Technical data

8-14
Preset State and Memory Allocation
Memory Allocation
The analyzer attempts to allocate memory at the start of a calibration. If insufficient memory is available,
an error message is displayed. It is possible that the CMOS memory might be fragmented due to the
sequence of saving and deleting states of various sizes. So another alternative would be to store the current
state to disk and then press Preset. The analyzer runs a memory packer which might regain some
previously inaccessible memory. If memory is still inadequate, delete an instrument state and restart the
calibration.
Storing Data to Disk
You can use the internal disk drive or connect an external disk drive for storage of instrument states,
calibration data, measurement data, and plot files. (Refer to user’s guide for more information on saving
measurement data and plot files.)
The analyzer displays one file name per stored instrument state when you list the disk directory. In reality,
several files are actually stored to the disk when you store the instrument state. Thus, when the disk
directory is accessed from a remote system controller, the directory will show several files associated with
a particular saved state. The maximum number of files that you can store on a disk depends on the
directory size. You can define the directory size when you format a disk. For the default directory size for
floppy disks and hard disks, refer to Table 8-1.
The maximum number of instrument states and calibrations that can reside on a disk is limited by the
available disk space. To see the available disk space displayed on the analyzer, press Save/Recall. (Be sure
you have selected either INTERNAL DISK, or EXTERNAL DISK, depending on your disk type.) In the
upper right-hand portion of the display, the value displayed as Bytes free: is the available disk space. If
your disk is formatted in LIF, this value is the largest contiguous block of disk space. Since the analyzer is
reporting the largest contiguous block of disk space, you may or may not see the bytes free number change
when you delete files. If your disk is formatted in DOS, the number reported as bytes free is the total
available disk space. That number is updated whenever you save to or delete files from the disk.
A disk file created by the analyzer appends a suffix to the file name. (This is on the analyzer's directory and
is not visible.) The suffix consists of one or two characters: the first character is the file type and the
second is a data index. (Each suffix character is defined in Table 8-6.)
d. If the channels are coupled, this number is always 1. If the channels are uncoupled, this number refers to the number of
channels that have power meter cal on.
e. This value may change with different firmware revisions.