Siemens CP 243-1 IT, Technical Manual

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Programming 03/03
CP 243-1 IT
J31069-D0429-U001-A0-7618
96
5.1 ETHx_CTRL
The subprogram ETHx_CTRL initializes and monitors the CP 243-1 IT. You must
call this subprogram in your S7-200 user program at the beginning of every cycle if
you want to utilize the functions of a CP 243-1 IT. After a iser program or a new
configuration is downloaded by SETP 7 Micro/Win 32 to the S7-200 CPU and the
S7-200 CPU is started again, this subroutine commands the Cp 243-1 IT to check
for changes in the configuration data. If the CRC checking is enabled the CP243-1
IT will only restart if a new configuraton is detected. If the CRC checking is dis-
abled then the CP 243-1 It will always restart.
The return values contain information on the general state of the CP 243-1 IT, the
state of up to eight possible S7 communication channels and the state of the IT
services.
When an error occurs on the CP 243-1 IT, you can read out the error or message
code with the Error return parameter. This code is available for a maximum of 60
seconds. The CP 243-1 IT assumes that, during this time, the S7-200 user pro-
gram has evaluated the error or message code and sets the Error return parameter
back to 0 after 60 seconds. This routine prevents outdated error or message codes
of the CP 243-1 IT from being returned via the Error parameter for a long period of
time.
The subprogram ETHx_CTRL is always created by the Internet wizard of STEP 7
Micro/WIN 32 as soon as the configuration CP 243-1 IT is concluded.
Call:
ETHx_CTRL
EN
CH_Ready
ERR
CP_Ready CP_READY
CH_READY
Error
Always_On
Fig. 9 Calling the subprogram ETHx_CTRL
Input parameters:
Name Type Meaning
- - -
Table 17 Input parameters (ETHx_CTRL)