CCE MC-1000 data cassette
From Just Solve the File Format Problem
The CCE MC-1000 was a Brazilian home computer system released in 1985. It could store data (such as BASIC programs) on audio cassettes. The cassette format represented the bits of data straightforwardly with different lengths of pulses; a short pulse represented a 1 bit while a long pulse represented a 0 bit. The data was preceded by a synchronization header with 4096 "1" bits and 256 "0" bits.