IBM 6400 Operation Manual page 19

Configure the MPI by putting the dip
switches in the position that matches the
desired selection.
In the sample printout and the diagnostics,
the following convention is used.
0 = OFF or OPEN
1 = ON or CLOSED
After making MPI switch or cable changes,
the printer must be powered off, wait 15
seconds and then power on the printer in
order for those changes to take effect.
Figure 1 Location of Configuration Switches.
Multi–Platform Interface Feature Operation Guide
note
configuring MPI
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