Lake Shore 475, Руководство пользователя

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Lake Shore Model 475 Gaussmeter User’s Manual
5-8 Advanced Operation
5.5 TRIGGERING
A hardware, TTL level, trigger into the instrument can be used to initiate the data log sequence. A hardware, TTL level
trigger out of the instrument indicates when the instrument completes a reading and can be used to synchronize other
instruments in a system. A software, IEEE-488 based trigger can be used similar to the hardware trigger in. The
hardware trigger signals are located in the Auxiliary I/O connector, which is described in Paragraph 3.6. The timing of
the hardware trigger input and output are described in Figures 5-1 and 5-2.
The hardware trigger input is an edge sensitive, active low signal. To ensure that the trigger is detected by the
Model 475, it is recommended that the signal be held high for a minimum of 25 microseconds, and then held low for
another 25 microseconds before going high again.
The hardware trigger output is a 2 millisecond, active low, pulse. This signal is not available during the high speed
binary operation of the instrument (refer to Chapter 6 for high speed binary description).
Figure 5-1. Trigger Input Timing Diagram
Figure 5-2. Trigger Output Timing Diagram