GE Corometrics 250cx Series Service Manual page 48

Digital System Processor (DSP) Display PWA
2-20
Equipment Overview: Theory of Operation
The DSP Display PWA consists of two independent functioning modules: the DSP
and the Display interface. The DSP processes analog and digital data from the front-
end modules and interfaces to the main processor. The ECG and ultrasound analog
information is processed and heart rates are output to the main board via a shared
memory. Digital pressure information is received, processed, and also sent to the
shared memory. The Display section, consisting mainly of a shared memory and
timing generator, provides the interface between the LCD and the main processor.
Circuitry for the main processor to adjust the brightness of the LCD is provided
through a DC-to-AC inverter. RS-232 communications between the Main Board and
the UI keypad PWA are routed through the DSP board.
250cx Series Maternal/Fetal Monitor
2036947-001
Revision C