1055
Network Instructions Section 3-25
If RECV(098) is executed for the serial port of the CPU Unit, a Serial Commu-
nications Board (CS Series only), or Serial Communications Unit, a command
is sent from the serial port to the host computer. The command is a FINS
message enclosed between a host link header and terminator. The FINS
command is a MEMORY AREA READ command (command code 0101) and
the host link header code is 0F hexadecimal.
A program must be created in the host computer to process the send com-
mand (the FINS command enclosed in the host link header and terminator).
If the destination serial port is in the local PLC, set the network address to 00
(local network) in C+1, set the node address to 00 (local PLC) in C+2, and set
the unit address to 00 (CPU Unit), E1 (Inner Board, CS Series only), or unit
number + 10 hexadecimal (Serial Port Unit).
Receiving Data from a Host Link Slave PLC Connected by Serial Gateway
The serial gateway function can be used to receive data from a PLC con-
nected as a host link Slave to a Serial Communications Board or Unit. In this
case, the source node address must be set to the host link unit number + 1.
Flags
The following table shows relevant bits and flags in the Auxiliary Area.
Serial cable
PLC
Host Link Slave
Set the source node address to the host
link unit number + 1 = S+1.
RECV
PLC
Data
Host link unit number: S
Name Label Operation
Error Flag ER ON if the serial port number specified in C+1 is not within
the range of 00 to 04.
ON if the Communications Port Enabled Flag is OFF for
the communications port number specified in C+3.
OFF in all other cases.
Name Address Operation
Communications
Port Enabled Flag
A20200 to
A20207
These flags are turned ON to indicate that net-
work instructions, including PMCR(260) may be
executed for the corresponding ports (00 to 07).
A flag is turned OFF when a network instruction
is being executed for the corresponding port and
turned ON again when the instruction is com-
pleted.
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