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#!/usr/bin/env python3
# -*- coding: utf-8 -*-
# Copyright 2019 Athanasios Theocharis <athatheoc@gmail.com>
# This was made under ESA Summer of Code in Space 2019
# by Athanasios Theocharis, mentored by Daniel Estevez
#
# This file is part of gr-satellites
#
# SPDX-License-Identifier: GPL-3.0-or-later
#
'''
Construct for the Primary Header of the CCSDS Telemetry Space Data Link Protocol
( CCSDS 132.0-B-2 )
'''
from construct import *
PrimaryHeader = BitStruct('transfer_frame_version_number' / BitsInteger(2),
'spacecraft_id' / BitsInteger(10),
'virtual_channel_id' / BitsInteger(3),
'ocf_flag' / Flag,
'master_channel_frame_count' / BitsInteger(8),
'virtual_channel_frame_count' / BitsInteger(8),
'transfer_frame_secondary_header_flag' / Flag,
'synch_flag' / Flag,
'packet_order_flag' / Flag,
'segment_length_id' / BitsInteger(2),
'first_header_pointer' / BitsInteger(11))
OCFTrailer = BitStruct('control_word_type' / Flag,
'clcw_version_number' / BitsInteger(2),
'status_field' / BitsInteger(3),
'cop_in_effect' / BitsInteger(2),
'virtual_channel_identification' / BitsInteger(6),
'rsvd_spare1' / BitsInteger(2),
'no_rf_avail' / Flag,
'no_bit_lock' / Flag,
'lockout' / Flag,
'wait' / Flag,
'retransmit' / Flag,
'farmb_counter' / BitsInteger(2),
'rsvd_spare2' / Flag,
'report_value' / BitsInteger(8))
FullPacket = Struct('primary' / PrimaryHeader,
'payload' / Byte[this._.size],
'ocftrailer' / If(this.primary.ocf_flag == 1, OCFTrailer))
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