Define/Control Autonomous Host Streams (Command 'C') - Pressure Systems 9046 User Manual

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5.7 Define/Control Autonomous Host Streams (Command 'c')

Purpose : Defines and controls the autonomous delivery of up to three concurrent high-speed
autonomous data streams to the host computer. Such data streams may be delivered
"continuously" (i.e., unbounded, until a command explicitly stops them), or be delivered in a
"limited" amount (i.e., bounded, by a pre-specified fixed number of data scans to be sent). Each
scan delivered may be synchronized by a user-supplied "hardware trigger" or each scan may
be delivered periodically as synchronized by an internal software clock. These concurrent host
streams are an alternate method of acquiring/delivering data rather than the host using the
many other special purpose "read" commands (' V ', 'a ', ' b ', ' r ', ' t ', ' m ', and ' n ') for reading various
data values in various formats.
Host data streams, once activated in a module, normally deliver a sequence of TCP/IP
(optionally UDP/IP) data scans autonomously to the host (i.e., without the host sending any
particular command to the module to request each scan).
Note
Various sub-commands (described on the following pages) are used to identify the various
definition and control options of the following general 'c' command.
Command "c ii[ dddd] ... "
'c' is the operation code
' ii' is a space followed by a sub-command index
(augment code).
' dddd' are one or more optional datum fields, each
preceded by a space character; These
parameters differ for each sub-command.
NOTE: all parameters are preceded by a space,
including the first hex parameter (ii) - which is
unlike most other commands which attach the first
parameter(s) to the operation code.
Response Depends upon particular sub-command (' ii') sent.
See below.
Autonomous Depends upon the particular sub-command (' ii')
Packet sent. See below.
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If data streams are defined to occur at high scan rates, then each
data scan received by the host must be processed and disposed of
in a timely manner. Model 9046 modules are capable of generating
autonomous data streams faster than some "slow" hosts (or limited
software, including NUSS) can absorb.
Model 9046 User's Manual
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