Filter
Top Products
7-4 DIGITAL SUBSYSTEM
ASSEMBLIES
The following paragraphs briefly describe the major assemblies that com
-
prise the 373XXA Digital Subsystem. The digital subsystem provides all
system control, I/O interface, digital signal processing, and data pre
-
sentation functions.
The major assemblies that comprise the 373XXA digital PCB subsys
-
tem are listed below. Refer to Figure 7-3, at left.
q
A9, Main Processor PCB
q
A13, I/O Interface #1 PCB
q
A14, I/O Interface #2 PCB
q
A15, Graphics Processor PCB
q
A16, Hard Disk PCB
q
A18, Rear Panel Interface
q
Rear Panel Assembly
q
Front Panel Assembly
q
Floppy Disk Assembly
q
A24, VME Bus Terminator PCB
A9 Main Processor
PCB Assembly
The major components that comprise the A9 Main Processor PCB are:
q
68040 Microprocessor (w/ integrated co-processor) – This is the
CPU for the 372XXB system.
q
4 MB DRAM – This is the main system memory. This memory is
volatile (non-battery backed). During normal operation, it stores
the 372XXB software that is loaded from disk at power-up.
q
8 KB BBRAM – This auxiliary memory chip contains a back-up
battery that is continuously recharged whenever power is ap
-
plied. (The back-up battery has a four year minimum life span.)
This chip also contains real time and date clock functions. It is
used to store low level boot-up parameters, ALC calibration data,
source frequency calibration data, and service log header data.
q
512 KB SRAM – This auxiliary memory is backed-up by a
non-rechargeable Lithium battery that provides 200 days (maxi
-
mum) of power-off protection. It is used to store current and
saved front panel setups, trace/normalization data, current RF
calibration data, current sweep frequency data, flat power cali
-
bration data, and the service log error list.
q
VME Bus interface chip – This chip is used to interface the Main
Processor PCB to the A13, A14, and A15 digital PCBs (via the
VME bus interface).
q
SCSI Bus interface – This chip is used to interface the Main Pro
-
cessor PCB to the A16 Hard Disk PCB.
SYSTEM DESCRIPTION DIGITAL SUBSYSTEM ASSEMBLIES
373XXA MM 7-13