Smiths Medical Medfusion 3000 Series, Техническое и сервисное руководство

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Theory of Operation
33 40-5648-51B
Signal name Processor port Description
write*, e_clock,
xaddr[15:18],
addr[0:14], data[0:7]
R/w*, E, XAD -
DR15 - XAD -
DR18, ADDR0
- ADDR14,
and DATA0
- DATA7
The main processor control bus signals that route to the memory
and I/O expansion devices. The address line addr15 is not used.
spi_clock, spi_mosi,
and spi_miso
SCK, MOSI,
MISO
These signals are used for SPI bus communication to the Serial
EEPROM, Time of Day Clock, Analog to Digital Converter, and the
Digital to Analog Converter.
atod_ref_bfrd AN0 Input for main processor to verify the reference voltage used by the
10-bit analog to digital converter and system reference. The nomi -
nal measured reference voltage is 2.048 volts.
supercap_detect AN1 Analog signal proportional to the Super Capacitor voltage. When
fully charged, supercap_detect measures 2.5 volts nominally. The
main processor read supercap_detect to verify the Super capaci -
tor is present.
pwr_strb_on AN2 Feedback signal is to check the proper operation of the power con -
trol circuit. When power is on, pwr_strb_on measures > 4.0 volts
nominally.
motor_sply_meas AN3 Signal is proportional to the motor supply voltage. The nominal DC
voltage for this signal is 1.09 volts, exactly a sixteenth of the motor
supply voltage.
analog_sply_meas AN4 Signal is proportional to the analog supply voltage. The nominal DC
voltage for this signal would be 2.5 volts nominally, exactly one half
of the analog supply voltage.
force_psv_adj AN5 Feedback signal proportional to the offset voltage used on the force
sensor pre-amplifier. Its voltage range dependent upon the offset
voltage setting (a calibration value).
speaker_detect AN6 Feedback signal proportional to the current through the main
speaker. Its level depends on the volume setting for the speaker.
vpos_sply_meas AN7 Signal is proportional to the positive supply voltage. The nominal
DC voltage for this signal is 2.397 volts, exactly one fourth of the
vpos_sply supply voltage.
mtr_timer PA7/OC1 Time base used by the main processor to control motor step timing
and an input to the highest, maskable interrupt source.
motion_detect PA2/IC1 Signal is the encoded output from the optical motor rotation detec -
tor.
buzzer_detect PA1/IC2 Feedback signal from the audio buzzer detection circuit. This signal
is logic high whenever the audio buzzer is active.
tod_intrpt PA0/IC3 An independent time base provided by the time of day clock. This is
a 1 Hz frequency signal.
MOD_A,
MOD_B
These inputs configure special processor operational modes.