LUMENIS VersaPulse PowerSuite - 4.4.2 Microprocessor

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Fiber and Blast Shield Position Sense Circuits - Monitors the position of the fiber and blast shield.
Described in subtopic 4.4.9.
Service Attenuator Circuits - Operates and monitors the position of the service attenuator. Monitors
the condition of the service and diagnostic push-buttons located on the CPU PCB. Described in sub-
topic 4.4.10.
Low Energy Attenuator Circuit - Operates and monitors the position of the low energy attenuator.
Described in subtopic 4.4.11.
4.4.2 Microprocessor
Refer to 8-8 in Section 8. The Motorola MC68000 microprocessor U64 reads/writes to its memory and I/O
devices over a 23 bit address bus and 16 bit data bus. The following ICs generate clock signals to operate the
various discreet devices throughout the Controller PCB:
• U59 generates a 16 MHz clock signal to the microprocessor and the ChipSelect/ Interupt
EPLD U62. The 16 MHz signal can be seen at TP83.
• U48 generates a 2.457 MHz signal to the Multifunction Programmable Timer U47.
• U34 generates 1 MHz signal to the Safety Control Logic EPLD U40.
• U65 generates a 24 MHz clock signal to the Lamp Volts Frequency and the Lamp Energy
Frequency Generators U45 and U46.
U62 serves as:
• A chip select function to decode the upper four bits of the address bus to enable the appro-
priate memory or memory mapped devices.
• A /DTACK/ generator which communicates to the microprocessor that data has either been
sent or received by the EPROMs, RAM, NVRAM, EPLDs, A/D converter or D/A converter
and all other peripherals.
• A clock decoder which generate 1, 2, 4 and 8 MHz clock signals to operate the Digital Input/
Output EPLD U49, Multifunction Programmable Timer U47, Safety Control EPLD U40, A/
D converters U30 and U31.