GE Dash 3000, Service Manual

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Revision A Dash 3000/4000 Patient Monitor 9-13
2000966-339
Assembly Drawings: Theory Of Operation
Main Microcontroller
The microcontroller contains two processors:
„
a true internal and external 32-bit CPU core, and
„
a communications processor module (CPM).
The CPM contains an 8 Kb dual port RAM to communicate with the CPU
core, and once configured communicates with external devices with
minimum CPU intervention. External logic is reduced by the internal
memory controllers and a system interface unit which provides a clock
synthesizer and timers used in this design. Writer communications is
supported by direct memory access and processing performance is
enhanced by 4-kilobyte instruction and data caches.
Microcontroller Feature Monitor Function
Serial Communications Controller 1 Unity Network
Serial Communications Controller 2 DAS communication
Serial Management Controller 1 Peripheral expansion communication
Serial Management Controller 2 Reserved
Interprocessor-Integrated Controller Batteries, battery charger,
Real-time clock,
EEPROM,
digital potentiometer for display
brightness control
Serial Peripheral Interface DAC for ECG and BP analog outputs;
ASIC configuration
User Programmable Machine A Memory controller for synchronous
graphics RAM
User Programmable Machine B Memory controller for synchronous flash
General-Purpose Chip-Select Machine Memory and peripheral device control
LCD Controller Color display
PC Card Controller Future use
DMA Writer communication
System Phase-Locked Loop (SPLL) Generation of system clock from crystal
oscillator