HP 98568A Installation Instruction page 102

HP 98287 A Graphics Display Station Interface
b. Set these switches to one of the four select codes given in Figure 5-3,
unless you have used them elsewhere. Refer to the installation note that
came with the interface if you need additional switch settings.
~~ ~C!I
Select Code 23 Select Code 24
~~ ~~
Select Code
26 Select Code 30
Figure 5-3.
6. Insert the Interface.
a. Remove the painted cover plates from the back of your computer until
you find an empty even-numbered slot. (Slots are numbered from the top
down, so the top-most slot is number 1, the next slot down is number 2,
etc.) Do not remove the silver cover plates from the bottom of a Series
300 computer.
b. Insert the Graphics Display Station Interface, component side up, into
the empty even-numbered slot. Tighten the thumb screws on the metal
end plate until the end plate is flush with the back of the computer.
c. If you changed the select code of the Graphics Display Station Interface
in step 5, find this number in the set of select code labels supplied with
the interface. Affix this label to the metal end plate.
d. If you have other interface or accessory cards to install, leave the cover
plates off; otherwise, replace them.
7. Record the Select Code.
5-6 Adding Interface Cards