A Closer Look At Storing Programs - HP 9000 200 Series Manual

A Closer Look at Storing Programs
To write a program to a mass storage device, you will use either the SAVE or the STORE
statement. There is no "right" or "wrong" choice; your choice depends upon the kind of
file you want .
• STORE records an internal representation of the program in a PROG file. The
main advantage of a PROG file is a rapid retrieval rate .
• SAVEl records the actual text of the program in an ASCII file. The main advantage
of an ASCII file is that it can be read as data by a BASIC program or by LIF-
compatible
2
devices (such as other HP computers and terminals).
The following table gives a summary of the differences between SAVE and STORE.
Characteristic
SAVE STORE
File type created: ASCII PROG
Retrieved by: GET LOAD
Approximate storage speed: 900 bytes/s 13 000 bytes/s
3
Approximate retrieval speed: 300 bytes/s
4
14 000 bytes/s
3
Can file be read as data? Yes No
LIF -compatible file? Yes No
Arbitrary program segments Yes No
allowed?
Subprograms included? Yes Yes
Can use LOAD SUB to retrieve a No Yes
subprogram ?
Stores CSUBs correctly No
Yes
1
Using SAVE requires the EDIT binary.
2
LIF is the acronym for Logical Interchange Format, which is a disc format used by several HP divisions.
(Note that the first letter of the file name must be a letter; in addition, some LIF-compatible devices
restrict file names to upper-case letters and the decimal digits 0 through 9.)
3
The speeds for LOAD and STORE are approximate for an interleave factor of 1 on an HP 9836 internal
disc drive. Interleave factors greater than this will cause a corresponding decrease in speed.
4
The retrieval speed for GET is very data-dependent. On an HP 9836 with a clock rate of 8 MHz,
for instance, it can vary from 20 bytes/second to 600 bytes/second (and maybe beyond those limits)
according to the contents of the file and the syntax checking required to enter the lines into program
memory. See the "Efficient Use of the Computer's Resources" for a discussion of how to time various
computer operations.
Editing and Storing Programs 6-33