schematic_312503_diptrace.dch: Schema was designed in DIPTRACE (https://diptrace.com/). They provide a free Version (300 pins and 2 signal layers, non-profit use only). High recommendation!
schematic_312503_eagle.sch: Exported from DIPTRACE for EAGLE CAD (untested!)
schematic_312503_pcad_ascii.sch: Exported from DIPTRACE (untested!)
schematic_312503_diptrace_ascii: Exported from DIPTRACE (untested)
Use at your own risk