Byte-Level Packing - Byte-Level Packing - 2026.1 English - UG1864

Vitis Functional Simulation User Guide (UG1864)
Document_ID
UG1864
Release_Date
2026-06-23
Version
2026.1 English

When an array carries an axis configuration, arr.bytes returns the packed uint8 stream used for HLS AXI4-Stream simulation. The stream includes the payload data and enabled sideband fields.

Language How to Get Packed Bytes
Python arr.bytes: Read-only property. When axis is configured, returns the axis-packed beat stream. When no axis is configured, returns the plain data bytes.
MATLAB arr.bytes: Read-only property. When axis is configured, returns the axis-packed beat stream. When no axis is configured, returns the plain data bytes.

Python:

arr = va.array(np.array([10, 20, 30], dtype=np.int32),
               dtype=va.int32, axis=va.axis())
arr.tlast[-1] = 1

packed = arr.bytes   # uint8 numpy array of packed beats (data + sidebands)

MATLAB:

arr = varray.int32([10, 20, 30], axis=varray.axis());
arr.tlast(3) = 1;

packed = arr.bytes;   % uint8 vector of packed beats