BRO

Status

Field	Value
Extension(s)	.bro
Common ecosystem	Bits & Volts lead
Format family	Machine-specific lead
Satin Studio status	Researching
Open / import	No
Export	No
Confidence	Low-medium.

What it is

BRO is tracked as an embroidery format lead associated with Bits & Volts references.

Satin Studio direction

Research lead only.

Versions and variants

Unknown.

File identification notes

Reported structure includes a 256-byte header and x == 0x80 control-event encoding. Reported command values include stop and jump controls, but the full command map is not verified.

Observed structure notes

• Observed BRO readers skip to offset 0x100 before reading stitches.
• Normal stitch movement is a two-byte signed dx, dy pair. A first byte of 0x80 switches to a control form where an additional control byte follows.
• Observed controls include 0x02 and 0xE0 as end-like commands, 0x7E and 0x03 as long signed 16-bit little-endian movement commands, and 0xE1 through 0xEF as needle-change controls followed by long movement.

Structure sketch

The observed BRO stitch stream starts at offset 0x100:

struct BroFile<'a> {
    header: [u8; 0x100],
    records: &'a [BroRecord],
}

enum BroRecord {
    Stitch { dx: i8, dy: i8 },          // two signed bytes when first byte != 0x80
    End { control: u8 },                // observed 0x02 or 0xE0 after marker
    LongMove { control: u8, dx: i16, dy: i16 }, // 0x7E or 0x03; signed 16-bit LE
    NeedleMove { needle: u8, dx: i16, dy: i16 }, // controls 0xE1..0xEF
    UnknownControl { control: u8 },
}

What we still need

Known-source files, command mapping, and reader validation.