Printer Ram And Printer Capabilities; Crc Life Counter Behavior - Xerox 2135DX - Phaser Color Laser Printer Service Manual

Printer RAM and printer capabilities

The printer features three DIMM connectors which accept 64-, 128-, and
256-Mbytes RAM DIMMs. The printer can use off-the-shelf RAM meeting these
specifications:
168-pin DIMM
Synchronous DRAM
3.3 volt
9 nsec speed
Valid on-board Serial Presence Detect ROM.
The Startup page and the Configuration Page list the amount of RAM installed in
the printer.
If the DIMM does not meets the system controller board's specifications, then the
printer reports an "Invalid Memory DIMM Configuration" message and stops the
booting process.
If the power-up self-test diagnostics detect a DIMM with defective memory cells
the printer declares "Diagnostics Failed - Press Enter to Continue." After the
enter key is pressed the boot process continues and the defective RAM DIMM is
ignored. Note that a seriously defective RAM DIMMs (with grounded address
lines, for example) can keep the system controller board from booting up at all.
With more memory the printer gains the capabilities of printing without having
to use image compression (which trades less installed RAM for longer image
processing time) and dual frame buffers for printing one image while processing
a second image (which gives greater printing throughput).
The printer features three slots each of which can contain a 64-, 128-, or
256-Mbytes SDRAM DIMM. Any slot may be used for any size DIMM. DRAM
memory totalling beyond 512 Mbytes will be ignored. For a capacity of
512 Mbytes, 256-Mbyte DRAM DIMMs cannot be mixed with 128-Mbyte RAM
DIMMs. The image-processing controller board also contains 16-kbytes of
non-volatile memory (NVRAM), to store all for the necessary values that can be
set on the printer.

CRC life counter behavior

Internal counters track customer replaceable consumable (CRC) life usage and
store the values in NVRAM. The controller monitors these counters in order to
display the near end-of-use and end-of-use messages.
The toner states displayed are OK, Low, and Empty, where the engine senses and
automatically reports the Low and Empty states. When the empty state is
reached for toner, the printer terminates printing at the end of current page and
displays the appropriate message on the control panel. No further jobs are
accepted from any input port. All printer CRCs wait for the current print job to
finish before declaring a Low or Empty state.
4 Phaser 2135 Color Printer