User Guide

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System Operation
Transmitters and receivers are paired using the built-in Join Process (see
the Join Process for details). One device is configured as an Administrator
and creates the network address and encryption key. When Nodes join,
the Administrator sends them the encryption key, network address and
their unique address within the network. The addressing method used by
the HumPRC
TM
Series modules can support up to hundreds of nodes,
depending on the use model (duration of activations and how often they
are sent).
It is up to the designer to determine which device makes the most sense
as the Administrator in the final system, but there are some common
configurations. In a system with one transmitter and one receiver, it does
not matter which is the Administrator. In a system where one transmitter
is going to activate several receivers, the transmitter is normally the
Administrator (Figure 21 a). In a system with one receiver and multiple
transmitters, the receiver is normally the Administrator (Figure 21 b).
A system with multiple transmitters and receivers can use any of the
devices as an Administrator (Figure 22 a) or may use a separate device
that is only used to join new devices to the network (Figure 22 b). Once all
system nodes have received the key and their address, the Administrator
node operates the same as any other node.
By default, the Administrator and all Nodes broadcast to the entire network.
All transmitters can activate all receivers in the network. An external
microcontroller can be used to change the UDESTID0 register to activate
a specific Node in the network. This is a more advanced operation and
requires the microcontroller and custom firmware.
Reading the Transmitter Address
The HumPRC
TM
Series modules do not require any software for basic
operation. There is no compiler to get, no code to write and download into
the module. However, the built-in Command Data Interface (CDI) can be
used to add additional or advanced functionality to a system.
One such feature is the ability to read out of the receiver the identity of the
transmitter that sent the commands. This allows an external processor to
log access attempts or set additional controls over which transmitters are
allowed to activate the product outside of the module.
By default, the module automatically configures itself to respond to the
transmitting module (AUTOADDR = 0x07). This configuration takes the
source address from the received packet and writes it to the UDESTID
registers UDESTID[0-3]. Reading these registers after a valid transmission
has been received indicates the transmitter that sent the command.
Administrator
Administrator
Figure 21: HumPRC
TM
Series Transceiver Transmitter to Receiver Ratios
a b
Administrator
Figure 22: HumPRC
TM
Series Transceiver Multiple TX and RX
a b