

OCEAN-IMAGINE TAPE

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Can be found on... Green Beret, Miami Vice, Mikie, Parallax, Ping-Pong, Rambo, Arkanoid, 
The Great Escape, Head Over Heels, Hypersports, Mutants, Short Circuit, Top Gun, etc.. 

There are 3 different Ocean-Imagine loaders found so far. The differences are very small, 
so almost the same decoding can be used. 

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Threshold : $1E0 (480) clock cycles (TAP byte = $3B).
Bit 0 : $24
Bit 1 : $56
Endianess : LSbF
Pilot : Bit 0 (*3000+)
Sync : Bit 1 
Flag : $AA (only for types 2 and 3) 

Data is structured from sub-blocks, each sub-block is 256 bytes long and has 2 bytes of 
header info. 

1 byte : If it is $01 then loader writes $00 to address $0001.
1 byte : Load address (high byte only).
256 bytes : Data. 



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Notes:- 

The END of loading is signalled by the load address byte being $00 for types 1 & 2, for 
type 3 the end of the loading signalled by this byte being $02. 

Types 1 & 2 usually have some trailing tone present (bit 0's). (which is why reading a $00 
byte at load address can indicate end of loading for these types). 

The format is VERY similar to "Novaload Special".






