78 SCSI Interface circuit pack
297-1001-536 Standard 01.03 August 1996
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32 KBytes of data RAM with plug–in slots for up to an additional 256
Kbytes.
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Up to 64 KBytes of program PROM.
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Support for disconnect/reconnect operation on the SCSI bus.
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Single error detection parity guard on DPR memory.
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50 pin access port for logic analyzer, emulator and test support (factory
use only).
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RS–232 compatible port for local diagnostics.
System interface is via the 100–pin edge connector.
The EPROM at U3 is a 27C512 type. Removing jumper P1 and making the
appropriate changes to the decode PAL at U23 allows a 27C256 type to be
used.
See Table 9–1 for option settings on this circuit pack. Figure 9–1 shows the
jumper locations and circuit packs’ layout.
Replacing the SCSI circuit pack
Use the following procedure to replace this circuit pack.