ATIM Lora ARM-N8-LW User manual

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ARM-N8-LW
UserGuide

ARM-N8-LW_UserGuide_V0.4
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Document Information
Revision History
Version
Notes
Firmware supported
V0.1
First preliminary release
Rev.15.1013.1414
V0.2
First release (2015/11/02 CB)
Rev.15.1030.1218
Rev.15.1123.1419
V0.2b
Preliminary removed (2016/01/11 TDX)
Rev.15.1124.1644
Rev.15.1124.1700
Rev.16.0310.1622
Rev.16.0325.1202
V0.3
Second release (2016/04/07 CB)
LoRaWan 1.0 implementation (GIT v4.0.0)
Ready To Use implementation (RTU)
WakeUp on uart
OTAA
OTA command mode
Rev.16.0309.1008
V0.4
Add functionality (2016/04/29 CB, correction TDX)
LoRaWan 1.0 implementation (GIT v4.1.0)
Add periodic emission: ATT0E
Rev.16.0407.1130
File name
ARM-N8_LW UserGuide V0.4
Created
2015-10-29
Total pages
Total pages 35

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CONTENTS
I. GENERALITIES ......................................................................................................................................... 6
A. PRESENTATION.............................................................................................................................................. 6
B. GENERAL INFORMATIONS ................................................................................................................................ 6
C. REGULATION ASPECTS..................................................................................................................................... 6
1. Radio frequency ................................................................................................................................... 6
2. Information about the conformity regulation...................................................................................... 7
D. LORAWAN ................................................................................................................................................... 8
1. Generalities .......................................................................................................................................... 8
2. Modulation......................................................................................................................................... 10
3. Communication.................................................................................................................................. 11
II. TECHNICAL CARACTERISTICS ................................................................................................................. 12
A. DIMENSIONS............................................................................................................................................... 12
B. PINOUT...................................................................................................................................................... 12
C. ELECTRICAL FEATURES................................................................................................................................... 13
D. COMMUNICATION INTERFACE......................................................................................................................... 13
E. FUNCTIONING MODE .................................................................................................................................... 14
F. FIRMWARE UPDATE...................................................................................................................................... 14
G. RADIOFREQUENCY CARACTERISTICS ................................................................................................................. 14
H. DELAYS ...................................................................................................................................................... 15
I. MEMORY ................................................................................................................................................... 15
1. Memories ........................................................................................................................................... 15
2. Data ................................................................................................................................................... 16
3. Organization ...................................................................................................................................... 16
4. How does it work?.............................................................................................................................. 16
III. HARDWARE INTEGRATION .................................................................................................................... 18
A. ALIMENTATION ........................................................................................................................................... 18
B. IMPEDANCE ADAPTATION FOR ANTENNA PATH................................................................................................... 18
C. MODULE FOOTPRINT AND GROUND-PLAN......................................................................................................... 18
IV. DEVICE FUNCTIONNEMENT ................................................................................................................... 20
A. ORGANISATION ........................................................................................................................................... 20
B. BUFFER INFORMATION.................................................................................................................................. 20
C. NORMAL FUNCTIONING MODE ....................................................................................................................... 21
1. Transparent UART/RF BRIDGE ........................................................................................................... 21
2. Ready To Use (RTU)............................................................................................................................ 21
D. COMMAND MODE........................................................................................................................................ 21
1. Local ................................................................................................................................................... 21
2. Distant................................................................................................................................................ 21
3. AT COMMAND ................................................................................................................................... 22
E. TEST MODE ............................................................................................................................................. 23
1. Battery level (ATT08).......................................................................................................................... 23
2. RSSI reader (ATT09)............................................................................................................................ 23
3. Continuous RSSI reader (ATT0A) ........................................................................................................ 23
4. Periodic emission (ATT0E) .................................................................................................................. 24

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V. TUNING ................................................................................................................................................. 25
A. MODULE.................................................................................................................................................... 25
1. Module configuration ........................................................................................................................ 26
2. Functionality ...................................................................................................................................... 26
3. Led behaviour..................................................................................................................................... 28
B. UART ....................................................................................................................................................... 28
1. Parameters......................................................................................................................................... 28
C. RADIO ....................................................................................................................................................... 29
1. Main parameters ............................................................................................................................... 29
2. LoRaWan parameters (Read only) ..................................................................................................... 32
3. IDs ...................................................................................................................................................... 33
VI. INFORMATION ...................................................................................................................................... 34
A. MATERIAL INFORMATION....................................................................................................................... 34
1. RECOMMENDED SOLDERING REFLOW PROFILE ................................................................................ 34
B. ENVIRONMENTAL INFORMATION........................................................................................................... 34
C. MOISTURE SENSITIVITY........................................................................................................................... 35
TABLE LIST
Table 1: Power distribution in 868 band................................................................................................. 7
Table 2: Pinout ...................................................................................................................................... 12
Table 3: Electrical ratings ...................................................................................................................... 13
Table 4: Timing table ............................................................................................................................. 15
Table 5: Global memory organization ................................................................................................... 16
Table 6: AT command list ...................................................................................................................... 22
Table 7: Test mode list .......................................................................................................................... 23
Table 8: Device configuration, AT commands....................................................................................... 25
Table 9: Low Power mode summary..................................................................................................... 27
Table 10: Uart configuration, AT commands ........................................................................................ 28
Table 11: Main radio configuration, AT commands .............................................................................. 30
Table 12: LoRaWan parameters (read only).......................................................................................... 32
Table 13: IDs access, AT commands...................................................................................................... 33
FIGURE LIST
Figure 1: LoRa Logo ................................................................................................................................. 8
Figure 2 : Stars of Stars topology............................................................................................................. 9
Figure 3: Class A endpoint radio scheme ................................................................................................ 9
Figure 4 : Class C endpoint radio scheme.............................................................................................. 10
Figure 5 : Modulation Up-Chirp............................................................................................................. 10

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Figure 6 : Gabarit d'une émission en modulation LoRa ........................................................................ 11
Figure 7: Module dimensions................................................................................................................ 12
Figure 8: Module footprint.................................................................................................................... 12
Figure 9: Memory access and organization........................................................................................... 17
Figure 10 : Alimentation filter ............................................................................................................... 18
Figure 11: Impedance adaptation ......................................................................................................... 18
Figure 12: Module footprint and ground plan ...................................................................................... 19
Figure 13: Device configuration ............................................................................................................ 25
Figure 14: Timing for Low Power On, programmed to wake up on wake up pin ................................. 27
Figure 15: Timing for Low Power On, programmed to wake up on Uart Rx pin................................... 28
Figure 16: Reflow profile ....................................................................................................................... 34

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I. GENERALITIES
A. PRESENTATION
In order to answer the more accurately to various user challenges, ATIM started a new device family called
Nano-Modules composed of different modules using state of the art technologies like Ultra Narrow Band
(UNB), Narrow Band (NB) and Chirp Spred Spectrum (CSS). This family has been developed for users re-
quiring high communication range.
In fact, all the ARM-N8Lx devices have a range further than 22 km in light of sight, the ARM-N8LORA exceeds
25 km and the ARM-N1LD (169Mhz) goes over 40 km. Some modules can also benefit an extended range
with the repeater functionality.
ARM-N8LP/LD have double functionality, they can be used in local mode (P2P) (ISM network) and/or in
SIGFOX networks (SIGFOX™ network). ARM-N8LORA can also be used in two mode, point to point LoRa
communication or FSK local mode (P2P).
Every module is optimized to get the lowest power consumption possible, allowing users to develop battery
powered devices. With the right batteries and configuration, a module can be used up to 10 years without
changing batteries.
Every module are pin to pin compatible, allowing users to get different communication possibilities without
having to redesign their hardware.
B. GENERAL INFORMATIONS
General information :
Frequency: 863-870MHz
RF data rate: 100 to 5700 bps
Modulation: CSS
Output power: 2 to 14 dBm
Sensitivity: -142 dBm
Link budget: 161dB
Range up to: 25km
Interface: UART
Dimensions: 30mm x 18mm
Certified: EN 300 220 V2.4.1
Operating temperature: -20°C /+70°C
LBT AFA
Typical application:
Internet Of Things (IoT)
Environment,
Intelligent structures,
Telemetry,
Alarm and wireless security systems,
M2M,
Remote sensors,
Remote control
C. REGULATION ASPECTS
1. Radio frequency
The Table 1 shows sub-band frequencies in the 868 MHz band for “short range non specifics devices” spec-
ified in the recommendation ERC 70-03, [2].

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Table 1: Power distribution in 868 band
Frequency Band
Power/Mag-
netic Field
Spectrum access
and mitigation re-
quirements
Modulation/ maxi-
mum occupied
bandwidth
ECC/ERC
Decision
Notes
g1
863-870 MHz
(notes 3 and 4)
25 mW e.r.p.
≤ 0.1% duty cycle or
LBT
(notes 1 and 5)
≤ 100 kHz for 47 or
more channels
(note 2)
FHSS
25 mW e.r.p.
Power density:
-4.5 dBm/100kHz
(note 7)
≤ 0.1% duty cycle or
LBT+AFA
(notes 1, 5 and 6)
No spacing
DSSS and other wideband
techniques other than FHSS
25 mW e.r.p.
≤ 0.1% duty cycle or
LBT+AFA
(notes 1 and 5)
≤ 100 kHz, for 1 or
more channels
modulation bandwidth
≤ 300 kHz
(note 2)
Narrow /wide-band
modulation
g1.1
868-868.6 MHz
(note 4)
25 mW e.r.p.
≤ 1% duty cycle or
LBT+AFA
(note 1)
No spacing, for 1 or
more channels
(note 2)
Narrow / wide-band modula-
tion
No channel spacing,
however the whole stated fre-
quency band may be used
g1.2
868.7-869.2
MHz
(note 4)
25 mW e.r.p.
≤ 0.1% duty cycle or
LBT+AFA
(note 1)
No spacing, for 1 or
more channels
(note 2)
Narrow / wide-band
modulation
No channel spacing,
however the whole stated fre-
quency band may be used
g1.3
869.4-869.65
MHz
500 mW e.r.p.
≤ 10% duty cycle or
LBT+AFA
(note 1)
No spacing, for 1 or
more channels
Narrow / wide-band modula-
tion
The whole stated frequency
band may be used as 1 chan-
nel for high speed data trans-
mission
g1.4
869.7-870 MHz
(note 11)
5 mW e.r.p.
25 mW e.r.p.
No requirement
≤1% duty cycle or
LBT+AFA
(note 1)
No spacing for 1 or
more channels
Narrow / wide-band modula-
tion
No channel spacing,
however the whole stated fre-
quency band may be used
2. Information about the conformity regulation
Utilization of radio frequencies is limited by national regulations. Radio modules are conceived to follow
the R&TTE (Radio & Telecommunications Terminal Equipment) directive 1999/5 / CE from European Un-
ion, and can be freely used in European Union. Nevertheless, restrictions regarding RF power or duty cycle
can be applied.
The ARM-N8-LD/LP is a radio module conceived to be integrated in another product, often final products.
According to the R&TTE directive, the final product producer is responsible of the conformity declaration
for this product. The ARM-N8xx module conformity declaration is available on demand at ATIM, however,
it does not cover the product where it is integrated in.
Regulation requirements can change, ATIM does not take responsibility of the exactitude and precision
aforementioned.
Legislation and national regulations, just as their interpretation can vary accordingly to the country. In case
of uncertainty, it is recommended to contact ATIM or to consult local authorities in the concerned country.

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D. LORAWAN
LoRa™ is a high range, low power consumption and low datarate wireless modulation developed by Sem-
tech and supported by LoRa Alliance. LoRaWan stack is mainly developed for battery powered devices, ei-
ther fixed or mobile. It is optimized for the Internet Of Things (IOT).
Figure 1: LoRa Logo
1. Generalities
Just for the record, LoRaWan protocol is still young and evolve quickly. There is constantly modifications
and adaptations to realize in order to follow these evolutions. Furthermore, with the quick start and devel-
opment of the LoRa Alliance, LoRaWan protocol changed its name from LoRaMac to LoRaWan. This change
is not yet effective everywhere, it is possible to found documents with term LoRaMac or Mac.
LoRaWan network is typically in a Star to Star topology, see Figure 2. Gateways
1
pass messages between
end devices and central server network (often on the internet). Gateways are connected to the network
with a standard IP connection, whereas endpoints uses single hoping communication to join one or more
gateways. Every communication are usually bidirectional, even if uplinks
2
are more frequently used than
downlinks
3
.
Figure 2 shows Stars to Stars topology, in this example, network extremities are end devices, and those are
linked to gateways to relay information to a central server network on the Internet.
1
Gateway: also know under the name of concentrator or base station.
2
Uplink: communication from end device to the Internet.
3
Downlink: communication from the Internet to an end device.

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Gateway
Device
Device
Device
Gateway
Device
Device
Device
Internet of
things
Gateway
Device
Device
Device
Gateway
Device
Device
Device
Figure 2 : Stars of Stars topology
Communication between the endpoint and concentrator is possible on different frequency channels and
uses different spreading factors. The channel is chosen randomly between those available, command sent
by concentrator can add new channels if needed. The choice of a spreading factor is a compromise between
communication range and data rate, lower data rate will achieve higher communication range. The data rate
goes from 0,3 Kb/s to 50 Kb/s. To optimize battery lifetime and network overload, network infrastructure
automatically adapts spreading factor and emission power for each endpoint individually, following an
Adaptive Data Rate scheme (ADR).
LoRaWan protocol defines three device classes, A, B and C. This diversity allows an answer adapted to every
need. All devices implement at least functionalities of a class A device.
• Bidirectional endpoint (Class A):
Class A endpoint allows bidirectional communication with the applicative layer by opening two receive win-
dows (Rx1 and Rx2) after each emission, see Figure 3.
Receive windows allows the endpoint to receive downlink communication.
Figure 3: Class A endpoint radio scheme
• Bidirectional endpoint with programed receive windows (Class B):

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Class B endpoint follows Class A behaviour with the functionality to open receive windows at a precise time.
This windows are based on temporal information given by the network structure.
• Bidirectional endpoint with continuous reception (Class C):
Class C endpoint follows Class A behaviour on top of continuous listening on a channel. It allows endpoint
with continuous power supply to be in a continuous reception when it is not emitting an uplink, see Figure
4.
Figure 4 : Class C endpoint radio scheme
2. Modulation
LoRa modulation is based on CSS
4
type. It uses Chirp
5
on a wide band to communicate.
Like other wide spectrum modulation, CSS use all the band allocated. It make the communication more re-
sistant to channel noises, and to multipath fading, even for low power emission.
An Up-Chirp example is available on Figure 5. Figure 6 shows typical emission pattern for a LoRa modula-
tion.
Figure 5 : Modulation Up-Chirp
4
CSS: Chirp Spread Spectrum.
5
Chirp: signal where frequency increased or decreased with time, also called Up-Chirp et Down-Chirp.