Epson 10020 - Manual (Page 115)

Installing the Optional Controller
First remove the cover of the computer as described earlier in
this chapter. Then see the documentation supplied with the
optional disk drive controller card for detailed instructions on
how to connect the drives to the option card.
The drive cables for drives A and B are normally connected to
connector CN5 on the system board (shown in the following
illustration). If a different cable is supplied to connect the
drives to the optional controller card, make a careful note of
how the original drive cable was connected and remove it from
the computer. Keep it in a safe place in case you need to
remove the optional controller for any reason.
Installing Option Cards
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