Struct EegPacket 

pub struct EegPacket {
    pub timestamp: f64,
    pub event_id: u8,
    pub counter: u8,
    pub ref_value: f32,
    pub drl: f32,
    pub channels: Vec<f32>,
    pub feature_status: u8,
    pub checksum_valid: bool,
}

A parsed EEG data packet from the MW75 device.

Each packet carries one sample across all 12 EEG channels plus reference and DRL (Driven Right Leg) values. The MW75 streams at 500 Hz, so one packet arrives approximately every 2 ms.

Wire format

byte[0]       : 0xAA sync byte
byte[1]       : event ID (239 = EEG)
byte[2]       : data length
byte[3]       : counter (0–255, wrapping)
bytes[4..8]   : REF value (f32 LE)
bytes[8..12]  : DRL value (f32 LE)
bytes[12..60] : 12 × f32 LE channel values
byte[60]      : feature status
bytes[61..63] : checksum (u16 LE, sum of bytes 0..61 & 0xFFFF)

Channel scaling

Raw ADC float values are multiplied by the EEG scaling factor (crate::protocol::EEG_SCALING_FACTOR = 0.023842) to convert to microvolts. A raw value of 1000.0 becomes ≈ 23.84 µV.

Example

let packet = EegPacket {
    timestamp: 1710000000.0,
    event_id: 239,
    counter: 42,
    ref_value: 5.0,
    drl: -3.0,
    channels: vec![10.0; 12],
    feature_status: 0,
    checksum_valid: true,
};
assert_eq!(packet.channels.len(), 12);

Fields

timestamp: f64

Wall-clock timestamp in seconds since Unix epoch, captured when the packet was received from the transport.

event_id: u8

Event ID byte from the packet header. Always 239 for EEG data.

counter: u8

Monotonically increasing packet counter (wraps at 255). Used for dropped-packet detection: if counter jumps by more than 1, (counter - last_counter - 1) packets were lost.

ref_value: f32

Reference electrode value (f32, already in correct units).

drl: f32

DRL (Driven Right Leg) electrode value (f32, already in correct units).

channels: Vec<f32>

12 EEG channel values in µV.

Raw ADC float values are multiplied by the scaling factor (0.023842) to convert to microvolts.

feature_status: u8

Feature status byte from the packet.

checksum_valid: bool

Whether the packet checksum validated correctly. Always true for packets returned by crate::parse::parse_eeg_packet (invalid packets are rejected before constructing this struct).

Trait Implementations

impl Clone for EegPacket

fn clone(&self) -> EegPacket

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for EegPacket

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.