import struct

# Command, index, subindex
SDO_STRUCT = struct.Struct("<BHB")

REQUEST_SEGMENT_DOWNLOAD = 0 << 5
REQUEST_DOWNLOAD = 1 << 5
REQUEST_UPLOAD = 2 << 5
REQUEST_SEGMENT_UPLOAD = 3 << 5
REQUEST_ABORTED = 4 << 5
REQUEST_BLOCK_UPLOAD = 5 << 5
REQUEST_BLOCK_DOWNLOAD = 6 << 5

RESPONSE_SEGMENT_UPLOAD = 0 << 5
RESPONSE_SEGMENT_DOWNLOAD = 1 << 5
RESPONSE_UPLOAD = 2 << 5
RESPONSE_DOWNLOAD = 3 << 5
RESPONSE_ABORTED = 4 << 5
RESPONSE_BLOCK_DOWNLOAD = 5 << 5
RESPONSE_BLOCK_UPLOAD = 6 << 5

INITIATE_BLOCK_TRANSFER = 0
END_BLOCK_TRANSFER = 1
BLOCK_TRANSFER_RESPONSE = 2
START_BLOCK_UPLOAD = 3

EXPEDITED = 0x2
SIZE_SPECIFIED = 0x1
BLOCK_SIZE_SPECIFIED = 0x2
CRC_SUPPORTED = 0x4
NO_MORE_DATA = 0x1
NO_MORE_BLOCKS = 0x80
TOGGLE_BIT = 0x10