Resetting The Trigger Model Configuration; Initiate The Trigger Model; Configure The Lxi Trigger Bus - VTI Instruments EX1000A User Manual

Example: This code block sets a timer interval of 50 ms.
vtex10xxA_set_trigger_timer(vi, 0.05);
The current timer interval is queried with the vtex10xxA_get_trigger_timer query.
The LXI alarm is configured using the vtex10xxA_self_test_init function
vtex10xxA_set_alarm_enable call can be performed, vtex10xxA_set_alarm_enable must be set
to false.
Normally, each acquisition sequence is initiated by a trigger initialize function. However, this
requirement can be circumvented through the use of init continuous mode. Specifically, init
continuous returns the trigger model to the entrance of the ARM layer without the requirement of a
new trigger initialize function. This allows for a specific acquisition sequence to be restarted
automatically. The enabling of init continuous mode is done with the vtex10xxA_set_init_cont
function. This function simply accepts a Boolean value indicating the enable status of init continuous
mode.
The current setting of init continuous mode is queried with the vtex10xxA_get_init_cont query.

Resetting the trigger model configuration

The vtex10xxA_reset_trigger_arm function is used to return all of the EX10xxA's trigger
configuration parameters to their default values. It is similar to the vtex10xxA_reset function,
except that only trigger configuration parameters are affected. These parameters and their reset
values are documented in Table 6-1.
NOTE The extensive flexibility of the trigger model system permits the creation of very specialized trigger
conditions, which is a powerful application tool. However, it also permits the creation of trigger
conditions that would be very difficult to satisfy in practice. For example, if edge conditions are
specified on multiple digital hardware channels, the edges must occur within 25 ns of each other to
be recognized as having occurred simultaneously. Similarly, the timer source should not be
combined with any digital hardware edge conditions.
I T
NITIATE THE RIGGER
A trigger initialize is performed with the vtex10xxA_init_imm function. Upon the receipt of this
function, the trigger model transitions out of the IDLE layer and begins waiting for the ARM event.
This function clears the FIFO reading memory and resets all limit indications.
Once the trigger model has transitioned out of the IDLE layer, most instrument configuration
controls are disabled. An acquisition can, however, be aborted at any time with the
vtex10xxA_abort function. An abort does not affect any stored acquisition data.
C LXI T
ONFIGURE THE
The primary use of the trigger bus is the transmission of high-speed signals for multiple-unit
triggering and synchronization. Accordingly, it can be used for input and output operations. Each
LXI Trigger Bus (VTB) 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_vtb_input query is used to obtain the measured digital level (0 or 1) of the
VTB 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 bus. Within the 8-bit field, the MSB corresponds to VTB channel 7 and the
LSB corresponds to VTB channel 0.
Example: This code block queries the state of the trigger bus and reports the level of bits 7, 4, and 0.
EX10xxA Programming
M
ODEL
B
RIGGER US
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