ICS Advent PB751-AT Product Manual page 19

PB751-AT MANUAL
As described in the previous section of this manual, DIP switches A2 through A9 are used to
set the base address. The A2 position corresponds to the least significant bit of the address in
hexadecimal code and the A9 position corresponds to the most significant bit. If a block size of
four bytes is selected for an I/O card application (or 2K bytes for memory operation), then all
eight switches are available to set the base address. If one or more block reserving jumpers are
installed, then certain DIP switches MUST be placed in the off position as follows:
8 Bytes I/O or 4KB Memory:
16 Bytes I/O or 8KB Memory:
32 Bytes I/O or 16KB Memory:
64 Bytes I/O or 32KB Memory:
128 Bytes I/O or 64KB Memory:
256 Bytes I/O or 128KB Memory: A2, A3, A4, A5, A6 AND A7 must be OFF
512 Bytes I/O or 256KB Memory: A2, A3, A4, A5, A6, A7 AND A8 must be OFF
Eight or 16-bit Operation
For 16-bit operation, it is necessary to complete wiring on IC U7 and to add a 74LS125 as
shown within dotted lines on the schematic. Further, you may require different or additional
circuitry depending on how you wish this card to interface to the computer I/O bus.
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A2 must be OFF
A2 AND A3 must be OFF
A2, A3 AND A4 must be OFF
A2, A3, A4 AND A5 must be OFF
A2, A3, A4, A5, AND A6 must be OFF
OPTION SELECTION
MANUAL 00650-100-10