KORG M1 w/ Plus+1 Upgrade complete *ROM set
dumped by dbtx

Contents / notes:

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IC20.bin
IC26.bin
IC30.bin

These are three 512Kbit mask ROMs with identical contents-- but they are
used in different ways. Their A14 and A15 address inputs are tied high or
low to select a different region for the different DSP IC each is supplying.
Presumably it was cheaper for KORG to have the same data on fewer and slightly
larger unique ICs, except IC30-- its access latency is slightly lower and it
bears a KORG logo.
IC20 uses the last 16KB (A14 and A15 tied high)
IC26 uses the 16KB just below that (A15 high, A14 low)
IC30 uses the first 32KB (A15 tied low, A14 in use)

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U201.bin
U202.bin
U203.bin
U204.bin

These are 8Mbit each for the Plus+1 multisounds (PCM) on the substitute rear PCM
card slot PCB (replacing KLM-1264). They're mask ROMs in word mode
(#BYTE is tied high).

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IC36.bin
IC37.bin
IC38.bin
IC39.bin
IC40.bin
IC41.bin
IC42.bin
IC43.bin

These are 4Mbit each mask ROMs for the original M1 16-bit PCM multisounds. #BYTE
is tied low and they are paired up-- their layout is such that 36,37,38,39 are
LSB data and 40,41,42,43 are MSB. So--
36 & 40 hold the first 512K samples;
37 & 41 ""
38 & 42 ""
39 & 43 hold the last.  

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plus+1_prog_card.bin

This is the 256Kbit read-only program card that contained all the factory
patches which would utilize the Plus+1 multisounds.

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plus+1_lsb.bin
plus+1_msb.bin

These are 512Kbit each modified OS ROM, for the sockets IC32 and IC23 holding
the low and high bytes respectively. The new names and addresses of the extra
multisounds in U20x.bin are also kept here.

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Thanks to:
Jonas Tyler Doran- for access to the M1 with the upgrade, and for permission
Trammell Hudson- for the Teensy-based dumper (https://bitbucket.org/hudson/prom)
