3-1SectionData Carrier Motion and Command Conditions
15
3-1-2 Command Reception Status
Command Wait Status This
is the condition in which
no command processing is being performed, and
the
ID Controller is ready to accept any command. Once a
command is received,
it enters the command processing status.
Commands received during the interval from when a command has been
accepted until a response indicating the command processing has been com-
pleted
has been returned, are ignored. However
, one exception during proces
-
sing
of auto read and auto write commands (see page
37 to
38) is that the auto
command processing’s abort command can be accepted.
Note This command processing status does not include the polling auto command.
This
refers to the situation when a polling auto command is
sent and the DC has
not
arrived in front of the specified R/W Head. In
this status, the specified R/W
Head
can only accept subcommands.
Subcommands are commands that query
the
wait status for approach of the DC at the R/W Head (see page
39 to
41). In
the polling auto subcommand wait status, commands can be sent to the other
R/W Head.
3-1-3 Read and Write Functions
The
read/write functions
are used for communications when the DC is station
-
ary.
Thus, before using these commands, it is necessary to check that the DC is
at a specific position. If the DC is not in
a specified position, an error response is
returned.
(Host
Computer)
(ID Controller)
(DC)
DC
DC
Not close
(stationary)
(stationary)
In motion
Response
Read/Write
processing
Command
completed
Read/Write
Command
1, 2, 3...
1. Once
it is confirmed that the DC has stopped in the specified position, the
host computer sends the command.
2. The
ID Controller follows the command and performs read/write operations.
3. After processing has been completed, the ID Controller returns a proces-
sing
completed response to the host computer
. The host computer
accepts
the response and once again starts the line workpiece, with the DC
attached, in motion.
Command Processing
Status
Polling Auto Subcommand
Wait Status
Command Processing
During Read/Write
Operations