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(16) With the exception of the six headers at P201–P204 and at P205–P206, which have
not yet been installed, this completes assembly of the microcontroller circuit board.
VII. Final Assembly of the Controller
(1) Retrieve the previously assembled main circuit board, and recall that during assembly
you inserted 12 pin headers at P201–P204, and 4 pin headers at P205–P206 into their
mating connectors. Verify again that these headers are fully seated into their connectors.
Now set the microcontroller circuit board on top of the main circuit board, so that the
pins on the six headers extend into their holes on the microcontroller circuit board. Do
not solder the pins, yet.
(2) Carefully attach the main circuit board and microcontroller circuit board assembly to
the rear panel, taking care not to let the pins on the six headers slip out of their pads.
These boards attach to the rear panel with the eight jack screws that secure the three 25-
pin DB25 connectors and the 9-pin DB9 connector. Before you tighten the jack screws,
make sure the bodies of the 8-pin RJ-45 (RELAY/CTRL) and 6-pin RJ-25 (REM IN,
REM OUT) connectors fit into their rectangular cutouts on the panel. The jack screws are
rather fragile, so do not overtighten them.
Note: do not attach the rear panel circuit
board to the rear panel yet.
The main circuit board and microcontroller circuit board attach to the
rear panel with the eight jack screws that secure the DB25 and DB-9
connectors.
(3) Check again to make sure that the pins on the six headers at P201–P204 and P205–
P206 are still in their circuit board pads. Then solder the end pins on each header so you
can make certain the header bodies are seated flat against the underside of the
microcontroller circuit board. Now solder the remaining pins.
(4) As shown below, attach the left and right side enclosure brackets to the rear panel,
using the 6-32 x 3/8” screws supplied with the enclosure (not with the hardware packs).
Do not use any washers. Note that the lip on the side brackets will fit into the notches
previously cut into the two circuit boards.
