Configure The Digital I/O System - VTI Instruments EX1000A User Manual

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Conversely, disabling manual limit control on a channel that had been enabled will automatically
set the limit set 0 values for that channel, based on its current EU conversion and units selection.
The current manual entry control and limit set 0 values for any channel are queried with the
vtex10xxA_get_limit_set0_manual and vtex10xxA_get_limit_set0 queries, respectively.
In contrast, limit set 1 operates in manual mode only. A channel's limit set 1 values are set with the
vtex10xxA_set_limit_set1 function. A channel's limit values can be set regardless of its inclusion
in the scan list, and multiple channels can be assigned to the same limit values within one function.
However, each unique combination of limit values must be set with a separate function.
The current limit set 1 values for any channel are queried with the vtex10xxA_get_limit_set1 query.
NOTE Limit sets operating in manual mode do not automatically adjust for changes in EU conversion or
units selection. For proper operation, limit values should be set after EU conversion and units
selections are made and reset upon subsequent configuration changes.
Once an acquisition has been completed, the vtex10xxA_get_accum_limit_status query is used to
obtain the accumulated limit status of all 48 channels. The response to this query is four arrays of
48 Boolean values each. The four arrays correspond to the set 0 lower limit, set 0 upper limit, set 1
lower limit, and set 1 upper limit, respectively. The returned values represent, on a per channel basis,
any excursion of the measurement data over their respective limits since the last trigger initialize.
Specifically, a returned "1" indicates that the limit was exceeded, while a returned "0" indicates that
it was not. As implied, limit status is cleared as part of the vtex10xxA_init_imm function. Limit
status is returned for all channels, regardless of their inclusion in the scan list. The limit status for
unscanned channels is always 0.
C D
ONFIGURE THE IGITAL
The digital I/O port on the EX10xxA can be used for input and output operations. Each DIO channel
can be independently programmed with regards to its output functionality, its static level to assume
when enabled as an output, and pulse operation.
The vtex10xxA_get_dio_input query is used to obtain the measured digital level (0 or 1) of the
DIO channels. The input monitoring functionality operates regardless of the simultaneous use of the
channels as outputs. The response to this query is a decimal value from 0 to 255 that represents the
8-bit value of the port. Within the 8-bit field, the MSB corresponds to DIO channel 7 and the LSB
corresponds to DIO channel 0.
104
ViInt32 e_channels[5] = { 0, 1, 2, 3, 4 };
vtex10xxA_set_limit_set0_manual(vi, e_channels, 5, 1);
vtex10xxA_set_limit_set0(vi, e_channels, 5, 0, 100);
I/O S
YSTEM
EX10xxA Programming