38/176 SLK memory structure
Bosch Rexroth AG
, MIT: ID 40, 3 842 530 344/2014-05
The actual link state can change in one of two ways:
• Due to a commanded link state from the application (see Chapter 5.3.2
“Commanded link state”)
• Automatically by the SLK, e.g., when an MDT signs on
The actual link state can only be read. Write access to this parameter returns an
error message, since the value of the actual link state can only be altered by the SLK
itself.
5.3.2
Commanded link state
The application controls the SLK through write access to the commanded link
state. This means, for example, that the SLK can be made ready for MDT sign-on or
terminate currently active communication with an MDT.
Table 10: Commanded link state
Action
Code
Description
CONNECT
1
Makes the SLK ready for MDT sign-on. The HF field is turned on.
DISCONNECT
2
Closes the MDT, i.e., the current communication with the MDT is
terminated, the MDT and the field are turned off. No other MDTs
can sign on to the SLK.
RECONNECT
3
Closes the MDT, i.e., the current communication with the MDT is
terminated, the MDT is turned off. However, the SLK remains ready
to receive data, the field is not turned off. The next MDT will sign
on to the SLK.
ERROR
4
The SLK has gone into the ERROR state, the field is off. No other
MDTs can sign on to the SLK. The current communication with the
MDT is first terminated, and the MDT signs off.
The term “request” means the actual link state does not always have to fulfill the
request to switch immediately.
Example: After the CONNECT request, the SLK is only “connected” when an MDT
enters the SLK field. Only then will the actual link state change to
CONNECTED
.
It is strongly recommended to check whether or not the system has implemented
the expected state following a commanded link state to the actual link state. Only
then can another commanded link state be made.
5.3.3
Auto mode
The auto mode function automatically terminates the MDT connection after
executing the prefetch. See Chapter 6.7 “Auto reconnect function” and Chapter 6.8
“Auto disconnect function”. Auto mode is inactive by default, the value is zero in the
auto mode register.
Entering a value of one immediately activates
auto reconnect
. All MDTs signing on to
the SLK will now run through the
PRECONNECTED
state and are then completed. The
connection switches to the
CONNECTING
state (display shows “wai”), i.e., the HF
field is active and the SLK can communicate with other MDTs.
Entering a value of two immediately activates
auto disconnect
. All MDTs signing on
to the SLK will now run through the
PRECONNECTED
state and are then completed.
PROOF COPy 1 | 20.05.2014 | FOR INTERNAL USE ONLy
