Sequential/Overlapped Commands; Query Response Timing - ILX Lightwave LDT-5900 Series User Manual

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C H A P T E R

Sequential/Overlapped Commands

All common commands for the LDT-5900 Series Temperature Controllers are
sequential and most device-dependent commands are executed after the
previous command is complete.
The *WAI (common command) is an example of a sequential command which
forces the next command to wait until the no-operation-pending flag is true. This is
essentially the same as waiting for the OPC flag to become true, because the no-
operations-pending flag is used to set the OPC flag (bit 0 of the Standard Event
Status Register).

Query Response Timing

Query responses are evaluated at the time the query request is parsed, and not at
the time the response message is sent. In most cases this does not create a
problem since the time between parsing a query and sending its response is
small.
However, due to latency of new measurements being available, we recommend
waiting at least one second after changing any sensor parameter or output
condition before querying temperature measurements, sensor measurements or
status. Likewise wait one second to turn the output on after changing any sensor
parameter.
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R E M O T E O P E R A T I O N S
Remot e Comm unica t ion