Lexicon MPX-1 - Using 2167 16 K X 1 Type RAM Chips; Configuring the MPX-L for Different Size EPROMS; Using a 2716 or 2732 EPROM; Using a 2764 EPROM

17), and J18 is located at the right-hand side of the RAM array.. The RAM chips
come in 18 pin packs, but the sockets are 20 pin to accomodate 2167 type RAMs.
When using 2147 type RAMs, plug them in so that the chips are in the bottom-most
part of the socket, that is pins 1 and 20 are blank.
USING 2167 16lCx1 TYPE RAM CHIPS
To use 2167 type RAM chips, jumper J18 should be installed and jumpers Jll-
17 should be open. Jumper J18 is located at the far right-hand side of the Rfu~
array and jumpers Jll-17 are located in-between the RAM chips.
CONFIGURING THE MPX-l FOR DIFFERENT SIZE EPROMS
The MPX-1 has a JEDEC 28 pin socket for the EPROM (U27). With the use of
one jumper, this socket can accomodate a 2716, 2732 or a 2764 type EPROM. This
gives 2K, 4K or 8K of storage, respectively.
USING A 2716 or 2732 EPROM
To use a 2716 or 2732 type EPROM, jumper J19 should have a shorting plug
installed connecting pins "A" and "c" (left of center). J19 is located just
above U26. The 2716 or 2732 should be installed at location U27 such that it
uses the bottom-most pins of the socket, that is pins 1,2,27 and 28 are left
blank.
USING A 2764 EPROM
To use a 2764 type EPROM, jumper J19 should have a shorting plug installed
connecting pins "c" and "B" (right of center). J19 is located just above U26.
The 2764
should be installed at location U27, and all the pins of the socket are
used.
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