I need to find a source of information (.PDFs, if possible) about
"80-pin SIMM" "flash memory modules", above 16MB in capacity. These
modules are similar to the 72-pin RAM modules, formerly used in the
PCs, with the only difference that they are (usually) electrically
erasable, programmable ROMs. They are still used in the field of
embedded systems, when they require big amounts of preprogrammed data
or need to log real-time events.

I need not only the pinout but also their schematic and, possibly, the
programming algorithms. Even one .PDF, providing this info for a 64MB
module is enough.

The manifacturer is irrelevant.

The reason I cannot find such info so far is that they are rarely
used, there isn't a specific name for these modules and the search
results tipically are "shadowed" by all kinds of flash cards like SD,
MemoryStick, CompactFlash etc.

intel based 80 pin 64mb simm pinout/functional block

http://www.gaw.ru/pdf/White/1f0a8152.pdf

Thank you f111x-ga. 
I guess I'll have to become more keen in searching documents online... :)