Ricoh B079, Service Manual

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BOARDS
B547 120 SM
ROM
• 3MB flash ROMs for system software storage
2MB (16bit x 1M) + 1MB (16bit x 512K)
DRAM
•
The DRAM is shared as follows.
•
SAF
Standard: 4MB
With optional expansion memory: 32MB (4MB + 28MB)
•
Page Memory
Standard: 4MB (Print: 2MB + Scanner: 2MB)
With optional expansion memory: 12MB (4MB + 8MB)
(Print: 8MB + Scanner: 4MB)
•
The SAF memory is backed up by a rechargeable battery.
SRAM
•
The 512 KB SRAM for system and user parameter storage is backed up by a
lithium battery.
Memory back-up
•
A lithium battery backs up the system parameters and programmed items in
the SRAM, in case the base copier's main switch is turned off.
•
A Rechargeable battery backs up the SAF memory (DRAM) for 1 hour.
Switches
Item Description
SW1 Switches the SRAM backup battery on/off.
SW2 Reset switch, to reboot the FCU board
SW3 Determines which firmware the machine boots from. If the switch is OFF, the
firmware on the FCU inside the machine is used. If the switch is ON, the firmware
on the flash memory card or external FCU is used.