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SID_file_format.txt  view on Meta::CPAN

This is a four byte long ASCII character string containing the value
0x50534944 or 0x52534944. 'RSID' (Real SID) denotes that the file strictly
requires a true Commodore-64 environment to run properly. 'PSID' files will
generally run trouble-free on older PlaySID and libsidplay1 based emulators,
too.

Some words about the Real C64 SID file format (RSID):

The RSID format was designed to contain tunes that are not PlaySID compatible,
but strictly require a real C64 environment to run. Tunes that are multi-speed
and/or contain samples and/or use additional interrupt sources or do busy
looping will cause older SID emulators to lock up or play very wrongly (if at
all).

By using the name RSID for such rips all existing SID emulators will reject
these tunes safely until they can be upgraded to cope with the additional
requirements.

Due to the nature of these tunes, every effort must be made to make sure they
are directly runnable on an actual C64 computer. As such the tunes will only
be presented with the default C64 power-on environment and expected to