QMS 1725E, Reference

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Memory
5-9 Additional Technical Information
ROM (Read Only Memory)
ROM contains data and/or machine-executable instructions that can
be read but not modified. On your QMS 1725E Print System, the
operating system code, resident fonts, and resident emulations are
stored in ROM. This information is not lost when the printer’s power is
turned off.
RAM (Random Access Memory)
RAM is the memory your printer uses to perform each task. It can be
written to and read from. Once a task is complete, the memory is free
again to be used for another file. This memory is volatile, so if your
printer loses power while a file is being sent, the file must be resent.
The number and type of features you can run on your printer simulta-
neously depend on the amount of RAM you have and how that RAM
is distributed. Your printer comes with 8 MB of RAM, but it is upgrad-
able to 64 MB by adding Single In-line Memory Modules (SIMMs).
RAM Disk
Also called a virtual disk, the RAM disk is an area of RAM that is used
to simulate an additional hard disk. Data can be written and read
more quickly than on a hard disk, but a RAM disk loses any
information stored on it when the printer’s power is turned off. The
spooling buffer is a RAM disk client.
SCSI (Small Computer System Interface)
The printer’s SCSI port (located on the interface panel on the back of
the printer) allows you to connect up to three optional SCSI hard
disks, (four if there’s no internal hard disk installed), providing storage
for fonts, emulations, and other files. Hard disks are also used to
increase collation capacity and provide a secondary storage area for
spooled data, while providing virtual memory capabilities.
Volatile Memory
This type of memory is cleared when the printer is turned off. For
example, most RAM is volatile.