HP 5100 Service Manual - Page 82

Note Note Note Printer memory Memory is delivered on a single DIMM, which occupies one of the four slots available. This leaves three DIMM slots that may be used to add memory, fonts, or firmware upgrades. The memory that comes with the printer is on one of two types of combination Flash/DRAM DIMMs. The HP LaserJet 5100 and HP LaserJet 5100Le printers use a 4 MB Flash/ROM and 16 MB SDRAM version; the HP LaserJet 5100tn and HP LaserJet 5100dtn printers use a 4MB Flash/ROM and 32 MB SDRAM version. DIMMs and SIMMS are not compatible. Only one type of DRAM DIMM is supported-SDRAM DIMMs that are 32-bit, 100-pin, 100 MHz (PC100). Read-only memory and random-access memory (RAM) Besides storing microprocessor control programs, the read-only memory (ROM) stores dot patterns of internal character sets (fonts). Early versions of the printer might contain downloadable flash rather than ROM to store the processor code (firmware). The random-access memory (RAM) contains the page and I/O buffers and the font storage area. It stores printing and font information that is received from the host system, and can also serve to temporarily store a full page of print-image data before the data is sent to the print engine (see "Page protect" on page 81). RAM memory capacities for each printer are shown in on page 16. Memory capacity can be increased by adding DIMMs to the formatter PCA. Note that adding memory (DIMMs) might also increase the print speed for complex graphics. If the printer encounters difficulty managing available memory, a clearable warning message appears on the control panel. Some printer messages are affected by the auto continue and clearable warning settings from the configuration menu in the printer control panel. If CLEARABLE WARNING=JOB is set on the control panel, warning messages appear on the control panel until the end of the job from which they were generated. If CLEARABLE WARNING=ON is set, warning messages appear on the control panel until [GO] is pressed. If an error occurs that prevents normal printing and AUTO CONTINUE=ON is set, the printer goes offline for 10 seconds before it returns online. If AUTO CONTINUE=OFF is set, the message appears until [GO] is pressed. Nonvolatile random-access memory The printer uses nonvolatile random-access memory (NVRAM) to store I/O and information about printer configuration. The contents of NVRAM are retained when the printer is turned off or disconnected. Memory Enhancement technology The HP Memory Enhancement technology (MEt) effectively doubles the memory capacity through a variety of font- and data-compression methods. MEt is only available in PCL mode; it is not functional in PS mode. 80 Functional information Q1860-90918