Xerox Document FaxCentre 165c Service Manual page 25

The memory block, divided into the following three sections, is an integral part of
the motherboard:
EPROM
• EPROM (256 Kbytes), this memory contains the system firmware, the default
settings of the software parameters and the messages in the various languages
• STATIC RAM (8 kbytes), this memory contains:
- the current user and service software parameters
- the calibration settings (alignment settings, CCD settings)
- the telephone number list (one-touch dialling numbers, speed code
dialling numbers, broadcasting lists)
- the power failure repor.
• DYNAMIC RAM (512 kbytes), this memory contains:
- the compression and decompression buffer
- the scanning buffer
- the print buffer
- the transaction memory (activity reports)
- the user memory (documents to send, documents received in the memory).
The data is retained in the dynamic memory even during a power failure by a backup
battery capable of powering the system for 72 hours. The facsimile machine must
be left powered for 24 hours to recharge this battery.
The data is retained in the static memory by the 5-year duration system battery.
XEROX DFC165 & DWC 165c Service Manual
Static
RAM
Dynamic
RAM
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