OpenAllegroParser

Purpose of this project is to provide a C++17 library for parsing Cadence's Allegro binary file formats. This library can be linked to other software for reading Allegro's binary files and/or exporting them to XML files.

See also the complementary project OpenOrCadParser.

The focus lies on

• *.brd board database,
• *.mdd module definition,
• *.dra drawing,
• *.psm package symbol,
• *.ssm shape symbol,
• *.fsm flash symbol,
• *.osm format symbol,
• *.bsm mechanical symbol, and
• *.pad padstack.

See OrCAD Allegro Files Extension and their Contents or Cadence Allegro file Extensions and what they contain for more information on the file purpose.

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Documentation

• File Formats
  1. *.brd Board Database
  2. *.mdd Module Definition
  3. *.dra Drawing
  4. *.psm Package Symbol
  5. *.ssm Shape Symbol
  6. *.fsm Flash Symbol
  7. *.osm Format Symbol
  8. *.bsm Mechanical Symbol
  9. *.pad Padstack

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Current State — April 2022

• Working on padstack to XML exporter

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Build

cmake -B build -S . -DCMAKE_TOOLCHAIN_FILE=../vcpkg/scripts/buildsystems/vcpkg.cmake
cmake --build build

Dependencies

• Compiler with C++17 Support
• CMake >= 3.5
• Boost - Program Options
• fmt
• libzippp
• Magic Enum
• Nameof
• spdlog
• TinyXML2
• vcpkg

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Usage

I tested with some pads created with version 17.4-2019 S019 (3959056) [7/8/2021] which works mostly fine. In case you find pads that do not work - with the specified version - please create an issue and append your *.pad as well as *.pxml files.

Note:

Pad files have some structures with dynamic size where I haven't found a way to calculate those sizes. A workaround to this issue is to brute force all combinations and see when the parser runs without errors. Brute force sounds like a tedious job to do. However, it's quite fast because the amount of possible combinations is relatively low.

Therefore, modify the path to your pad in find_parameter_set.py and run it with python3 find_parameter_set.py. Hopefully there is a parameter set found that works for your file, and you will see an output similar to the following.

---------------------------------------------
------- Found valid Parameter Set -----------
---------------------------------------------

./build/OpenAllegroParser -i simple_example.pad --numUserLayers 5 --bool1

Add the flag -p to the command from above and run it as ./build/OpenAllegroParser -i simple_example.pad --numUserLayers 5 --bool1 -p and you will see a similar output with all the pad's information like the one below. At the beginning a lot of debug output is shown that might be not as interesting for you, as for me. Just scroll down to the more important pad information.

Click to expand

./build/OpenAllegroParser -i simple_example.pad --numUserLayers 5 --bool1 -p

Opening file: "simple_example.pad"
File contains 5020 byte.
File found at 0x00000ed8: simple_example.zip

...

-----------------------------------------------
--------------- File Content ------------------
-----------------------------------------------
PadFile:
  swVersion = pad395907/8/2
  accuracy  = 1
  unit      = mils
  strIdxPadName       = 30 (SIMPLE_EXAMPLE)
  idxUnknown          = 31
  strIdxDrillToolSize = 32 (SIZE_XYZ)
  drillmethod     = ETCH
  holeType        = CIRCLE
  staggeredDrills = 0
  plated          = 1
  not_suppress_nc_internal_pads = 1
  isPolyVia       = 0
  padstackusage   = THRU_PIN
  drill_rows      = 1
  drill_columns   = 1
  lock_layer_span = 1
  offsetX         = 0
  offsetY         = 0
  clearance_columns = 1
  clearance_rows    = 2
  finished_size     = 4
  positivetolerance = 2
  negativetolerance = 1
  width             = 10
  height            = 20
  figure            = CROSS
  characters        = X
  back_drill_figure_width  = 0
  back_drill_figure_height = 0
  back_drill_figure        = NONE
  back_drill_characters    =
  counter_drill_diameter          = 0
  counter_drill_positivetolerance = 0
  counter_drill_negativetolerance = 0
  counterangle         = 0
  genericLayers:
    0: Pad:
      type   = 0
      layer  = 0
      figure = RECTANGLE
      offset = (0.020000;0.030000)
      width  = 0.100000
      height = 0.100000
    1: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    2: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    3: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    4: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    5: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    6: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    7: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    8: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    9: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    10: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    11: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    12: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    13: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    14: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    15: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    16: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    17: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    18: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    19: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    20: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    21: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    22: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
    23: Pad:
      type   = 0
      layer  = 0
      figure = CIRCLE
      offset = (0.020000;0.030000)
      width  = 0.100000
      height = 0.100000
    24: Pad:
      type   = 0
      layer  = 0
      figure = NONE
      offset = (0.000000;0.000000)
      width  = 0.000000
      height = 0.000000
  dateTime1         = Thu Dec 30 20:57:49 2021

  username          = domin
  dateTime2         = Thu Dec 30 20:57:49 2021

  dateTime3         = Thu Dec 30 20:57:49 2021

  dateTime4         = Thu Dec 30 20:57:49 2021

  dateTime5         = Thu Dec 30 20:57:49 2021

  dateTime6         = Thu Dec 30 20:57:49 2021


Closing file: "simple_example.pad"

./build/cli/OpenAllegroParser-cli --help
Allowed options:
  -h [ --help ]         produce help message
  -p [ --print ]        print file content to terminal
  -e [ --extract ]      extract files from within the binary
  -i [ --input ] arg    input file to parse
  -o [ --output ] arg   output path (required iff extract is set)
  -x [ --export ]       export XML file
  -v [ --verbose ]      verbose output
  --export-version arg  Version of padstack_editor.exe used for pxml export
  --bool0               bool0
  --bool1               bool1
  --bool2               bool2
  --int0 arg            int0
  --numUserLayers arg   number of user layers
  --additionalStr2 arg  number of additional strings e.g. symbol names

./build/cli/OpenAllegroParser-cli --input file.pad --extract --output out/
Opening file: file.pad
File contains 4960 byte.
File found at 0x00000abc: file.zip
Extract ZIP file: file.pad/file.zip
Extract from ZIP, 4200 Byte file: out/file.pad/Users/%USERNAME%/AppData/Local/Temp/#Taaaaaa00765.tmp
Closing file: file.pad

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Related Projects

kicad-allegro (Rust based Allegro Extract (ASCII) to KiCad Converter and Viewer)

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How to Contribute?

There are different ways to help this project forward. Some are

• provide test files (manually created or automated via SKILL),
• help reverse engineering/documenting the file format, or
• implement some unit tests.

In case you don't have access to OrCAD PcbDesigner or Allegro you can get Cadence Allegro Viewer free of charge.

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