Yokogawa EJX930A - Manual (Page 131)

<Appendix 6. Link Master Functions>
A6-3
IM 01C25T02-01E
(2) In the LAS settings of the transmitter, set the values of V(ST), V(MRD), and V(MID) to the same as the
respective lowest capability values in all the devices within the segment. An example is shown below.
DlmeBasicInfo (Index 374 (SM))
Subindex Element EJX Device 1 Device 2 Device 3 Description
1 SlotTime 4 8 10 20 Capability value for V(ST)
3 MaxResponseDelay 3 6 3 5 Capability value for V(MRD)
6 MinInterPduDelay 4 8 12 10 Capability value for V(MID)
In this case, set SlotTime, MaxResponseTime, and MinInterPduDelay as follows:
ConfiguredLinkSettingsRecord (Index 385 (SM))
Subindex Element Setting (Default) Description
1 SlotTime 20 (4095) V (ST)
3 MaxResponseDelay 6 (5) V (MRD)
6 MinInterPduDelay 12 (12) V (MID)
(3) In the LAS settings of the transmitter, set the values of V(FUN) and V(NUN) so that they include the node
addresses of all nodes within the same segment. (See also Figure 3.)
ConfiguredLinkSettingsRecord (Index 385 (SM))
Subindex Element Default Value Description
4 FirstUnpolledNodeId 0x25 V (FUN)
7 NumConsecUnpolledNodeId 0xBA V (NUN)
A6.4 LM Functions
No. Function Description
1 LM initialization When a fieldbus segment starts, the LM with the smallest [V(ST) ×
V(TN)] value within the segment becomes the LAS.
At all times, each LM is checking whether or not a carrier is on the
segment.
2 Startup of other nodes (PN and Node
Activation SPDU transmissions)
Transmits a PN (Probe Node) message, and Node Activation SPDU
message to devices which return a new PR (Probe Response)
message.
3 PT transmission (including final bit
monitoring)
Passes a PT (Pass Token) message to devices included in the live list
sequentially, and monitors the RT (Return Token) and final bit returned in
reply to the PT.
4 CD transmission Transmits a CD (Compel Data) message at the scheduled times.
5 Time synchronization Supports periodic TD (Time Distribution) transmissions and
transmissions of a reply to a CT (Compel Time).
6 Domain download server Sets the schedule data.
The schedule data can be equalized only when the Domain Download
command is carried out from outside the LM in question.
(The version of the schedule is usually monitored, but no action takes
place, even when it changes.)
7 Live list equalization Transmits SPDU messages to LMs to equalize live lists.
8 LAS transfer Transfers the right of being the LAS to another LM.
9 Reading/writing of NMIB for LM See Section A6.5.
10 Round Trip Delay Reply (RR) Reply to
DLPDU
Not yet supported in the current version.
11 Long address Not yet supported in the current version.