This still has issues, notably:
Despite the first 16kbytes of audio being loaded prior to starting the
AICA ARM7 CPU, the GDROM drive returns "busy" for the following
~48kbytes. This in turn causes the AICA to play audio from
uninitialized memory.
There is also a separate issue where the timing of changing the start
address of the audio channel causes a faint popping sound throughout
the audio playback.
I should do more timing experiments with the GDROM drive, and improve
this example to play the audio with fewer artifacts.
This combines my iso9660 parsing code, with all of the prior gdrom packet
interface / command code.
The example, on real Dreamcast hardware, displays the first 2048 bytes [1] of every
file in the root directory on the serial console.
[1] or the size of the file, whichever is smaller
