6F8C0904 107
6.4 Using the EN311 Socket Interface
6
(4) Methods for storing receive data
• The value specified as "number of received data words N" is the size of the transmitted
data in a single operation to the socket (number of words) + 1 word. The S controller
checks for register area with the value of N and returns error status:
Boundary error ••• 5060(16#EC3C)
• In this case, data is not transferred to the register area, and the data is discarded. The
data is not retained in the EN311 either.
• Allocate a reception data storage register area with a size equal to the size of the
reception data plus one word. The reception data count (the size of the transmission
data for a single operation) and the transmission data for a single operation will be
stored in this area as shown in the figure below.
(5) Important notes
• An error is returned if a receive request is issued for a socket that is not yet opened.
Error status: Unopened ••• 2945(16#B81)
• An error is returned if a socket identifier other than 1 to 8 is specified.
Error status: Invalid socket identifier ••• 2946(16#B82)
• It is not possible to receive data sent from the local node, even if the local node IP
address is specified at the transmission source IP address.
• Values in the range 1024 to 65535 can be specified as the object socket UDP port
number for the transmission source. An error will be returned if a value outside that
range is specified.
Error status: Port number error ••• 2929(16#B71)
• An error will be returned if a value of 0 words or 1001 or more words is specified as the
receive data size.
Error status: Transmission word count error ••• 5059(16#EC3D)
• An error will be returned if the reception timeout time is exceeded.
Error status: Timeout ••• 2848(16#B20)(0020H)
• If the size of data transmitted in a single operation > the number of data words
received (N-1), then the receive request will cause an error.
Error status: Receive request (number of words) error in the S controller •••
3009(16#BC1)
Only the reception data size of the received data from the beginning will be transferred
to the receive data storage register area of the S controller. The remaining data will not
be stored in the EN311 either.
• The EN311 uses a priority ordering in processing sockets 1 through 8. Therefore,
systems constructed so that socket 1 is activated frequently may not be able to
process socket 8, resulting in the following error response:
Error status: Send completion timeout UDP ••• 5002(16#EC76)
When constructing a system, take the socket utilization conditions into account when
allocating sockets.
Receive data size (bytes)
←
Head of the
specified register
Transmission data sent to the
Receive data storage
socket in a single operation register area
To Next Page
Loading...
