GSi TYMPSTAR 1, Service Manual

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Hardware Description
Digital board The digital board contains the measurement circuits and general interface to all other
sub assemblies and consists of the following:
· Signal microprocessor
· FPGA– Field Programmable Gate Array
· Microphone signalA/D converter
· Pressure levelA/D converter
· Dual port RAM that provides signal and control processor intercommunication
· Watch dog timer circuit for monitoring hardware and software performance
· Interface to the PC 104 board, analog board, printer board, LCD, internal and
external printers, internal and external keyboards, isolated RS232 port and pump
control circuitry
· Calibration mode entry and option switches
PC104 board The PC104 board serves as the control processor for the TympStar. It is an all-in-
one single-board computer. This 486-based PC interprets and responds to the
keyboard commands and it manipulates the measurement data for display and print-
ing. The PC104 board includes the following:
· Embedded AMD DX5-133 processor (Pentium grade)
· ISA interface to digital board
· Award 128 KB flash BIOS
· System memory 4 MB RAM in SIMM socket
· Supports M-Systems DiskOnChip® 2000 flash disk up to 144 MB
· Enhanced IDE hard disk interface
· RS232 serial port
· Parallel printer port which supports SPP/ECP/EPP modes
· Keyboard/mouse connector
· VGA interface
Analog board The analog board contains all the tone and noise generators and amplifiers as well
as the microphone filters along with all the signal multiplexes including the following:
· Multi-frequency probe tone generation
· Multi-frequency microphone filters
· IPSI tone generation
· Contra tone generation
· Noise generation
· Click generation
· Probe tone, IPSI and contra amplifiers
· Probe interface
· Signal multiplexing for probe tone, microphone, reflex stimuli and pressure signals
GSI TympStar Version 1 and Version 2 Service Manual 7 - 7