Siemens CP 243-1 IT, Техническое руководство

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03/03 Programming
CP 243-1 IT
J31069-D0429-U001-A0-7618
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Return parameters:
Name Type Meaning
Done BOOL Status of the subprogram call
0:
Subprogram not executed yet
1: Subprogram executed, ready for next
execution
Error BYTE Error code
16#00: No error
Other: Error (for a description, see chapter 6.2)
Table 20 Return parameters (ETHx_CFG)
5.3 ETHx_XFR
Calling the subprogram ETHx_XFR causes the CP 243-1 IT to transfer data to an-
other S7 system or to request data from such a system. The type of data access
which your CP 243-1 IT uses is specified by you in the configuration. This means
that you have already specified the following during configuration.
•
What data are to be accessed
•
Whether these data are to be read or written
•
The communication partner from which these data are obtained or to which
these data are transferred
When you call the subprogram ETHx_XFR, you specify which of the configured cli-
ent channels you want to use for which configured data accesses.
The subprogram ETHx_XFR is only created by the Internet wizard in STEP 7 Mi-
cro/WIN 32 if you have configured at least one of the channels of the CP 243-1 IT
as client. Only then can you trigger data accesses from a S7-200 user program via
a CP 243-1 IT.
Only one subprogram ETHx_XFR per channel can be active at a time. Since paral-
lel execution of several data accesses to one channel is impossible, we recom-
mend linking the input "START" with both the return value "Done" of the subpro-
gram ETHx_XFR and the applicable bit of the return value "CH_Ready" from the
subprogram ETHx_CTRL.