`packet_device` is a Node.js library for secure, packetized communication with microcontrollers (Arduino, ESP32, etc.) running the [Packet Device Arduino library](https://github.com/Pallob-Gain/packet_device).
npm install packet_devicepacket_device is a Node.js library for secure, packetized communication with microcontrollers (Arduino, ESP32, etc.) running the Packet Device Arduino library.
It uses a simple, event-driven architecture to send and receive structured binary data over serial, with CRC-16 validation.
---
- Communicate with Arduino/ESP32 over serial using the Packet Device protocol
- Send/receive typed structures (int, float, arrays, etc.)
- CRC-16 (CCITT-FALSE) data integrity
- Event-based data reception
- Works with any device implementing the Arduino Packet Device library
---
``bash`
npm install packet_device
This will also install the serialport dependency.
---
Install and flash the Packet Device Arduino library to your board.
Example Arduino sketch:
`cpp
#include "Packet_Device.h"
#include "BluetoothSerial.h"
#define MAX_COMMAND_LEN 128
typedef DevicePacket
PacketProtocol* device_packet = nullptr;
TaskHandle_t systemReceivingTask = nullptr;
#define SENSOR_NUMBERS 5
float sensor_data[SENSOR_NUMBERS] = { 10.0, 20.0, 30.0, 40.0, 50.0 };
// Data transfer definition between DSP and HOST
struct LockInInfo {
float amplitude;
float phase;
};
// Callback: Update lock-in info
void updateLockInfoX(LockInInfo* info) {
device_packet->restOut("amplitude", info->amplitude);
}
// Callback: Check version
void checkVersion() {
device_packet->restOutStr("version", "Packet Device");
}
// Data receiving thread
void systemReceivingProcess(void* parameter) {
while (true) {
// Read incoming commands
device_packet->readSerialCommand();
vTaskDelay(pdMS_TO_TICKS(20)); // 20 ms delay
}
// If loop breaks, clean up task
vTaskDelete(nullptr);
}
void setup() {
Serial.begin(115200);
// Create PacketProtocol object with delimiters
device_packet = new PacketProtocol(&Serial, { '\r', '\n' });
// Register command callbacks
device_packet->onReceive("VNR", checkVersion);
device_packet->onReceive
// Create data processing thread
xTaskCreatePinnedToCore(
systemReceivingProcess, // Task function
"recv", // Task name
10000, // Stack size in bytes
nullptr, // Task input parameter
2, // Priority
&systemReceivingTask, // Task handle
0 // Core ID
);
}
void loop() {
device_packet->processingQueueCommands();
device_packet->restArrayOut
delay(500);
}
`
---
`js
const { PacketDevice, Struct } = require('packet_device');
const { SerialPort } = require('serialport');
const PORT = 'COM3';
const BAUDRATE = 115200;
// Define a struct type
const lockInInfo = Struct.makeType({
amplitude: Struct.type.float,
phase: Struct.type.float
});
const packet_device = new PacketDevice('\r\n');
packet_device.onData((err, data) => {
if (err) return console.error('Data error:', err);
try {
console.log('Received ->', PacketDevice.dataParse(data));
} catch (err) {
console.error('Data parse error:', err);
}
});
(async () => {
let ports = await SerialPort.list();
let portInfo = ports.find(p => p.path === PORT);
if (!portInfo) return console.error(Port ${PORT} not found);
const serialport = new SerialPort({ path: PORT, baudRate: BAUDRATE });
serialport.on('open', async () => {
packet_device.open(serialport);
let data = new Struct(lockInInfo);
data.setJson({ amplitude: 5.0, phase: 0.5 });
packet_device.println("VNR");
let version = await packet_device.waitUntillFound(['version'], 2000);
console.log('version:', version);
setInterval(() => {
packet_device.writePacket("ULX", data);
}, 1000);
});
serialport.on('close', () => {
packet_device.close();
console.log('Device disconnected.');
});
})();
`
---
`
+----------------------------+
| Node.js Application |
| (commands, data handling) |
+----------------------------+
| packet_device Protocol |
| (framing, CRC, parsing) |
+----------------------------+
| Serial Transport |
| (via serialport) |
+----------------------------+
---
| Method | Description |
|--------|-------------|
| new PacketDevice(delimiter) | Create a new PacketDevice instance with a delimiter (e.g., \r\n). |onData(callback)
| | Receive incoming raw or parsed data. |open(serialPort)
| | Bind to a SerialPort instance. |close()
| | Close the connection. |writePacket(cmd, data)
| | Send a structured packet. |println(text)
| | Send a text command without packet framing. |waitUntillFound(keys, timeout)` | Await a response containing one of the given keys. |
|
---
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