice(cursor);
+    value = value[0];
+    cursor = cursor + 1;
+    return value;
+}
+
+function s16() {
+    var value = buffer.slice(cursor);
+    value = value[0] | value[1] << 8;
+    if ((value & (1 << 15)) > 0) {
+        value = (~value & 0xffff) + 1;
+        value = -value;
+    }
+    cursor = cursor + 2;
+    return value;
+}
+
+function u16() {
+    var value = buffer.slice(cursor);
+    value = value[0] | value[1] << 8;
+    cursor = cursor + 2;
+    return value;
+}
+
+function u32() {
+    var value = buffer.slice(cursor);
+    value = value[0] | value[1] << 8 | value[2] << 16 | value[3] << 24;
+    cursor = cursor + 4;
+    return value;
+}
+
+function s32() {
+    var value = buffer.slice(cursor);
+    value = value[0] | value[1] << 8 | value[2] << 16 | value[3] << 24;
+    if ((value & (1 << 31)) > 0) {
+        value = (~value & 0xffffffff) + 1;
+        value = -value;
+    }
+    cursor = cursor + 4;
+    return value;
+}