Murata DNT24 Series Скачать руководство пользователя

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15. Set the link drop threshold on the base by setting the

LinkDropThreshold

in Bank 1. This parameter sets the num-

ber of sequential hops without receiving a beacon that will trigger a child to
resynchronize and re-link to its parent. The default is 10 hops.

16. Set the point-to-point reply timeout on the base in the

P2PReplyTimeout

parameter in Bank 1. The default is 16

hops. See Section 7.4.2 for parameter details.

17. Configure the registration timeout on the base by setting the

RegistryTimeout

parameter in Bank 1. The default

timeout is 50 hops. See Section 7.4.2 for a discussion of this parameter.

18. Load an optional “friendly description” in each system radio in the

UserTag

parameter, Bank 0.

4.5 Configuring a Store-and-Forward System

The following additional parameters must be set to configure a DNT24 store-and-forward system:

1. Configure the DNT24 radios designated to be routers by setting the

DeviceMode

parameter

in Bank 0 to 0x02.

2. Enable store-and-forward operation on

all

system radios by setting the

Store&ForwardEn

parameter in Bank 0 to 0x01.

3. In each router, load a unique base-mode network ID into the

BaseModeNetID

parameter in Bank 0, and into the

base if a router is set to 0x00.

4. To configure a specific system topology, set the parent network ID parameter,

ParentNwkID,

and optionally the al-

ternate parent network ID parameter,

AltParentNwkID

, in all routers and

remotes. Note that a store-and-forward system topology can be formed either automatically or manually, based
on the settings of the

ParentNetworkID

and optionally the

AltParentNwkID

parameters:

- Setting the

ParentNwkID

parameter to 0xFF in all routers and remotes allows each router and remote to

automatically link to a parent, causing the system to form
automatically (child routers picking each other as a parent cannot occur). In this case, the

AltParent-

NwkID

parameter should be set to 0xFF, which disables it.

- Setting the

ParentNwkID

and optionally the

AltParentNwkID

parameters

to specific values in each router

and remote allows full manual control of the network topology.

The benefit of automatic system formation is self-healing. If a parent router fails, its child nodes can re-
link to any other parent router they can receive. However, automatic topology formation can result in an unnecessary
number of hops between routers or remotes and the base. The benefit of manual system topology formation is to avoid
unnecessary extra hops in the system, and to balance the number of children supported by each parent router. If a parent
router fails and an active alternate parent network ID has not been assigned, all children downstream from the failure will
be off the system until the failed router is repaired or replaced.

4.6 Slot Buffer Sizes, Number of Slots, Messages per Hop and Hop Duration

The

base slot size

(BSS) sets the maximum number of payload bytes the base can transmit during a single hop when the

base is sending

one

message per hop.

The maximum BSS is 105 bytes when a DNT24 system is configured for

one

slot.

Adding additional slots reduces the maximum BSS by three bytes per slot

The BSS