User's Manual

5 Functional description

The Themisto-I can be conﬁgured to operate in several modes at the physical, MAC as well

as the network layer. This chapter describes all the available modes of operation.

5.1 Physical layer

At the physical layer, the Themisto-I can be conﬁgured to use one of the following radio pro-

ﬁles (see parameter

RADIO_DefaultRfProfile

Radio proﬁle Data rate (gross) [kcps] Modulation Max packet size [Byte]

6 400 GFSK 224

8 (long range mode) 480 (= 240 kbps net) DSSS with FEC 224

9 (long range mode) 480 (= 30 kbps net) DSSS with FEC 224

Additionally, the frequency channel of operation is conﬁgurable to avoid interference between

several subnets of radio devices (see

RADIO_DefaultRfChannel

). The radio parameters

need to be chosen for optimal performance based on the required range, data rate, maximum

payload size, keeping in mind the compliance with valid regulatory requirements. A detailed

description for conﬁguring these parameters could be found in chapter

and chapter

5.2 MAC and network layer

5.2.1 Addressing modes

In order to interconnect several modules and build a network or to send data to speciﬁc

devices, the Themisto-I supports addressing at MAC and network levels. Based on the

address mode of the module conﬁgured using the UserSetting

MAC_DefaultAddressMode

each device can be conﬁgured with an address (1 or 2 byte) and a network id (1 byte) that

is deﬁned by the UserSettings

MAC_SourceAddr

and

MAC_SourceNetID

respectively.

Address mode MAC address size [Byte] Network address size [Byte]

0 0 0

1 1 0

2 1 1

3 2 1

Depending on the selected address mode up to 254 network IDs and up to 65534 addresses

are supported. 0xFF and 0xFFFF are used as broadcast addresses.