Mitsubishi MELSEC-A A2USHCPU-S1 User Manual page 96

4. CPU MODULE
(Continued)
Function (application)
Sampling trace
Performs chronological
checking on the behavior
status of devices set up when
debugging or an abnormal
behavior is detected.
Step operation
Checks conditions of program
execution and behavior during
debugging, etc.
Clock
Program control by clock data/
external display of clock data
Priority order of LED indication
Changing priority order of
display/canceling display
Self-diagnostics function
•An abnormal behavior of the
CPU module
•Preventive maintenance
Description
• With respect to a device for which the sampling trace is
set up, the operating condition of the device is sampled
for the number of times specified per scan or per period,
and the results are stored in the extension file register for
the sampling trace of the CPU main module. (the data
stored are cleared by the latch clear operation)
• Sampling trace is performed by the STRA instruction in
the sequence program.
• Executes operations of the sequence program with one
of the conditions (1) to (5) given below, then stops.
(1) Executes by each instruction.
(2) Executes by each circuit block.
(3) Executes by the step intervals and the number of
loops.
(4) Executes by the loop count and break points.
(5) Executes when the device values concur.
• Executes operation of the clock with the built-in CPU
module.
• Clock data: year, month, day , hour, minute, second, day
of the week
• When the clock data read request (M9028) is ON, the
clock data are read out and stored in D9025 to D9028 by
the clock element after the END processing of the
sequence operation.
• Executes operation of the clock with the built-in CPU
main module.
• For ERROR LED indication except for operation stop,
changing order of indication/canceling display are
executed.
• When an error that matches one of the self-diagnosis
items is generated at the CPU module power on or during
RUN, it prevents malfunctions by stopping the CPU
module operation and indicating the error.
• Stores the error codes corresponding to the self-
diagnostics item.
4 - 43
Overview of setting and operation
• Using the peripheral devices, set
the device to which the status
latch is performed and the
extension file register where the
data will be stored.
• Using the peripheral devices,
monitor the result of the sampling
trace.
• Selects a step operation condition
for the peripheral device and
executes.
• Sets data for D9025 to D9028 by a
peripheral device, turns M9025
ON, then write to the clock
element.
• Writes to the clock element by the
sequence program. (Dedicated
instructions can be used.)
• Writes data as to whether change
order/cancel indication to D9038
or D9039 by the sequence
program.
• There are some self-diagnostics
items with which the operation can
be continued or stopped by the
setting of peripheral device
parameters.
• Reads out the error codes with the
peripheral device and performs
troubleshooting.
(Refer to Section 4.1.4)