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It uses the mi4 firmware format. Use mi4code to decrypt and start working on a port. Chances are existing PP/mi4 work are similar.
you mean there are people working on mi4 firmwares for other players?
#mi4code decrypt -s pp5020-org.mi4 pp5020-decrypt.mi4mi4code v1.1.2-DSA (c) by MrH 2008Secondary label end offset 'default' (0xec)Decrypted ok with key 'default' (20d36cc0 10e8c07d c0e7dcaa 107eb080)#mi4code encrypt pp5020-decrypt.mi4 pp5020-encrypt.mi4 20d36cc0 10e8c07d c0e7dcaa 107eb080mi4code v1.1.2-DSA (c) by MrH 2008Invalid magic in mi4 header (maybe not mi4 file)!
#mi4code decrypt -s pp5020-org.mi4 pp5020-decrypt.mi4mi4code v1.1.2-DSA (c) by MrH 2008Secondary label end offset 'default' (0xec)Decrypted ok with key 'default' (20d36cc0 10e8c07d c0e7dcaa 107eb080)
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