Numeric Data Processor (8087)
zSBC 337 PIGGYBACK PROCESSOR
The large number of memory sockets on the ZT 8809A necessitates
the use of Ziatech’s zSBC piggyback processor option if the 8087 is
desired. This 2" x 2" card serves to extend board space by housing the
V20 microprocessor chip and the 8087 coprocessor chip beside one
another.
The base of the zSBC 337 has a 40-pin dual inline socket that
provides elevation from the ZT 8809A. The zSBC 337 module then
plugs into the location normally occupied by the V20 on the
ZT 8809A. This double socket configuration provides the extended
clearance required by the height constraints of the chips residing just
below the piggyback board. The piggyback board hovers partially
above the configurable RAM/EPROM memory socket, which is not
necessarily used for STD DOS and STD ROM. The zSBC 337
therefore should not physically interfere with typical uses of the
ZT 8809A memory sockets. With an 8087 module installed, the
ZT 8809A occupies two 1/2" spacing card slots.
For example, if a 128 Kbyte RAM is to be inserted into the
configurable RAM/EPROM socket at location 3D1 to expand
ZT 8809A memory, a second socket may be needed between the
zSBC 337 module and the ZT 8809A processor socket. This is due to
the height of some hybrid 128 Kbyte RAM modules.
Ziatech
recommends use of an Augat 40-pin collet socket, part number
540-AG19D.
If you have purchased the zSBC 337 as a user, the following
procedure will assist you with its installation on the ZT 8809A.
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