7.1
BD4002 Micro Section
Real Time Clock
, this enables the micro to display the date/time on the trace and
front panel. User setup information is held within internal memory of the clock.
Watchdog Timer
, this monitors the micro and checks for any system errors. Upon
detecting a system error the micro is reset. All controls revert to switch-on settings.
Event Marker
, this patient event marker records a mark on the printout in a different
place from the clinical event marker accessed via the front panel (see user manual).
Serial Ports
, the rear connector PCB supports two D-type RS232 connectors for
external interfacing.
Display PCB
, is mounted on the top half of the case moulding and consists of two
separate PCBs joined by a short ribbon cable. This also carries the system controls.
ROM
, the ROM memory contains the program.
RAM
, the main PCB has three RAM IC's, two are used on the Digital Signal
Processing section and the third for data processing by the micro.
Digital Signal Processor
, processes the information from the ultrasound and ECG
transducers implementing autocorrelation and ECG detection for deriving the FHR.
DSP Bootup
, this circuitry loads the DSP program from EPROM to the DSP's
internal RAM when the unit is reset.
EEPROM
, used for storage of user setup information when the unit is switched off.
26
Issue: 2 Draft
Rev: a
614365