CS1D-CPU

Troubleshooting Problems with Unit Versions on the CX-Programmer
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Problem Cause Solution
After the above message is displayed, a compiling
error will be displayed on the Compile Tab Page in the
Output Window.
“????” is displayed in a program transferred from the
PLC to the CX-Programmer.
An attempt was made using CX-
Programmer version 4.0 or higher
to download a program containing
instructions supported only by
CPU Units Ver. 2.0 or later to a
Pre-Ver. 2.0 CPU Units.
An attempt was made using CX-
Programmer version 4.0 or higher
to download a PLC Setup containing
settings supported only by
CPU Units Ver. 2.0 or later (i.e.,
not set to their default values) to a
Pre-Ver. 2.0 CPU Units.
CX-Programmer version 3.3 or
lower was used to upload a program
containing instructions supported
only by CPU Units Ver. 2.0
or later from a CPU Unit Ver. 2.0
or later.
Check the program or change
the CPU Unit being downloaded
to a CPU Unit Ver. 2.0
or later.
Check the settings in the PLC
Setup or change the CPU Unit
being downloaded to a CPU
Unit Ver. 2.0 or later.
The new instructions cannot
be uploaded using CX-Programmer
version 3.3 or lower.
Use CX-Programmer version
4.0 or higher.