Godbout Econoram X control settings

Frank McConnell fmc at reanimators.org
Sat May 25 13:05:07 CDT 2002


Jim Battle asked for info on how his Econoram X is configured.  I
finally got the manual out to look at it.  Guess I should scan it
(12pp) before I put it away again.  

Econoram X is a 32Kx8 RAM board, designed for compatibility with
the proposed IEEE standard for the S-100 bus.  Date on the manual
is 1/79.

The board is addressable as three blocks of RAM: two blocks of 8KB
called blocks A and B, and one block of 16KB called block C.  The 8KB
blocks reside at 8KB boundaries and the 16KB block resides at a 16KB
boundary.  Each block may also be disabled.  Blocks A and B can be write
protected, and each half of block C can be write protected.

S1:
  1: block A write enable (write enabled if on, protected if off)
  2: block B write enable
  3: block C lower 8KB write enable
  4: block C upper 8KB write enable
  5: block A disable (disabled if on)
  6: block B disable
  7: block C disable
  8: write strobe select
     grounds S-100 bus pin 68/MWRITE, should be off if your front
     panel or CPU board drives this

S2:   
  1-3: block A base address (1,2,3 are address bits 15,14,13)
  4-6: block B base address (4,5,6 are address bits 15,14,13)
  7-8: block C base address (7,8 are address bits 15,14)

J1: (down by bus connector, near U7)
  if installed, board supports PHANTOM feature

(Note there is also an Econoram Xa which is different: it is two
16KB blocks which can be located within a 64KB extended-address
block, i.e. it knows about the IEEE 696 extended addressing, unlike
the Econoram X.)

-Frank McConnell



More information about the cctalk mailing list