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4.15 MUX5 and MUX5E boards
Most gaming machines use more lamps, LEDs and illuminated push buttons than can be
controlled directly by the MPU6 board. The MUX5 board block diagram is shown in Fig. 28
and provides the MPU6 system with the ability to control additional devices. The MUX5E is
similar to the MUX5 in design, but provides an additional 64 lamps.
The functions are detailed below:
•
128 lamps (+ 64 for MUX5E).
•
64 LED segments (i.e. eight 7-segment displays with decimal point)
•
16 illuminated push buttons
•
Alphanumeric display
•
The MUX5 board is controlled by the MPU5 system via the Barbus bi-directional
serial link at data rates up to 100 Kbits/second.
4.16 Processor
The various drivers on the MUX5(E) board are directly controlled by an 8-bit single chip
processor (cpu) in response to MPU6 system commands. The CPU runs at a clock
frequency of either 16 MHz or 12 MHz, the device and associated crystal being selected
during manufacture.
The CPU receives serial data via the Barbus interface concerning changes required to the
pattern of illuminated lamps, push buttons, alphanumeric displays and LEDs. Required data
is strobed from two parallel ports through open drain latches to the appropriate interface
drivers. A third parallel port provides control signals and strobes for the various interfaces,
and accepts a Lamp Sense input from the lamp driver circuits.
4.17 Lamp drives
The lamp drive interfaces are the same as the MPU5 interface described in Sect. 4.1.7, but
on the MUX5 board there are two such interfaces enabled by different strobe signals. One
interface has outputs to two green 17-way connectors LAMPS1 and LAMPS2, wired in
parallel, the other has outputs to a blue 17-way LAMPS3 connector. As on the MPU5 board,
each connector has blue select wiring and green drive wiring.
A total of up to 128 lamps can be wired to the LAMPS connectors. The LAMPS1 and
LAMPS2 connectors can be wired with any combination of lamps provided the total number
of lamps does not exceed 64. The LAMPS3 connector can be wired with up to 64 lamps. On
MUX5E there are a further 64 lamps provided by the Lamps4 connector.
4.18 Lamp current sensing
The lamp current sensing circuit monitors the cold switch-on current of each selected lamp,
providing a short 5.1V pulse to the cpu for a serviceable lamp. If no pulse is received,
probably due to an open circuit lamp, no action is taken until a Self Test routine is carried
out. If the received pulse is at 5.1V for the entire 1.6ms selection period, probably due to a
short circuit lamp, the cpu tries several times to select the lamp, then removes power from
the group of lamps containing the unserviceable device for approximately four seconds
before repeating the selection attempt.
Содержание MPU6
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