VTI Instruments EX1629, Руководство пользователя

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VTI Instruments Corp.
150 EX1629 Command Set
vtex1629_get_dio_output
F
UNCTION
P
ROTOTYPE
ViStatus vtex1629_get_dio_output (ViSession vi , ViPInt32 dioOut );
F
UNCTION
P
ARAMETERS
vi = contains a session handle to the instrument. This handle is obtained by the function and remains valid until the
session is closed.
dioOut = an integer return value indicating the output state of the digital I/O. See the Description below for more
information concerning this parameter. Valid return values: 0 to 65535.
D
ATA
I
TEM
R
ESET
V
ALUE
Not applicable to this function.
D
ESCRIPTION
This function queries and returns the current programmed output state of both banks of the digital I/O. The dioOut
parameter is a decimal value that must be converted to a 16-bit binary value. Once done, the eight most significant
bits correspond to the eight channels of bank one (channels 8-15). The eight least significant bits correspond to the
eight channels of bank zero (channels 0-7). This is illustrated below.
bank one
channel #
bank zero
dioOut
15
0
14
0
13
0
12
0
11
0
10
0
9
0
8
0
7
0
6
0
5
0
4
0
3
0
2
0
1
0
0
0
The upper 16-bits will always be zero.
For example, a user queries the output state and the following was returned:
dioOut = 49164 → 0x0000C00C → 11000000 00001100
This indicates that channels 2 and 3 of digital I/O bank zero and channels 14 and 15 of digital I/O bank one are
configured high, while the remaining channels are low.
E
XAMPLE
ViSession instrumentHandle;
ViStatus status;
ViInt32 dio_out;
…
status = vtex1629_get_dio_output(instrumentHandle, &dio_out);