Unknown Pinnacle Micro NuBus cards - 1990

[JRL]

Hi all,

I got these a bit back and was wondering if anybody knew what these cards do. They do not have any external ports, and I can't find much online either.

Thank you for any advice as usual! 

https://imgur.com/a/vso2PoV

-J

 

[IlikeTech]

What do the big PLCC chips in sockets say on them?

 

[cruff]

WIth all that fast SRAM on the board and no I/O connectors, I'm guessing the square unmarked chip in the corner is meant to offload some kind of processing function.

 

[IlikeTech]

Yea I was kinda figuring that, that's why I'm wondering what that chip is.  That board has a TON of SRAM on it

 

[cruff]

Wonder if they are the Pinnacle Micro "Gold Card", which was a disk compression processor.  I found this bit of text in a search for "pinnacle micro nubus":

Compression boards put the speed on squeeze: Sigma's DoubleUp and Pinnacle Micro's Gold Card being near-instantaneous compression to
  Sigma Designs Inc's DoubleUpand Pinnacle Micro Inc's Gold Card
           file compression boards provide compression without data loss,
           avoiding speed problems found in boards that employ loss-prone
           compression.  These boards have fast enough compression and
           decompression speeds that users can keep most of their files in a
           compressed format.  Sigma claims that its DoubleUp works eight
           times faster than software-only compression and offers an average
           ratio of 2-to-1.  The board comes with DiskDoubler software that
           lets users select and compress a hard disk from the desktop.
           Pinnacle Micro Inc contends that its Gold Card can expand disk
           capacity by two to seven times.  The product compresses and
           decompresses 20 times faster than software-only compression.  Both
           cards run on Mac II-family microcomputers.  DoubleUp is currently
           available and Gold Card is expected to ship in late April 1991.