YASKAWA S-7 Series, Command Manual

Page: 40 / 191

2.1 Common Command Format
2-3
2
Command Format
2.1 Common Command Format
This section describes the specifications that are common for all commands.
The format that is common for the commands sent from the master station and the responses
returned from slave stations is shown below.
The format of a command can be divided into the main command area (32 bytes) and the sub-
command area (16 bytes). The subcommand area is used to supplement the main command
with another command. Whether the subcommand area is used or not is determined by the
setting of the number of transmission bytes. When the number of transmission bytes is 32, the
subcommand area is not used.
Both the main command area and subcommand area are divided into the command header
section and the command data section.
Fields in the command header section of the main command area
Fields in the command header section of the subcommand area
Command: CMD, WDT, CMD_CTRL
Response: RCMD, RWDT, CMD_STAT
Command: SUBCMD, SUB_CTRL
Response: RSUBCMD, SUB_STAT
Byte Command Response Description
Main
Command
Area
0 CMD RCMD
•
CMD/RCMD:
Command code specified for individual com-
mands. Refer to the following section.
2.2.1 Command Code (CMD/RCMD) on page
2-5.
•
WDT/RWDT: Refer to the following section.
2.2.2 Watchdog Data (WDT/RWDT) on page
2-6.
•
CMD_CTRL: Refer to the following section.
2.2.3 Command Control (CMD_CTRL) on
page 2-6.
•
CMD_STAT: Refer to the following section.
2.2.4 Command Status (CMD_STAT) on page
2-7.
•
CMD_DATA/RSP_DATA:
Specified for individual commands.
1 WDT RWDT
2
CMD_CTRL CMD_STAT
3
4
CMD_DATA RSP_DATA
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
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Continued on next page.