ATIM ARM-N8-LD User manual

Advanced radio modems
Nano transceiver modules
N8-LD/LP
User Guide
Concerned models:
ARM-N8-LD (Long distance)
ARM-N8-LP (Low power)
ARM-N8-SF (Sigfox)

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ATIM_ARM-N8-LD-LP_UG_EN_V2.0
TABLE OF CONTENTS
Document version history............................................................................................................................... 4
Disclaimer........................................................................................................................................................ 4
Trademarks and copyright .............................................................................................................................. 4
Declaration of compliance .............................................................................................................................. 5
Environmental recommendations .................................................................................................................. 5
Environment ........................................................................................................................................5
Radio.................................................................................................................................................... 6
Radio regulations ............................................................................................................................................ 7
i. Context....................................................................................................................................................... 7
ii. Information about the regulation and the conformity ..............................................................................7
Generalities..................................................................................................................................................... 9
i. Presentation...............................................................................................................................................9
ii. ARM range and ACW range........................................................................................................................ 9
iii. Soldering & Environment ........................................................................................................................... 9
Technical features......................................................................................................................................... 10
i. Electrical and mechanical characteristics................................................................................................. 10
ii. Dimensions............................................................................................................................................... 10
iii. Pins........................................................................................................................................................... 11
iv. Consumption features.............................................................................................................................. 11
v. Link interfaces .......................................................................................................................................... 12
vi. Firmware update...................................................................................................................................... 12
vii. RF features ............................................................................................................................................... 13
viii. Delay......................................................................................................................................................... 13
ix. Memory.................................................................................................................................................... 14
Hardware integration.................................................................................................................................... 15
i. Power supply............................................................................................................................................ 15
ii. Impedance of the antenna adaption........................................................................................................15
iii. Print and ground plan............................................................................................................................... 15
AT command configuration........................................................................................................................... 16
Test modes.................................................................................................................................................... 17
i. Ping-pong mode (ATT00 and ATT01)........................................................................................................17
ii. Continuous reception mode (ATT02) ....................................................................................................... 17
iii. Pure carrier (ATT04) ................................................................................................................................. 17
iv. RSSI reading (ATT0A) ................................................................................................................................ 17
v. Version ..................................................................................................................................................... 18
Interfaces ...................................................................................................................................................... 19
i. Selection................................................................................................................................................... 19
ii. UART mode............................................................................................................................................... 19

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ATIM_ARM-N8-LD-LP_UG_EN_V2.0
iii. UART Configuration (in yellow: by default).............................................................................................. 20
iv. Serial buffers ............................................................................................................................................ 21
v. Mode SPI .................................................................................................................................................. 22
Operating mode............................................................................................................................................ 26
i. Transparent (serial/RF bridge: ARM-N8-LP/LD) ....................................................................................... 26
ii. Sigfox Uplink (ARM-N8-SF)....................................................................................................................... 32
Radio part...................................................................................................................................................... 34
i. Principal parameters (by default)............................................................................................................. 34
ii. Header...................................................................................................................................................... 34
iii. Radio channels ......................................................................................................................................... 36
iv. Whitening................................................................................................................................................. 36
v. Listen before talk (LBT)............................................................................................................................. 37
vi. Adaptive Frequency Agility (AFA)............................................................................................................. 38
vii. Repeater................................................................................................................................................... 38
Sleep mode ................................................................................................................................................... 39
i. Sleep/wake-up sources ............................................................................................................................ 39
ii. Entrance and exit of the sleep mode condition ....................................................................................... 39
Wake On Radio (WOR).................................................................................................................................. 41
i. Principal.................................................................................................................................................... 41
ii. WOR reception method ........................................................................................................................... 42
iii. Post-WOR treatment................................................................................................................................ 42
iv. Wake up events (example)....................................................................................................................... 43
Signalizations................................................................................................................................................. 45
Measured current at 3,3V............................................................................................................................. 46
Consumed current Optimization................................................................................................................... 47
Firmware update by bootloader................................................................................................................... 48
i. Versions.................................................................................................................................................... 48
ii. Using the Upgrader.exe............................................................................................................................ 48
Frequency table ............................................................................................................................................ 49
AT registers table .......................................................................................................................................... 61

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ATIM_ARM-N8-LD-LP_UG_EN_V2.0
Document version history
Disclaimer
The information contained in this document is subject to change without warning and does not represent a
commitment on the part of ATIM radiocommunications. ATIM radiocommunications provides this document ‘as-is’
with no warranty of any kind, express or implied, including but not limited to implied warranties of merchantability
or fitness for a particular purpose. ATIM radiocommunications may make changes and/or improvements to this
manual or to the product(s) or program(s) described in this manual, at any time.
Trademarks and copyright
ATIM radiocommunications®, ACW ATIM Cloud Wireless® and ARM Advanced Radio Modem® are registered
trademarks of ATIM SARL in France. The other trademarks mentioned in this document are the property of their
respective owners.
Version
Date
Description
Author
1.0
17/05/2014
Creation
TD
1.4
13/05/2014
WOR mode, new frequencies table,
Declaration of conformity, SPI mode, Repeater mode, Signalizations
TD
1.5
25/11/2015
Sigfox Uplink
TD
1.6
02/12/2015
Document title, post-WOR
TD
1.7
07/12/2015
UART parity correction
TD
1.8
25/11/2015
RSSI-PWM unavailable on Sigfox modems
TD
1.9
30/03/2016
Various corrections (Radio and consumption)
TD
2.0
02/06/2020
Document format and translation
MD

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ATIM_ARM-N8-LD-LP_UG_EN_V2.0
Declaration of compliance
All ARM Advanced Radio Modems® products comply with the regulatory requirements of the R&TTE Directive
(1999/5/EC), article 3:
1 SAFETY (Article 3.1a of the 1999/5/EC Directive)
EN62311:2008 Human Exposure Restrictions for Electromagnetic Fields
EN61000-6-2: 2005 Electromagnetic compatibility (EMC) - Immunity for industrial environments
2 Electromagnetic compatibility (Article 3.1b of the 1999/5/EC Directive)
EN 301489-3 v1.4.1, EN 301489-1 V1.9.2
3 Efficient use of the radio frequency spectrum (Art.3.2 of the 1999/5/EC Directive)
ETSI EN300 220-2 v2.4.1 and EN300 220-1 v2.4.1
Receiver class: 2
It is under the responsibility of the user to unsure that the configuration and the usage of the
ARM-N8-LDLP fills in all the conditions 70-03 of the REC (describing the annex 1, the radio bands, g, G1, G2, G3 or
G4).
Environmental recommendations
Environment
Respect the temperature ranges for storage and operation of all products. Failing to respect these guidelines could
disrupt device operation or damage the equipment.
Follow the instructions and warnings provided below to ensure your own safety and that of the environment and to
protect your device from any potential damage.

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ATIM_ARM-N8-LD-LP_UG_EN_V2.0
General hazard –Failure to follow the instructions presents a risk of equipment damage.
Electrical hazard –Failure to follow the instructions presents a risk of electrocution and physical injury.
Direct-current symbol
WARNING: do not install this equipment near any source of heat or any source of humidity.
WARNING: for your safety, it is essential that this equipment be switched off and disconnected from mains power
before carrying out any technical operation on it.
WARNING: the safe operation of this product is ensured only when it is operated in accordance with its intended
use. Maintenance may only be performed by qualified personnel.
Waste disposal by users in private households within the European Union. This symbol appears on a product or
its packaging to indicate that the product may not be discarded with another household waste. Rather, it is
your responsibility to dispose of this product by bringing it to a designated collection point for the recycling of
electrical and electronic devices. Collection and recycling waste separately at the time you dispose of it helps
to conserve natural resources and ensure a recycling process that respects human health and the environment.
For more information on the recycling centre closest to your home, contact your closest local government office,
your local waste management service or the business from which you purchased the product.
Radio
Modems in the ARM line are radio-communication modems that use the ISM (industrial, scientific,
and medical) bands, which may be used freely (at no cost and with no authorisation required) for industrial, scientific
and medical applications.

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ATIM_ARM-N8-LD-LP_UG_EN_V2.0
Radio regulations
i. Context
The modems from the ARM and ACW range are part of the radio communication that use the ISM (Industry Scientific
Medical) band that can be use freely (free and without authorization) for industrial, scientific, and medical
applications.
A regulation has been put in place at a national and worldwide standard to control interferences and saturation of
the radio bands. For the national, la regulation is insured by the ANFR (National frequencies Agency) and the ART
(Regulation Authority of Telecommunications). The ANFR was created in 1996, they elaborated and edited the
national distribution of the radio bands based on the radio regulation made as part of the UIT.
Concerning the civil applications, the conditions are fixed by the ART who decides the frequencies with a planning.
This planning is done by cutting in regions which is also cut in different bands. Then every radio communication
service is defined and a list of operators. A distinction by category is done, we can find the ministries (Defense,
Research, Interior), the ART and the CSA.
ii. Information about the regulation and the conformity
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 Union 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.
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.
Figure 1 : ISM bandwidths use around the world

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ATIM_ARM-N8-LD-LP_UG_EN_V2.0
Frequency Band
Power/Magnetic
Field
Spectrum access and
mitigation
requirements
Modulation/
maximum 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
modulation.
No channel spacing,
however, the whole
stated frequency 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 frequency 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
modulation
The whole stated
frequency band may be
used as 1 channel for
high speed data
transmission
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
modulation.
No channel spacing,
however, the whole
stated frequency band
may be used
Tableau 1: frequencies’bandwidths applicable to the 868 MHz bandwidth for
"Nonspecific to short range devices" specified in the ERC 70-03, [2].

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ATIM_ARM-N8-LD-LP_UG_EN_V2.0
Generalities
i. Presentation
In order to answer 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 Spread Spectrum (CSS). This family has been developed for users requiring high communication
range.
In fact, all the ARM-N8Lx devices have a range further than 22 km considering 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 is pin to pin compatible, allowing users to get different communication possibilities without having to
redesign their hardware.
ii. ARM range and ACW range
Since 2014, the ARM product range has been replaced by the ACW range. The ARM-Nano radio modules managed
the transition between the two ranges insuring the radio compatibility.
The AT commands of the old modules ARM-U8 or ARM-C8 are not compatible with the ARM-Nano (The AT
commands addresses stay compatible).
The Nano product range is available in N8: 868MHz:
▪N8-LP: Low Power module (P=14dBm)
▪N8-LD: Long distance module (P= 27dBm)
iii. Soldering & Environment
Before implementing of soldering the ARM-N8 module, it needs to be totally disconnected from the power
supply. It is forbidden to change components while the power supply is still connected.
This would damage the equipment. Keep away from any humidity, do not pour any liquid on the module. The
Arm radio module is supposed to be used inside and at an altitude less than 2000 meters.

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ATIM_ARM-N8-LD-LP_UG_EN_V2.0
Technical features
i. Electrical and mechanical characteristics
ii. Dimensions
For the ARM-Nx-LD or Nx-LP, the dimensions are similar.
Dimensions
30 x 18 x 2,5 mm (25 pins)
Radio Regulation
EN 300 220 V2.4.1
Operating Temp
-20°C to +70°C
Modulation
2GFSK/4GFSK
Sensitivity
-122dBm @1,2kbps BER10-3
Range
>20 km (FEL)
Frequency
863 –870 MHz
Output power max
500 mW (27 dBm)
Data rate
100 bit/s to 115,2 Kbit/s
Radio consumption (Tx)
500 mA (27dBm)
Sleep consumption
1µA (ARM N8LP), 2.5 µA (ARM N8LD)
Radio consumption (Rx)
26 mA
Interface (max)
UART (0,2MHz)/SPI (1,3MHz)
Setup
AT cmds / SPI cmds / Modbus registers
Features
LBT, AFA, FastUARTwakeUp, WakeOnRadio, Repeater
SMD Mounting
18mm
30mm