Festo MTR-DCI-...IO Series, Описание

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B. Supplementary information
B-8
Festo P.BE-MTR-DCI-IO-EN en 1209d
Note
Transmission of the command is repeated 8 times by the
host. After that the serial connection is regarded as unus-
able and is interrupted. Transmission must then be initial-
ized again.
B.1.2 CI commands
Caution
Loss of data
The Command Interpreter (CI) contains commands which
reorganise or delete parts of the memory. Existing data are
therefore destroyed:
•
Use preferably the FCT or the control panel for commis-
sioning and parametrizing.
•
Use the CI commands only in special applications which
require direct access to the controller.
•
Use CI commands only if you already know their effects
and if they are permitted for your MTR-DCI.
Access procedure The higher-order controller sends the controller either a write
command (WRITE) to modify a parameter in the object direc-
tory, or a read command (READ) to read out a parameter.
For each command the higher-order controller receives a
response which either contains the value read or, in the case
of a write command, serves as an acknowledgement. The
transmitted value (1, 2 or 4 data bytes) depends on the data
type of the object to be read or written.
WRITE (W) Write commands (W) transfer a value in the specified format
to the MTR-DCI. As a reply, write commands will be reflected
exactly character by character from the controller of the
MTR-DCI. A checksum <PS> will be inserted in front of the <CR>.