Jersey Jack Pinball The Hobbit, Operation Manual

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Game Service & Troubleshooting E-8
The Hobbit lighting system can be divided into three major subcomponents: communications/control, general
illumination (GI) and feature lighting. One of the primary design criteria for the new system was parallel control of
all lighting in the game; issues with single (or a small group of) LEDs would not affect large areas of the playfield.
Modularity and flexibility were also paramount concerns.
The new communications/control hub is the Bus, Accelerometer and GI (BAG) board; it is mounted, vertically,
under the center of the playfield (circled in red in figure E9). An onboard microcontroller receives data/commands
over a USB connection to the CPU board ( J101 ). Controls are then sent out, over an inter-integrated circuit (I2C)
bus, to the game's light boards - and more. Communicating over an I2C bus, between printed circuit boards (
J102
,
J103 ), adds a great deal of flexibility to the system. Simultaneous control of a wide variety of device types is now
possible. In The Hobbit, this I2C bus is used to control the servo motor that moves Smaug's lower jaw - in addition
to all of the feature lighting in the game.
GI and feature lighting are independent circuits In The Hobbit. GI functions (lighting under playfield plastics, pri-
marily) are accomplished with single color (cool white) LED boards, whereas RGB LED boards are used for feature
lighting (lighting behind playfield inserts, primarily). Since we can control the intensity of the GI board LEDs, they
can also be used for accent lighting (under the playfield, in front of the beast faces in The Hobbit) and as flashers
(under The Hobbit's left & right side playfield plastics).
The control circuitry for GI lighting resides on the BAG board. 7.5VDC is also run through the board to provide
power to all of the GI LED boards around the playfield (above and below). This 7.5VDC is supplied by the 7.5/4VDC
Power Supply, inside the cabinet PCB chassis (item 12, pg C-14 of this manual). The BAG board can control up to
72 GI LEDs, 8 through each of 9 driver connectors ( J105-J113 ).
A pair of wires runs to each GI LED board. One wire (solid GRY) supplies power to the LED, the other (GRY with a
stripe) is the control/return line from the LED; this line is used to vary the LED's intensity. The pairs of wires are
bundled together into cable assemblies (pg C-78). The striped wires are color coded to quickly identify which pins
each LED connects to at the 16-pin BAG board connector. The first LED in each cable has a drive wire with a BLK
stripe, the second has a BRN-striped wire, the third, a RED-striped wire and so on, through the resistor color code
(BLK, BRN, RED, ORN, YEL, GRN, BLU, VIO). Color code references for GI wiring are included in GI wiring PF dia-
grams & tables (pgs C-74 to C-78), BAG board schematics (pg D-59 or D-67) and in BAG board connector pin-out
listings (pg D-60 or D-68).
E.3
The Hobbit Lighting System
Theory of Operation
Figure E9. Hobbit lighting system controller boards.
BAG Bd
RGB LED Controller Bd