BBC Loopback

Encode a message with BBC and decode it straight back.

Author James Morrison
Category gr-bbc
Blocks 9
Connections 4
File gr-bbc/bbc_loopback.grc

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Blocks used

Block	Module	Used
Variable	`GNU Radio`	4
BBC Decoder	`gr-bbc`	1
BBC Encoder	`gr-bbc`	1
Message Debug	`GNU Radio`	1
Null Sink	`GNU Radio`	1
Vector Source	`GNU Radio`	1

Flowgraph source

gr-bbc/bbc_loopback.grc

options:
  parameters:
    author: James Morrison
    catch_exceptions: 'True'
    category: '[GRC Hier Blocks]'
    cmake_opt: ''
    comment: ''
    copyright: ''
    description: Encode a message with BBC and decode it straight back.
    gen_cmake: 'On'
    gen_linking: dynamic
    generate_options: no_gui
    hier_block_src_path: '.:'
    id: bbc_loopback
    max_nouts: '0'
    output_language: python
    placement: (0,0)
    qt_qss_theme: ''
    realtime_scheduling: ''
    run: 'True'
    run_command: '{python} -u {filename}'
    run_options: run
    sizing_mode: fixed
    thread_safe_setters: ''
    title: BBC Loopback
    window_size: ''
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [10, 10]
    rotation: 0
    state: enabled

blocks:
- name: CHECKSUM_BITS
  id: variable
  parameters:
    comment: Check bits appended to each message; must match at both ends.
    value: '32'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [600, 10]
    rotation: 0
    state: enabled
- name: CODEWORD_LENGTH
  id: variable
  parameters:
    comment: Codeword size in bytes. A larger ratio survives more jamming.
    value: '8192'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [820, 10]
    rotation: 0
    state: enabled
- name: MESSAGE_LENGTH
  id: variable
  parameters:
    comment: Message size in bytes.
    value: '32'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [1070, 10]
    rotation: 0
    state: enabled
- name: message
  id: variable
  parameters:
    comment: Hex bytes, matching Message Debug's display; padded to exactly MESSAGE_LENGTH bytes.
    value: '[0x42, 0x42, 0x43, 0x20, 0x73, 0x61, 0x79, 0x73, 0x20, 0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x20, 0x74, 0x6f, 0x20, 0x47, 0x52, 0x43, 0x6f, 0x6e, 0x32, 0x36, 0x21, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [1300, 10]
    rotation: 0
    state: enabled
- name: bbc_bbc_encoder_0
  id: bbc_bbc_encoder
  parameters:
    affinity: ''
    alias: ''
    checksum_length: CHECKSUM_BITS
    codeword_length: CODEWORD_LENGTH
    comment: ''
    maxoutbuf: '0'
    message_length: MESSAGE_LENGTH
    minoutbuf: '0'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [360, 150]
    rotation: 0
    state: enabled
- name: bbc_bbc_decoder_0
  id: bbc_bbc_decoder
  parameters:
    affinity: ''
    alias: ''
    checksum_length: CHECKSUM_BITS
    codeword_length: CODEWORD_LENGTH
    comment: ''
    max_candidates: '256'
    max_steps: '5000000'
    maxoutbuf: '0'
    message_length: MESSAGE_LENGTH
    minoutbuf: '0'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [800, 150]
    rotation: 0
    state: enabled
- name: blocks_message_debug_0
  id: blocks_message_debug
  parameters:
    affinity: ''
    alias: ''
    comment: Prints each decoded message.
    en_uvec: 'True'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [1330, 260]
    rotation: 0
    state: enabled
- name: blocks_null_sink_0
  id: blocks_null_sink
  parameters:
    affinity: ''
    alias: ''
    comment: The same messages also come out as a byte-vector stream.
    type: byte
    vlen: MESSAGE_LENGTH
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [1330, 160]
    rotation: 0
    state: enabled
- name: blocks_vector_source_x_0
  id: blocks_vector_source_x
  parameters:
    affinity: ''
    alias: ''
    comment: ''
    maxoutbuf: '0'
    minoutbuf: '0'
    repeat: 'False'
    tags: '[]'
    type: byte
    vector: message
    vlen: MESSAGE_LENGTH
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [10, 150]
    rotation: 0
    state: enabled

connections:
- [bbc_bbc_decoder_0, '0', blocks_null_sink_0, '0']
- [bbc_bbc_decoder_0, decoded, blocks_message_debug_0, print]
- [bbc_bbc_encoder_0, '0', bbc_bbc_decoder_0, '0']
- [blocks_vector_source_x_0, '0', bbc_bbc_encoder_0, '0']

metadata:
  file_format: 1
  grc_version: 3.10.9.2