GE HEALTHCARE CARESCAPE Monitor B650 Technical Manual page 129

Main processor and memory:
• The main processor manages the data processing of the patient monitor.
• It has non-volatile flash memory for the bootloader software and Linux kernel and volatile
SDRAM memory for run time code execution and temporary data storage.
• A detachable, non-volatile flash memory, USB Disk On Module (uDOM), is used as the
permanent memory for application, platform and service software and to store clinical
and platform settings. The uDOM may hold two versions of the software in different
partitions: inactive and active.
EMBC section:
• The Ethernet module bus controller (EMBC) section in the CPU board has its own micro
controller. It has serial flash memory for the EMBC bootloader software, NAND flash for
EMBC application software and Linux kernel and SDRAM for run time EMBC code
execution and temporary data storage.
• The EMBC section communicates with the main processor using Ethernet
communication.
• The EMBC section takes care of the following CPU services:
• It provides serial communication for the optional built-in recorder.
• It provides RS-485 module bus communication for the E-modules and PSM module.
• It provides analog ECG and invasive pressure outputs and a digital marker-out
signal for a user-supplied equipment, e.g., a defibrillator or an intra-aortic balloon
pump.
Supply voltages:
• The CPU has converters to generate +1.5 V, + 1.8 V and +2.5 V supply voltages for the
processors and +12 V and -12 V voltages for the sync connector signals from the +3.3 V
received from the DC/DC board.
• The CPU board passes the supply voltages created by the DC/DC board for all other
electronics in the system, except for the LED backlight of the display.
System supervision:
• Watchdog timers control the operation of the main processor and EMBC processor
software execution.
• The CPU board has battery backed-up real-time clock to store system date and time.
• An I2C A/D converter and SPI temperature sensor measure the CPU supply voltages and
board temperature.
Video system:
• The CPU board has a video controller that provides LVDS output to the LCD panel via the
display cable and analog and digital video signals for an optional secondary display that
is connected to the DVI-I connector in the interface board.
• The CPU board also provides a brightness control signal and a digital backlight enable
signal for the display.
Audio system:
• The CPU board has a tone generator and audio amplifier that sends the audible alarm
signals to the main speaker. Audio feedback controls the operation of the speaker.
Theory of operation
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