Digital Audio Sound Interface Kit file (.DSM) format specification
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Reverse engineering write-up version 0.1 (2024-10-31 🎃)

A little-endian format, uses parapointers (X shl 4 for real offset) so data mostly aligns to 0x10.

Values below are unsigned, numbers hexadecimal.

offset	[length]<shortname>		description
00	[4]	"DSM\x10"
04	[20]	name, 0-padded
25	[1]	"\x1A" (EOF)
26	[1]ord	orderlist positions
27	[1]irec	instrument records, always 1F, real number calculated down below
28	[1]ptn	patterns
30	[80]		orderlist
B0	[irec*2]		parapointers to instruments
B0+irec*2	[ptn*2]		parapointers to patterns

Instrument records follow, each 40 long:
	+00	[4]	"DSI\x10"
	+04	[20]	name, 0-padded
	+24	[2]	parapointer to sample record
	+26	[2]	sample length
	+28	[2]	loop start (can be zero of course)
	+2A	[2]	loop end (can easly be zero, must mean a full sample is played no-loop)
	+2C	[1]	flags? panning? Bit 7 analysed separately, anyway
	+2D	[1]	= 20. panning?
	+2E	[1]	volume within 40
	+2F	[1]	= 0. ???

Patterns follow.
Each pattern begins with an uint16 value that denotes the length of the following chunk. Chunks are 10-aligned.

Samples follow.
The last sample's length isn't aligned to 10.


--Kae
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