Filter
Top Products
Chapter 2 Formatting and I/O Library
© National Instruments Corporation 2-45 LabWindows/CVI Standard Libraries
short int instr_buf[100];
short int prog_buf[100];
status = ibrd (ud, instr_buf, 200);
Scan (instr_buf, "%100d[b2o01]>%100d", prog_buf);
If, instead, your GPIB instrument sends two-byte binary data in Motorola byte order,
the
Scan
function should appear as follows.
Scan (instr_buf, "%100d[b2o10]>%100d", prog_buf);
In either case, the
o
modifier is used only on the buffer containing the raw data from
the instrument (
instr_buf
). LabWindows/CVI will ensure that the program buffer
(
prog_buf
) is in the proper byte order for the host processor.
Note: When using both the
bn
and
on
modifiers on an integer specifier, the
bn
modifier
must be first.
Scanning Floating-Point Modifiers (%f)
bn
Specify Length. The
b
floating-point modifier specifies the length of the
floating-point argument, or the length of an individual array element, in bytes. The
default length is 8 B; therefore, double-precision values do not need this modifier.
Single-precision floating-point values are indicated by
b4
. 8 and 4 are the only valid
values for
n
.
in
Specify Array Offset. You can use the
i
floating-point modifier to specify an offset
within a floating-point array argument. It indicates the location within the array
where processing is to begin.
n
is the zero-based index of the first element to process.
Thus,
%10f[i2]
applied to a source floating-point array reads the 10 floating-point
values from the third through the twelfth elements of the array. The
i
modifier is
valid only if
rep
is present. If you use the
i
modifier with the
z
modifier, then
n
is
in terms of bytes.
z
Treat String as Floating Point. The
z
floating-point modifier indicates that the data
type of the corresponding argument is a string. Nevertheless, the data in the string is
treated as a floating-point array. The
z
modifier is valid only if
rep
is present.
wn
Specify String Size. The
w
floating-point modifier specifies the exact number of
bytes occupied by a string representation of the floating-point argument, in the event
that the value is converted from a string format. You can enter any non-negative
value here. If
n
is less than the number of digits required to represent the
floating-point number, an asterisk (
*
) will be inserted into the string to signify an
overflow. The default for
n
is zero, which indicates that the value can occupy
whatever space is necessary.
pn
Specify Precision. The
p
floating-point modifier specifies the number of digits to the
right of the decimal point in a string representation of the floating-point number.
Significant digits may be lost in attempting to conform to the precision specification.