Omron CQM1H-SCB41 Time Lag t1, Error Flags for Overrun, Framing, and Parity Errors

Using Protocol Macros			Section 5-7
Time Lag t1
	Baud rate (b/s)	Lag time (ms)
	1,200	30
	2,400	15
	4,800	8
	9,600	5
	19,200	3

Note The lag time shown above is an approximate value. It may become longer de- pending on the protocol macro processing.

Error Flags for Overrun, Framing, and Parity Errors

When an overrun, framing, or parity error is detected during a protocol macro, the receive data will be stored in the reception buffer along with error informa- tion. The error flags will operate as described next.

Receive Data with Error Information that Matches Expected Receive Mes- sages

The expected receive message received for the RECEIVE operation is found in the reception buffer and handled as receive data. If the receive data contains error information, the corresponding error flags are turned ON.

The following example shows reception of 100 bytes of data that matches an expected receive message.

100 bytes	Error flags ON
	Parity errors

Receive Data with Error Information that Does Not Match Expected Re- ceive Messages

If there is no expected receive message that matches the receive data, the data is discarded and the error flags are not affected. The trace information will con- tain any error information entering the reception buffer up to the capacity of the trace data.

The following example illustrated what happens when there is no expected re- ceive message that matches the receive data.

Discarded

Error flags are not changed.

In the following ladder programming, sequence number 000 (E5jK Digital Con- troller Read) is executed through PMCR(––) to read the PV from the Digital Con-

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