IBM RT PC Options Installation page 178

6-30 Options Installation
• If only the late adapter version is being used, select one J5-J6
combination per adapter from the following table.
• If one early adapter version is used with one or more late adapter
versions, only three of the four J5-J6 combinations are available,
depending on the setting of J3 on the early adapter version:
– When the early adapter version Jumper Module J3 is set
for Primary, select one J5-J6 combination per late adapter
version from the last three rows of the following table.
– When the early adapter version Jumper Module J3 is set
for Alternate, select one J5-J6 combination per late adapter
version from the first, third, or fourth rows of the following
table.
• If two early adapter versions are used with one or more late
adapter versions, only the last two rows in the J5-J6 combination
table are available for use with the late adapter version.