Programming instructions

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List of Used Devices
The List of Used Devices will show a list of the devices used in the program. The
list can be configured to show a single program (FX only supports one) or all
programs in the PLC (in the case of a Q-Series PLC). An address is entered in
the find device box, and after pressing the Execute button, the list starting at that
address is shown in the window below. There are columns which will show an
asterisk (*) if that address has been used as an input or output. Inputs include
source data for applied instructions and outputs include destinations of applied
instructions. The ERR column is marked if the address is used as either input or
output but not both. Depending on the addresses and their use in the program,
this is not necessarily and error.
14.8 Data Trace
GX Developer provides a troubleshooting tool called a trace. This tool allows the
programmer to graph the state of values in the PLC over time. This tool
executes a data trace within the PLC, so it is not limited by the communication
method in use to the PC.
The FX series supports a data trace of 512 samples. Samples can be based on
PLC scans or on an interval adjustable from 10ms to 2000ms in 10ms
increments. It can be triggered from the software or by the changing of a bit or
word value in the PLC. Samples can be recorded from before the trigger takes
place as well.
The data trace in the FX series can log up to 10 bit devices and 3 word devices.