Siemens SIMATIC CP 440, Руководство пользователя

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Diagnostics with the CP 440
8-2
Point-to-point connection CP 440 Installation and Parameter Assignment
A5E00057742-02
8.1 Diagnostic functions of the CP 440
The diagnostic functions of the CP 440 enable you to quickly localize any errors
which occur. The following diagnostic options are available:
•
Diagnosis via the display elements of the CP 440
•
Diagnosis via the STATUS output of the function blocks
•
Diagnosis via the diagnostic buffer of the CP 440
Display Elements (LEDs)
The LEDs show the operating mode or possible error states of the CP 440. The
LEDs give you an initial overview of any internal or external errors as well as
interface-specific errors (see Chapter 8.2).
The special LEDs, TXD and RXD give you information on the state of the send
and receive lines. If you can’t establish a connection to a partner, refer to
Section 3.2 for help.
Section 5.5 contains information on LEDs that are activated when you download
firmware updates.
STATUS Output of the FBs
The function blocks FB SEND_440, FB RECV_440 and RES_RECV have a
STATUS output to indicate an error diagnosis. Reading the STATUS output of the
function blocks gives you information on errors which have occurred during
communication. You can evaluate the STATUS parameter in the user program (see
Section 8.3).
The CP 440 also enters the diagnostic events at the STATUS output in its
diagnostic buffer.
Diagnostic Buffer of the CP 440
All the CP 440’s errors are entered in its diagnostic buffer.
In the same way as with the diagnostic buffer of the CPU, you can also display on
the programming device the plain-text, user-relevant information of the CP
diagnostic buffer about the information functions of STEP 7 (see Section 8.4).