CONTREX CX-1200 - Manual (Page 287)

7 - 48
FUNCTION (11) PARAMETER TRACE ENABLE/DISABLE
This function is used to setup and control the CX-1200 internal data collection feature: "Data Trace".
CX-1200 internal data collection feature
The CX-1200 control has the capability to record 1 millisecond samples of up to 4 monitor parameters. The
total size is 8192 samples (data points). The number of "Traces" (monitor parameters sampled) may be 1
(single trace), 2 (dual trace), or 4 (quad trace). The number of samples collected per trace are listed below:
Number of Samples per Trace
# of Trace Parameters Description Samples per Trace Parameter Total Sample Time
1 Single Trace 8192 8.192 Sec
2 Dual Trace 4096 4.096 Sec
4 Quad Trace 2048 2.048 Sec
Configuration:
For a single trace, set the value for Trace Parameter 1 to the desired monitor parameter number, and
set the rest of the Trace Parameters to zero (0).
For a dual trace, set the values for Trace Parameter 1 and 2 to the desired monitor parameter num-
bers, and set the rest of the Trace Parameters to zero (0).
For a quad trace, set all of the values for Trace Parameters 1 thru 4 to the desired monitor parameter
numbers.
Trigger:
The trace sampling begins when a "trigger" is encountered, after the "data trace" has been enabled.
The trigger is signaled through the PLC program by the "start trace" bit (167) transition from 0 to 1.
The CX-1200 control has the capability to collect "pre-trigger" data samples. These are samples
collected prior to a "trigger". The "pre-trigger time" is variable from 0 seconds to 2.000 seconds, and
is setup by the pre-trigger time (Pre-Trig) value and resolution in a "Set Trace Configuration" mes-
sage (defined later in this section).
Actions taken by the CX-1200 control in response to this function (11) are controlled by a "message control
byte" defined below.
Control Byte Definitions:
Bit 7 = Not Used (always 0)
Bit 6 = Not Used (always 0)
Bit 5 = Not Used (always 0)
Bit 4 = Not Used (always 0)
Bit 3 = Not Used (always 0)
Bit 2 = (1) Set Trace configuration (Pre-Trigger setting, and all Trace Parameter numbers)
Bit 1 = (1) Read Data Trace configuration (Pre-Trigger setting, and all Trace Parameter numbers)
Bit 0 = (1) Enable the Data Trace collection and wait for a trigger point (0) Disable the Trace
collection "stop"