7-2
Section
Using Message Communications
92
The source words (starting with S) provide execution parameter and the com-
mand data as shown in the following table.
Word
Contents
S
Address of first word containing response
S+1
(See Specifying the Leading Address of the Response Words on page 93.)
S+2
Response monitoring time (hex)
0000:
2 s
1000 to 028F:
0.1 to 65.5 s (units of 0.1 s)
Above 028F:
65.5 s
S+3
Number of command bytes (hex)
0000 to 00F8: 0 to 248 bytes
S+4
.
.
.
Command data beginning with command code
The destination information provides the unit number of the destination Unit and
the number of words to be written, as shown in the following diagram.
Word
Contents
D
Unit number of the destination Unit (0000 to 000F hex = 0 to 15)
D+1
Number of words to write (0001 to 0080 hex = 1 to 128)
Reference 1. When sending explicit messages, set the response monitoring time in S+2
to 0014 Hex (2 seconds) or higher. If a shorter time is set, communications
may still be busy when the next command is sent after a timeout occurs.
2. The maximum number of bytes that can be transferred (shown above) is the
maximum number of bytes allowed with IOWR in CS1-series PCs. The actu-
al number of bytes that can be sent or received depends upon the explicit
message.
IOWR Data Area Ranges for CS1-series PCs
The following tables shows the data areas that can be used for each parameter
of IOWR.
Area
C
S
D
CIO Area
CIO 0000 to CIO 6143
CIO 0000 to
CIO 6142
Work Area
W000 to W511
W000 to W510
Holding Bit Area
H000 to H511
H000 to H510
Auxiliary Bit Area
A000 to A959
A000 to A958
Timer Area
T0000 to T4095
T0000 to T4094
Counter Area
C0000 to C4095
C0000 to C4094
DM Area
D00000 to D32767
D00000 to
D32766
EM Area without bank
E00000 to E32767
E00000 to
E32766
EM Area with bank
En_00000 to En_32767
(n = 0 to C)
En_00000 to
En_32766
(n = 0 to C)
Indirect DM/EM
addresses in binary
@ D00000 to @ D32767
@ E00000 to @ E32767
@ En_00000 to @ En_32767
(n = 0 to C)
