(2) When error information is read
If an error occurs at data receiving, error code will be treated as one data packet. When CPU module reads the
packet of error information, error flag (t+2) goes on, and error information is displayed on the return code area of
s parameter. At this time, the number of read data is set to 0, and the values of last data are kept.
Figure 6.17 Receiving data area format (Free protocol)
« Note »
In case of error at data reading, previous data remain in receiving data area. Therefore, if a program which refers
to the data part of receiving data area directly is created, old data will be referred to when errors occur.
By the methods as below, users can check if receiving command is executed properly.
1) The completion flag (t+1) ON of t parameter or the error flag (t+2) is monitored.
2) Return code area is monitored.
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