[{"id":"6791bad1501bb22a","type":"tab","label":"Flow 2","disabled":false,"info":"","env":[]},{"id":"338cd43473e9c97e","type":"LoRa Output","z":"6791bad1501bb22a","name":"send modbus command read register1 to 4","eui":"24E124445C195920","payloadType":"hex","payload":"0103000000044409","confirmed":true,"port":"126","x":690,"y":120,"wires":[]},{"id":"9286d28233ec9617","type":"inject","z":"6791bad1501bb22a","name":"inject every 300 seconds","props":[],"repeat":"","crontab":"","once":true,"onceDelay":"300","topic":"","x":330,"y":120,"wires":[["338cd43473e9c97e"]]},{"id":"fa5877e64e18a487","type":"LoRa Input","z":"6791bad1501bb22a","name":"","devEUI":"","extendedField":"","x":180,"y":220,"wires":[["22927f94ad9846da"]]},{"id":"22927f94ad9846da","type":"Device Filter","z":"6791bad1501bb22a","name":"","eui":"24E124445C195920","x":410,"y":220,"wires":[["dcdc9cc58b8da59a"]]},{"id":"dcdc9cc58b8da59a","type":"function","z":"6791bad1501bb22a","name":"Extracting values and combining","func":"// Function to combine four 16-bit registers into a single 64-bit value\nfunction combineRegisters(msg_payload_base64) {\n    // Step 1: Decode the Base64 payload to raw bytes\n    let payload_bytes = Buffer.from(msg_payload_base64, 'base64');\n\n    // Step 2: Convert the raw bytes to a hexadecimal string\n    let payload_hex = payload_bytes.toString('hex');\n\n    // Step 3: Extract the values of the four registers from the hexadecimal string\n    // Assuming the values are 16-bit and stored consecutively\n    let register1_hex = payload_hex.slice(6, 10);  // First 4 characters (2 bytes) for register 1\n    let register2_hex = payload_hex.slice(10, 14);  // Next 4 characters (2 bytes) for register 2\n    let register3_hex = payload_hex.slice(14, 18); // Next 4 characters (2 bytes) for register 3\n    let register4_hex = payload_hex.slice(18, 22);// Next 4 characters (2 bytes) for register 4\n\n    // Convert the hexadecimal values to integers\n    let register1_value = parseInt(register1_hex, 16);\n    let register2_value = parseInt(register2_hex, 16);\n    let register3_value = parseInt(register3_hex, 16);\n    let register4_value = parseInt(register4_hex, 16);\n\n    // Step 4: Combine the four 16-bit register values into a single 64-bit value\n    // JavaScript doesn't handle 64-bit integers natively, so we'll use BigInt\n    let combined_value = (BigInt(register1_value) << 48n) |\n        (BigInt(register2_value) << 32n) |\n        (BigInt(register3_value) << 16n) |\n        BigInt(register4_value);\n    // current byte order is ABCDEFGH\n    return { combined_value, payload_hex, register1_hex, register2_hex, register3_hex, register4_hex };\n}\n\n// Example usage\nlet msg_payload_base64 = msg.payload;  // Assuming msg.payload contains the Base64 encoded payload\nlet result = combineRegisters(msg_payload_base64);\n\n// Add the combined value, hex payload, and register hex values to the message\nmsg.combined_value = result.combined_value;\nmsg.payload_hex = result.payload_hex;\nmsg.register1_hex = result.register1_hex;\nmsg.register2_hex = result.register2_hex;\nmsg.register3_hex = result.register3_hex;\nmsg.register4_hex = result.register4_hex;\n\n// Set the payload to an object containing combined_value, payload_hex, and register hex values\nmsg.payload = {\n    combined_value: result.combined_value,\n    payload_hex: result.payload_hex,\n    register1_hex: result.register1_hex,\n    register2_hex: result.register2_hex,\n    register3_hex: result.register3_hex,\n    register4_hex: result.register4_hex\n};\n\nreturn msg;\n","outputs":1,"noerr":0,"initialize":"","finalize":"","libs":[],"x":710,"y":220,"wires":[["40d119dc08447a5a"]]},{"id":"40d119dc08447a5a","type":"debug","z":"6791bad1501bb22a","name":"debug 5","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":1000,"y":220,"wires":[]}]