LG GLOFA-GM Series User Manual page 128

Chapter 7 Communication function
Output Data type
ERR BOOL
STATUS USINT
LENx
USINT
(x=1,2,3,4)
Remark
[Note 1] If '_Udata_RCV' is used for FNAM specifying frame name in RCV_MSG Function Block, all the data
received to the specified area in RD1 of RCV_MSG Function Block are saved irrelevantly to the frame list
downloaded to Cnet I/F module. In this case, LEN1 displays the number of received data. (savable up to
256 byte). This function is especially used to receive all the data prepared by the protocol which is hard to
write via Frame Editor. If '_Udata_RCV' is used, all the data to be received are received without frame
searching so it cannot be used with theother different receiving frames. Besides, several '_Udata_RCVs'
can't be used at the same time, so is available for one module.
3) Receiving flag (_RCVx_232[i], _RCVx_422[i])
If the frame agreed with the downloaded frame via Cnet I/F module is received, Cnet I/F module lets the flag 'ON'
indicating the receiving completed to inform user of the receiving status of the required data for program.
Differently from transmission, execution time of receiving Function Block can't be known because the receiving
point of time can't be decided in PLC program for receiving data. Receiving flag indicating receiving time of data
has a function to receive the required data as sorted out when various receiving frames are applied as registered.
The receiving flag displays 3 data of RS-232C/RS-422 channel data, frame entry number and slot number of
Cnet I/F module altogether. The receiving flag is turned 'ON' if the applicable data is received and turned 'OFF' if
the received frame is being read via RCV_MSG Function Block. [Table 7.4] describes the details of the receiving
flag.
Turned On when the Function Block is called but not executed successfully and
keeps On until re-called. If error occurs, error information is displayed on output
STATUS
If ERR is 1 as the result of execution of Function Block, error code is output by
identification code for the error. If ERR is vanished, STATUS is also vanished to 0.
For details of error codes, refer to [Table 7.4] Error codes in user defined Function
Block.
Outputs the received data length of the set segment in a unit of byte.
7-9
Description