SCSI Tape Emulator

Details: The .tap format is a series of tape records; each record is stored as a 2 byte byte count, the data (sometimes rounded to an even number of bytes), and a repeat of the 2 byte byte count. This format supports the basic tape record operations; you need to keep a pointer to the current record. A 'tape read' retrieves the byte count from the record pointed to by the pointer, retrieves the data, and advances the pointer to the next block. Tape marks are stored as 2 bytes of zeros. Skipping records forward is done by retrieving the byte count and calculating the new pointer value. Skipping backward is done by backing the pointer up 2 bytes, and retrieving the 2nd copy of the byte count of the previous record, and calculating how far back to move the pointer. Rewind sets the pointer to 0.