Tektronix 2714, Руководство программиста

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Programming
2714 & 2715 Programmer Manual
6–45
Table 6–1: Variable Names
Name Description Remarks
BD%
Integer value associated with a
particular device name by
IBĆ
FIND(BDNAME$,BD%)
.
Other names can be used such as
MYDEV%
,
FRST.DEV%
,
A1%
, etc.
BDNAME$
String variable set to a device name
such as
TEK_SA
. The name is the
one used when you set up the
device with
IBCONF
.
Any string variable name can be
used such as
MYNAME$
,
DEVNAM$
,
DN$
, etc.
EVENT.CODE$
A string variable argument of
IBRD
containing the 2714 or 2715 event
code.
Any string variable name can be
used: (
MYNAME$
,
DEVNAM$
,
DN$
,
etc.)
IBCNT%
Integer variable updated by GPIB
system software after a read, write or
command: the number of bytes
transferred. This name is reserved.
IBERR%
Integer variable returned by GPIB
system software when error bit of
status word is set. Range: 0 to 7, or
10 to 16. See your GPIB manual for meanings
of
IBERR%
values. The name is
reserved.
IBSTA%
Integer variable updated by all GPIB
system software functions. Refer to Status Byte on page 5–11.
NUMBYT%
Integer argument of
DEBLK
which
indicates the number of bytes
converted.
Any integer variable name can be
used (
MYNUM%
,
INTEG%
, etc.).
RD$
String variable used with the
IBDR
function to contain the data returned
by the 2714 or 2715.
Other names can be used such as
RET.DAT$
,
MYDAT$
,
S1$
, etc.
WRT$
A string variable used with the
IBWRT
function to contain the data
to be sent to the 2714 or 2715.
Other names can be used such as
WRT.DAT$
,
MESSAGE$
,
B4$
, etc.
You may desire to dimension arrays or variables at the beginning of your
program, even though they are to be used later. For instance,
CUR%()
is the
integer array used for curve data in our demonstration program.
RD$
is a string
variable that we use as the destination for a variety of data transfers.
If memory size is not a limiting factor in your controller, you may wish to set up
the maximum size of
RD$
at the head of the program with a
SPACE$
command as
in this example:
DIM SHARED CUR%(512)
RD$ = SPACE$(<max anticipated size>)