Merlin 3070 Service And Maintenance Manual page 236

CIB 3039
(Z185A1) Feature Module 1
When installed in the appropriate slot (color-coded orange on the control unit
label) in a Model 1030 control unit, Feature Module 1 allows access to all
programs for the system's features. Install this module in the slot labeled 3
on the control unit. The (6800-type) microprocessor in the Processor Module
(installed in the slot labeled 2 and color-coded violet on the control unit label)
runs the programs stored in Feature Module 1. Labels on the Feature Module
indicate the functions of the corresponding switches on the Processor Module
in the slot labeled 2. (See Figure 1.)
Latch
Figure 1.
Feature Module 1