

FIREBIRD LOADER 

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Two types are found so far, the only difference is thresholds. 

T1 used on... Denarius, Pitfall, River Raid, Zenji. 

T2 used on... Black Lamp, Druid 2, Sidewize, Micro Rhythm, Scary Monsters. 

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T1 Threshold = tap byte $62 ($320 clock cycles)
Bit 0 : $44
Bit 1 : $7E


T2 Threshold = tap byte $52 ($29A ms)
Bit 0 : $45
Bit 1 : $65


Endianess : LSbF
Pilot byte : $02 (*254)
Sync : $52,$42.

Then... 

2 bytes : Load Address (LSBF).
2 bytes : End Address (LSBF).
n bytes : Data
1 byte : XOR checksum of all n Data bytes.






