Sampling Trace - Mitsubishi L02CPU User Manual

3.20

Sampling Trace

This function samples the data of the specified device at a preset timing and at a preset interval (sampling cycle), and
then stores the trace results in the sampling trace file. In addition, this function can be used to read the device data
upon trigger condition establishment. This function is useful to check the change of the device data used in the
program during debugging at a preset timing.
To collect device data of 50 points or more, use the data logging function. For the data logging function, refer to the
following.
MELSEC-L CPU Module User's Manual (Data Logging Function)
(1) Sampling trace file
This file stores the trace setting necessary for executing the function and trace results. Sampling trace file can be
stored only in the Standard RAM.
(2) Devices that the sampling trace function is applicable
The following devices can be set up to 50 points.
Type
Bit device:
Word device:
The following modifications are available for the above devices.
• Digit specification of bit device
• Bit specification of word device
• Index modification
(3) Sampling trace operation
(a) Operating of the CPU module
When a sampling trace trigger is issued, the CPU module executes traces for the preset number of times.
CPU module
Standard RAM
Specified device
data* 1
1
Device
2
area
3
4
File
register 5
area
6
n -1
n
When data are stored by n th times, the 1st
data are overwritten by the next write data.
*1 When the trigger is issued, the CPU module samples data for the preset number of times and latches the data in the
sampling trace area.
X (DX), Y (DY), M, L, F, SM, V, B, SB, T (contact), T (coil), ST (contact), ST (coil), C (contact), C (coil), FX, FY, BL \S
T (current value), ST (current value), C (current value), D, D (extended data register), SD, W, W (extended link register),
SW, R, Z, ZR, FD, U \G
Sampling trace area
1st data
Writes data to
2nd data
a programming
3rd data
tool.
4th data
5th data
6th data
(n -1) th data
n th data
CHAPTER 3 CPU MODULE FUNCTIONS
Description
Programming tool
Sampling trace area
1
Displays data
2
by the specified
3
number of times.
4
5
6
n -1
n
3
Sampling trace
data monitoring
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