Activision tape
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By Luigi Di Fraia <armaeth@libero.it>

Used in Activision releases ("Ghostbusters", "Hacker", "On Court Tennis" and probably many others).

After CBM files (DATA size: bytes, CRC32: $8E027BD2) there's another CBM Data block containing the loader. It checks for autostarting cartridges (eg. SIMON's BASIC) and disk drives. If any is found, usually load doesn't end successfully.

Turbo blocks:

      Threshold: $0118 (280) microseconds (TAP value: $22)
      Bit 0 pulse: $1F (very close to threshold)
      Bit 1 pulse: $31
      Endianess: MSbF

      Leader: Bit 1 pulses (no less than x256, typically x2048 about) with last one being bit 0
      Sync byte: $33
      Header: Load address (low/high bytes)
              End Address-1 (low/high bytes) (add 1 to this to get end address)


      Data

      1 byte: XOR checksum of all data bytes